Bacteriophage Ecology Group
Reference Abstracts (1985)
Dedicated to the ecology and evolutionary biology of the parasites of unicellular organisms (UOPs)
© Stephen T. Abedon
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© Phage et al. last updated on Wednesday, December 26, 2001
  1. THE N SYSTEM OF BACTERIAL CONJUGATION: GENETIC ANALYSIS AND RELATIONSHIP TO PHAGE SENSITIVITY AND THE KILLING OF KLEBSIELLA PNEUMONIAE. ??? (1985). CARLETON UNIVERSITY (CANADA). Conjugative antibiotic resistance plasmids of the incompatibility group N (IncN) have a wide host range and confer upon their bacterial hosts sensitivity to the bacteriophages IKe and PRDl and the ability to kill Klebsiella pneumoniae when conjugated with the latter. In this study, the regions on a particular IncN group plasmid pCUl that determine these plasmid-associated phenotypes have been analysed using a variety of molecular genetic techniques and concepts--restriction endonuclease mapping, deletion mapping, transposon mutagenesis, molecular cloning and genetic complementation. A continuous 19.4 Kb region when cloned into the small non-transmissible plasmid pACYC184 conferred self-transmissibility and phage sensitivity to the strain carrying it. This tra region was cloned by introducing HindIII sites artificially into regions of the plasmid where such sites do not normally exist. A large number of Tn5 insertions were isolated and mapped to regions of the plasmid both at the ends of this 19.4 Kb tra region as well as within it. The phenotype affected by these transposon insertions and of subclones and deletions derived from plasmids carrying them, reduced the tra region to 16 Kb. A subset of this region (11.2 Kb) at one end of tra determined IKe and PRDl sensitivity. Insertions at the other end abolished the Tra phenotype but not phage sensitivity. This 5.4 Kb region was inferred to be concerned with some other aspect of conjugation. The region required in cis for plasmid transfer (mob region) was localized to a 1.2 Kb sequence at the end of tra away from the pilus region. A large number of Tn5 derivatives of pCUl and of a tra-containing clone were used for a genetic complementation analysis of the tra region. Using two different genetic complementation tests, it was concluded that there are at least eight complementation units within tra, six of which were localized to the pilus region. This is the minimum number of tra complementation units since there were two regions (1.3 Kb and 2 Kb in size) within the 16 Kb tra region where none of the 117 insertions that were used, mapped. The plasmid carrying the cloned 19.4 Kb tra region did not mediate killing of K. pneumoniae. For this killing to occur an additional 3 Kb region beyond tra at the mob end needed to be cloned. On the basis of this observation and the isolation of Tn5 insertions at the opposite end of tra which led to a Kil('-) but Tra('+) phenotype, it was concluded that two separate regions flanking tra were both needed for this phenotype. [TOP OF PAGE]

  2. New actinophage species. Ackermann, H.-W., Berthiaume, L., Jones, L.A. (1985). Intervirology 23:121-??? [TOP OF PAGE]

  3. Aeromonas bacteriophages: Reexamination and classification. Ackermann, H.-W., Dauguet, C., Paterson, W.D., Popoff, M., Rouf, M.A., Vieu, J.-F. (1985). Ann. Inst. Pasteur Virol. 136E:175-??? [TOP OF PAGE]

  4. Les virus des bactéries. Ackermann, H.-W. (1985). p. 196-??? In Maurin, J. (ed.), Virologie Médicale. Flammarion Médecine-Sciences, Paris. [TOP OF PAGE]

  5. NEW BACTERIOPHAGES OF STAPHYLOCOCCUS-EPIDERMIDIS AND THEIR EPIDEMIOLOGICAL EVALUATION. Bes, M., BRUN, Y., FLEURETTE, J. (1985). Annales de Microbiologie (Paris) 135B:165-176. New bacteriophages of Staphylococcus epidermidis and their epidemiological evaluation.Fifty strains of S. epidermidis isolated from human infections were induced with mitomycin C; 8 phages (41, 63, 118-II, 138, 245, 336, 392 and 550) were isolated. These phages were propagated on 5 different strains of S. epidermidis. Their lytic activity was studied on 561 strains. Phages 336, 392 and 550 had a different host-range and different propagative strains; they typed 93% of the strains susceptible to the 8 phages. The other phages had an activity similar to that of phage 336. Of non-epidemic strains, 21% were susceptible to at least 1 of the 3 phages. The reproducibility, specificity and discriminatory power of these phages suggest they may be a useful addition to previously recognized phages. [TOP OF PAGE]

  6. STAPHYLOCOCCAL ENTEROTOXIN A IS ENCODED BY PHAGE. BETLEY, M.J., Mekalanos, J.J. (1985). Science (Washington D C) 229:185-187. Staphylococcal enterotoxin A is encoded by phage.The gene for staphylococcal enterotoxin A (entA), in 2 wild-type strains, is carried by related temperature bacteriophages. Hybridization analysis of DNA from entA-converting phage PS42-D and its bacterial host suggests that this phage integrates into the bacterial chromosome by circularization and reciprocal crossover (The Campbell model) and that the entA gene is located near the phage attachment site. DNA from 3 of 8 staphylococcal strain that did not produce enterotoxin A and 7 wild-type enterotoxin A-producing (EntA+) strains had extensive homology to the entA-converting phage PS42-D DNA, although there was a high degree of restriction-fragment length polymorphisms. At least 1 EntA+ strain did not produce detectable viable phage after induction. A polymorphic family of Staphylococcus aureus phages (some of which may be defective) can apparently carry the entA gene. [TOP OF PAGE]

  7. Mutation to resistance for virus AS-1 in the cyanobacterium Anacystis nidulans. Bisen, P.S., Audholia, S., Bhatnagar, A.K. (1985). Microbiol. Lett. 29:7-13. [TOP OF PAGE]

  8. DIFFERENCES IN THE PRODUCTION OF TEMPERATE BACTERIOPHAGES IN LYSOGENIC STRAINS OF SALMONELLA-ENTERITIDIS AND CITROBACTER. BORECKA, J., KAROLCEK, J. (1985). Ceskoslovenska Epidemiologie Mikrobiologie Imunologie 34:159-162. Differences in the production of temperate bacteriophages in lysogenic strains of Salmonella enteritidis and Citrobacter.Differences in the qualities of prophages in lysogenic strains of 2 bacterial species, pathogenic S. enteritidis and conditionally pathogenic Citrobacter were revealed. In lysogenic strains of S. enteritidis phage DNA was replicated. This was shown by the presence of mature phages in the medium. Under the same experimental conditions, it was not possible to isolate temperate phages in lysogenic strains of Citrobacter. The relationship of prophages of different qualities to microbial pathogeneity is discussed. [TOP OF PAGE]

  9. ISOLATION OF A BACTERIOPHAGE SPECIFIC FOR XANTHOMONAS-CAMPESTRIS PATHOVAR ARRACACIAE. BRITO, J.A.D., ROMEIRO, R.D.S., BROMMONSCHENKEL, S.H. (1985). Fitopatologia Brasileira 10:329 [TOP OF PAGE]

  10. ECOLOGY OF BACTERIOPHAGES IN A FRESH CHEESE FACTORY. BUDDE-NIEKIEL, A., MOELLER, V., Lembke, J., Teuber, M. (1985). Milchwissenschaft 40:477-481. Ecology of bacteriophages in a fresh cheese factory.69 Strains of Streptococcus cremoris isolated by chance from three mixed strain starter cultures of mesophilic lactic streptococci used in rotation in the examined dairy were characterized on the basis of their phage spectra. All the phages isolated in a period of 5 months from raw milk, bulk starter, whey and product samples and the phages isolated from the dairy air were found to belong to the morphological phage group P008. A remarkable characteristic of the isolated phages was their strict host specifity, attacking with few exceptions only strains of the starter culture used at the time of their isolation. The multiple strain culture A contained about 40% lyogenic strains. The released intact temperate phages could be differentiated morphologically and serologically from the virulent phage type P008 which was the predominant virulent phage type in the examined dairy. No indicator strains were detected for the induced temperate phages. It could be demonstrated that phenomena of restriction and modification are common among mesophilic lactic acid streptococci from commercial mixed strain starter cultures. [TOP OF PAGE]

  11. Isolation of different bacteriophages using the LamB protein for adsorption on Escherichia coli K-12. Charbit, A., Hofnung, M. (1985). J. Virol. 53:667-671. [TOP OF PAGE]

  12. Occurrence and properties of bacteriophages of Leuconostoc oenos in Australian wines. Davis, C., Silveira, N.F.A., Fleet, G.H. (1985). Appl. Environ. Microbiol. 50:872-876. [TOP OF PAGE]

  13. Identification of an enveloped phage, myoplasma virus L172, that contains a 14-kilobase single-stranded DNA genome. Dybvyg, K., Nowak, J.A., Sladek, T.L., Maniloff, J. (1985). J. Virol. 53:384-??? [TOP OF PAGE]

  14. EFFECT OF AN ACTIVATED SLUDGE WASTEWATER TREATMENT PLANT ON AMBIENT AIR DENSITIES OF AEROSOLS CONTAINING BACTERIA AND VIRUSES. Fannin, K.F., VANA, S.C., JAKUBOWSKI, W. (1985). Appl. Environ. Microbiol. 49:1191-1196. Effect of an activated sludge wastewater treatment plant on ambient air densities of aerosols containing bacteria and viruses.Bacteria- and virus-containing aerosols were studied during the late summer and fall seasons in a midwestern suburb of the USA before and during the start-up and operation of an unenclosed activated sludge wastewater treatment plant. The study showed that the air in this suburban area contained low-level densities of indicator microorganisms. After the plant began operating, the densities of total aerobic bacteria-containing particles, standard plate count bacteria, total coliforms, fecal coliforms, fecal streptococci, and coliphages increased significantly in the air within the perimeter of the plant. Before plant operations, bacteria were detected from 5 genera, Klebsiella, Enterobacter, Serratia, Salmonella and Aeromonas. During plant operations, the number of genera identified increased to 11. In addition to those genera found before plant operations, Escherichia, Providencia, Citrobacter, Acinetobacter, Pasteurella and Proteus, were also identified. Enteric viruses were detected in low densities from the air emissions of this plant. Only standard plate count bacteria remained at significantly higher than base-line densities beyond 250 m downwind from the center of the aeration tanks. Fecal streptococci and coliphages appeared to be more stable in aerosols than the other indicator microorganisms studied. In general, the densities of microorganism-containing aerosols were higher at night than during the day. The techniques used in this study may be employed to establish microorganism-containing aerosol exposure during epidemiological investigations. [TOP OF PAGE]

  15. Properties of new marine bactericidal Microvibrios. Finance, C., Durand, M. (1985). Archives Roumaines de Pathologie Experimentales et de Microbiologie 44:99-108. [TOP OF PAGE]

  16. Coliphages as indicators of enteric viruses in activated sludge. Fundenburg, S.W., Sorber, C.A. (1985). Water Res. 19:547-555. [TOP OF PAGE]

  17. Gene K of bacteriophage phi X174 codes for a protein which affects the burst size of phage production. Gillam, S., Atkinson, T., Markham, A., Smith, M. (1985). J. Virol. 53:708-709. Site-directed mutagenesis has been used to produce a T----A change at nucleotide 70 of phi X174 genome. This generates an am codon, TAG, in the gene K reading frame without affecting the amino acid, leucine, encoded by the overlapping gene A. The gene K mutant produces small plaques on su- hosts. It has an identical latent period, but a more reduced burst size than that of the wild-type phi X174. The reduced burst size in the gene K mutant suggests that the gene K protein, although not essential, has a role in increasing infectivity by increasing the burst size three- to sixfold. [TOP OF PAGE]

  18. Development of a bacteriophage typing system for Campylobacter jejuni and Campylobacter coli. Grajewski, B.A., Kusek, J.W., Gelfand, H.M. (1985). Journal of Clinical Microbiology 22:13-18. A bacteriophage typing system for Campylobacter jejuni and Campylobacter coli was developed with phages isolated from poultry feces. Data for phage selection were generated from a set of isolates of C. jejuni and C. coli from humans in Illinois. Selection of 14 phages from the 47 phages available was assisted by determination of the Sneath-Jaccard similarity coefficients and subsequent unweighted pair-group arithmetic averaging cluster analysis. The typing set was reproducible and stable in the 255 isolates from Illinois. Of these isolates, 94.5% were typable, with 46% represented by the four most common phage patterns. In a set of 51 isolates from humans outside of Illinois, 88.1% of the C. jejuni isolates were typable. Phage typing for C. jejuni and C. coli has excellent epidemiologic potential and should serve as a useful adjunct or alternative to serotyping systems in current use. [TOP OF PAGE]

  19. Effect of environmental factors on ratios of coliphages to indicator bacteria. Hejkal, T.W. (1985). Ann.Meet.Am.Soc.Microbiol. 225. [TOP OF PAGE]

  20. Method of conferring bacteriophage resistance to bacteria. Hershberger, C.L., Rosteck, P.R. (1985). (4,530,904). U.S. [TOP OF PAGE]

  21. Host range of LPP cyanophages. Johnson, D.W., Potts, M. (1985). International Journal of Systematic Bacteriology [INT. J. SYST. BACTERIOL. ] 35:76-78. The authors determined the sensitivities of 33 strains and variants of cyanobacteria to infection by the cyanophage LPP-1 archaetype, five LPP-1 serotypes, six LPP-2 serotypes, and 8 new LPP isolates. The LPP-1 archaetype and LPP-1 serotypes have different host ranges on strains of LPP group B. [TOP OF PAGE]

  22. Bacteroides bacteriophages isolated from human feces. Kai, M., Watanabe, S., Furuse, K., Ozawa, A. (1985). Microbiology and Immunology 29:895-899. [TOP OF PAGE]

  23. Comparison of selective media for assay of coliphages in sewage effluent and lake water. Kennedy, J.E., Jr., Bitton, G., Oblinger, J.L. (1985). Appl. Environ. Microbiol. 49:33-36. Selective media, including EC medium, gram-negative broth, nutrient broth (with 0.05% sodium deoxycholate), and lactose broth (with 0.05% sodium deoxycholate), as well as nonselective nutrient and lactose broth, were compared for the enumeration of coliphages by the agar layer method from activated sludge or after chloroform treatment with Escherichia coli B, E. coli C, or a mixed host of both E. coli B and C. With the exception of gram-negative broth, direct assays of all samples with the selective media generally resulted in significantly higher (P< 0.05) recoveries of coliphages than did assays of chloroform-treated samples with nutrient broth medium regardless of the host used. In addition, chloroform pretreatment resulted in decreased recovery of coliphages with each selective medium in most analyses. The highest recoveries of coliphages from all samples with each host, except lake water with E. coli C, were obtained by direct assay on EC medium. The selectivity of the EC and gram-negative media resultsed in suppression of bacterial interference on direct assay plates compared to that observed in nutrient agar medium with chloroform-treated samples. The use of certain selective media for the direct assay of environmental materials for coliphage may enhance the recovery of coliphages and obviate bacterial decontamination procedures. [TOP OF PAGE]

  24. Inactivation of Norwalk virus in drinking water by chlorine. Keswick, B.H., Satterwhite, T.K., Johnson, P.C., DuPont, H.L., Secor, S.L., Bitsura, J.A., Gary, G.W., Hoff, J.C. (1985). Appl. Environ. Microbiol. 50:261-264. Norwalk virus in water was found to be more resistant to chlorine inactivation than poliovirus type 1 (LSc2Ab), human rotavirus (Wa), simian rotavirus (SA11), or f2 bacteriophage. A 3.75 mg/liter dose of chlorine was found to be effective against other viruses but failed to inactivate Norwalk virus. The Norwalk virus inoculum remained infectious for five of eight volunteers, despite the initial presence of free residual chlorine. Infectivity in volunteers was demonstrated by seroconversion to Norwalk virus. Fourteen of 16 subjects receiving untreated inoculum seroconverted to Norwalk virus. Illness was produced in four of the eight volunteers and in 11 of 16 control subjects. A similar Norwalk virus inoculum treated with a 10 mg/liter dose of chlorine produced illness in only one and failed to induce seroconversion in any of eight volunteers. Free chlorine (5 to 6 mg/liter) was measured in the reaction vessel after a 30-minute contact period. Norwalk virus appears to be very resistant to chlorine which may explain its importance in outbreaks of waterborne disease. [TOP OF PAGE]

  25. Conjugal transfer from Streptococcus lactis ME2 of plasmids encoding phage resistance, nisin resistance and lactose-fermenting ability: evidence for a high-frequency conjugative plasmid responsible for abortive infection of virulent bacteriophage. Klaenhammer, T.R., Sanozky, R.B. (1985). Journal of General Microbiology 131 ( Pt 6):1531-1541. Streptococcus lactis ME2 exhibits at least three mechanisms which confer resistance to virulent bacteriophage. These include plasmid-induced interference with phage adsorption, host-controlled restriction and modification activities, and a heat-sensitive mechanism which suppresses development of virulent phage. Conjugal mating experiments were done with S. lactis ME2 to determine if phage-defence mechanisms present in this strain could be mobilized, associated with plasmid DNA elements and phenotypically characterized in transconjugants. Agar-surface matings of S. lactis ME2 with S. lactis LM0230 demonstrated that lactose-fermenting ability (Lac+) was transferred in a conjugation-like process at frequencies of 10(-6) per donor cell and was associated with a 40 MDal plasmid designated pTR1040. Resistance to nisin (Nisr) was acquired or lost simultaneously with Lac+, indicating that pTR1040 carried determinants for both phenotypes. Lac+ Nisr transconjugants that carried a 30 MDal plasmid (pTR2030) exhibited a heat-sensitive phage-defence mechanism (Hsp+) which limited the burst size and plaque size of phage c2 without altering the efficiency of plaquing (e.o.p.) or the level of adsorption. The ability of phage c2 to initiate plaquing at an e.o.p. of 1.0 indicated that DNA injection and early viral gene expression are not affected in the Hsp+ transconjugants. We suggest, therefore, that the Hsp+ phenotype may result from plasmid-induced abortive infection of phage dependent on the presence of pTR2030. Hsp+ transconjugants carrying pTR2030 also promoted high-frequency conjugal transfer of Lac+ Nisr associated with pTR1040 (greater than 10(-1) per donor cell). It was concluded that Hsp+ and determinants for conjugal transfer ability (Tra+) are located on pTR2030. [TOP OF PAGE]

  26. [Demonstration of Escherichia coli phages in the seashore zone and the use of this index in microbiological monitoring]. Kovaleva, N.V., Valakh, N.N. (1985). MIKROBIOLOGICHESKII ZHURNAL 47:88-91. [TOP OF PAGE]

  27. [Isolation and analysis of Pseudomonas aeruginosa PAO mutants resistant to nonlysogenic bacteriophages]. Kulakov, L.A., Mazepa, V.N., Boronin, A.M. (1985). Genetika 21:39-45. Nonlysogenizing Pseudomonas aeruginosa PAO bacteriophages were studied. According to morphology of the plaques, they were distributed into three groups: phi k, phi m and phi mn. The mutants of P. aeruginosa PAO resistant to these bacteriophages were selected. On the basis of cris-cross resistance analysis of the mutants, a formal scheme of the receptor sites on the P. aeruginosa PAO bacterial cell surface is drawn. It is shown that bacteriophages phi k and phi m use different receptors for their adsorption. The receptors of phi m and phi mn phages are specifically interconnected. Thus, the receptor for phi k phages is connected with the receptor for phage phi 11. It appears that the receptor for bacteriophage E79 is identical to those of phi m phages. The phi m receptor is of a composite structure: it includes two different receptors used by phi mn phages. [TOP OF PAGE]

  28. Constraints on the coevolution of bacteria and virulent phage: A model, some experiments, and predictions for natural communities. Lenski, R.E., Levin, B.R. (1985). Am. Nat. 125:585-602. One view of the coevolution of parasites and their hosts is that of a gene-for-gene arms race between host defenses and parasite counterdefences. We have incorporated mutations into a model of the ecological interactions between bacteria and virulent phage to determine rates of mutation that would be consistent with this scenario. The model assumes an open habitat (e.g., a chemostat) in which virulent phage and sensitive bacteria can coexist. Equilibrium densities of bacteria and phage are inversely proportional to the efficiency with which phage irreversibly adsorb to their hosts. The absolute rate at which mutations appear is proportional to the product of habitat size, population density, rate of increase, and mutation rate. ¶ The bacterium Escherichia coli B readily evolved resistance to virulent phage T4 in our chemostat experiments. Approximately 100 h was required for the appearance, establishment, and attainment of a resourse-limited population of these T4-resistant mutants; this time period is close to that predicted from the model when the parameters of the model are estimated independently. No hostrange phage T4 mutants appeared, yet the phage persisted even after the resistant bacteria had become resource-limited. We hypothesized that the failure to observe corresponding phage mutants indicates mutational constraints on the coevolutionary potential of this phage. We also hypothesized that the persistence of the wild-type phage indicates the presence of a minority population of sensitive bacteria that persists because of selective constraints which produce a competitive disadvantage for resistant baceria under resource-limiting conditions. Both of these hypotheses were verified. Host-range T4 mutants occurred at a rate on the order of 10-12 or less, and could not be expected in the chemostats for several years. T4-sensitive and -resistant bacteria had very nearly the same exponential growth rates, but at steady state the latter had approximately a 50% disadvantage. ¶ We also examined the interactions of E. coli B and virulent phages T2, T5, and T7 for evidence of selective and mutational constraints on the bacteria and phage, respectively. Under the conditions of our experiments, T2-resistant and T7-resistant (but not T4-resistant) bacteria also had clear competitive disadvantages to sensitive bacteria udner resource-limiting conditions. We were able to isolate T2 and T7 (but not T5) host-range mutants. Even with T2 and T7, however, we could not select indefinitely for host-range mutants active against higher-order resistant bacteria. This general asymmetry in the coevolutionary potential of bacteria and phage occurs becuase mutations conferring resistance may arise by either the loss or alteration of gene function, while host-range mutations depend on specific alterations of gene function. ¶ These constraints preclude observing endless arms races between baceria and virulent phage. Instead, because of the asymmetry in coevolutionary potential of these hosts and parasites, we anticipated that natural communities of coliform bacteria and virulent coliphage are dominated by bacterial clones resistant to all co-occurring virulent phage. If virulent pahge to which the dominant clones are sensitive should appear, then bacteria will either rapidly evolve resistance or be replaced by existing clones resistant to the phage. Thus, the role of virulent phage in structuring communities of bacteria is seen as important in determining clonal composition but uninportant in determining bacterial densities. [TOP OF PAGE]

  29. Bacteria and phage: A model system for the study of the ecology and co-evolution of hosts and parasites. Levin, B.R., Lenski, R.E. (1985). pp. 227-242. In In Rollinson, D. and Anderson, R.M. (eds.), Ecology and Genetics of Host-Parasite Interactions. Academic Press, London. The results are reviewed of theoretical and experimental investigations of the population biology of bacteria and bacteriophage, emphasizing those apsects of general interest in the study of host-parasite ecology and evolution. ¶ 1) Existence conditions: the conditions are considered udner which phage can invade bacterial populations and will stably co-exist with these hosts. Particular emphasis is given to the effects of phage resistant bacterial clones on these communities, and hypotheses are presented to account for the observation that experimental populations of bacteria and virulent phage are more stable than anticipated from theory. ¶ 2) Co-evolution: The nature and effects of selection on the interacting populations of bacteria and phage are examined. Evidence is presented that the resulting co-evolution is a constrained process, rather than the indefinite gene-for-gene arms race previously postulated. ¶ 3) Latency: Temperate bacteriophage are analogous to the latent virusses of eukaryotes. We critically discuss three classes of hypotheses for the ecological conditions and selective pressures responsible for the evolution and maintenance of temperate (as opposed to virulent) modes of phage reproduction. ¶ 4) Immunity: Bacterial restriction-modification systems are similar to the immune systems of higher organisms. The hypothesis is considered that restriction-modification systems evolved nad are maintained for the defence against phage infection and we speculate on the effects of this type of immune system on the population dynamics of bacteria and phage. ¶ 5) Coda: This review is concluded with a brief consideration of the use of phage for the biological control of bacteria. [TOP OF PAGE]

  30. Identification of Bacillus anthracis by API tests. Logan, N.A., Carman, J.A., Melling, J., Berkeley, R.C. (1985). J. Med. Microbiol. 20:75-85. API and morphological tests were examined for their ability to distinguish between 37 Bacillus anthracis strains (virulent and avirulent) and 194 strains of closely related Bacillus species (B. cereus, B. mycoides and B. thuringiensis). In addition, 34 strains of B. anthracis and four of B. cereus were tested by several other methods that included capsule formation, ability to grow on a selective medium, and sensitivity to phage. It was found that virulent strains of B. anthracis were easily separated from the closely related Bacillus species by most of the test methods; but separation of slightly virulent and avirulent strains of B. anthracis from the closely related species could be done only by API and phage-sensitivity tests. [TOP OF PAGE]

  31. Two bacteriophages of Clostridium difficile. Mahony, D.E., Bell, P.D., Easterbrook, K.B. (1985). Journal of Clinical Microbiology 21:251-254. Two temperate bacteriophages of differing morphology and host range were isolated by screening 94 isolates of Clostridium difficile. Phage 41 had a 300-nm flexible tail, whereas phage 56 had a shorter tail with a contractile sheath. Electron microscopy of phage 56 lysates exposed to elevated magnesium concentrations showed small virus-like particles which were 21 nm in diameter. The addition of MgCl2 to semisolid agar overlays enhanced both the titer and plaque size of phage 56. Phage 56 was more temperature labile than phage 41 and demonstrated unusual lability in buffer at pH 7.0. One-step growth and adsorption experiments revealed that both phages had latent periods of about 60 min, but phage 56 adsorbed to its indicator strain more efficiently. Phage 56, which was obtained from a toxigenic strain of C. difficile, was used to lysogenize its nontoxigenic indicator strain, but no conversion to toxigenicity was observed in this strain. [TOP OF PAGE]

  32. Regulation of populations with non-overlapping generations by microparasites: A purely chaotic system. May, R.M. (1985). Am. Nat. 125:573-584. [TOP OF PAGE]

  33. ISOLATION OF AVIRULENT MUTANTS OF ERWINIA-STEWARTII USING BACTERIOPHAGE MU-PF-7701. MCCAMMON, S.L., COPLIN, D.L., ROWAN, R.G. (1985). Journal of General Microbiology 131:2993-3000. Isolation of avirulent mutants of Erwinia stewartii using bacteriophage Mu pf7701.Bacteriophage Mu pf7701, a KmR derivative of Mu cts62, was inserted into the conjugative Erwinia stewartii plasmid pDC251, which carried Tn10. When pDC251::Mu pf7701 plasmids were conjugated from Escherichia coli into derivatives of E. stewartii strain SS104 they were unstable; loss of either or both drug resistance markers occurred. Stable transconjugants resulted from deletion of Mu sequences, integration of the plasmid into the chromosome, or loss of an indigenous 34 kb cryptic plasmid. Among transconjugatants selected for KmR, the largest colonies arose from transconjugants in which Mu pf7701 had transposed to the chromosome and the pDC251::Mu pf7701 plasmid had been lost; 1300 transconjugants of this type were screened for pathogenicity to corn (Zea mays) seedlings and eight mutants were obtained that did not cause watersoaking symptoms. The insertions of Mu pf7701 in these mutants were in the chromosome. [TOP OF PAGE]

  34. Chlorella viruses. Meints, R.H., Schuster, A.M., Van Etten, J.L. (1985). Plant Mol. Biol. Rep. 3:180-187. [TOP OF PAGE]

  35. CHARACTERIZATION OF A SHIGA-LIKE TOXIN CONVERTING PHAGE ISOLATED FROM AN ESCHERICHIA COLI STRAIN RESPONSIBLE FOR HEMORRHAGIC COLITIS IN HUMANS. Miller, S.F. (1985). Uniformed Services University of the Health Sciences. There is a strong correlation between the ability of Escherichia coli to produce high levels of Shiga-like toxin in vitro and to cause hemorrhagic colitis in humans. A Shiga-like toxin-converting phage from Escherichia coli 0157:H7 strain 933 (phage 933J) and another Shiga-like toxin-converting phage from Escherichia coli 026 strain H-19 (phage H-19J) were isolated and found to be closely related by morphology, virion polypeptide composition, pattern of DNA restriction fragments, heat stability, and lysogenic immunity. However, a difference was noted between phage 933J and H-19J in the range of bacterial hosts on which these phages would plaque. The phage 933J toxin-converting genes were cloned into pBR328 and expressed in Escherichia coli HB101. DNA restriction mapping, subcloning, and examination of the cloned gene products by minicell analysis were used to localize the toxin-converting genes and identify them as the structural genes for Shiga-like toxin. Southern hybridization studies demonstrated that the DNA fragment containing the cloned toxin structural genes was homologous with the chromosome of Shigella. [TOP OF PAGE]

  36. The nature of ompA mutants of Escherichia coli K12 exhibiting temperature-sensitive bacteriophage resistance. Morona, R., Kramer, C., Henning, U. (1985). Molecular & General Genetics 201:357-359. A class of ompA mutants of Escherichia coli, exhibiting temperature-sensitive resistance towards phages using the OmpA protein as receptor, was analysed. The mutants produce detectable levels of the protein at 42 degrees C but not at 30 degrees C (Manning and Reeves 1976). They were found to have a deletion (one isolate) or insertions (three isolates) upstream of the coding part of the ompA gene. Several previously characterized mutants possessing insertions or a deletion in the non-translated 5' area of the gene also exhibited a similar temperature-sensitive phage resistance. This cold-sensitive phenotype is explained in terms of the recent discovery that the stability of ompA mRNA is regulated by the rate of cell growth (Nilsson et al. 1984). [TOP OF PAGE]

  37. Comparative biology of intracellular parasitism. Moulder, J.W. (1985). Microbiol. Rev. 49:298-337. [TOP OF PAGE]

  38. A new biological activity in vitro of fat-soluble vitamins and related substances: phage-inactivating effect of vitamins E and K, and coenzyme Q. Murata, A., Imazu, K., Tokunaga, K. (1985). Agric. Biol. Chem. 49:1903-1904. [TOP OF PAGE]

  39. Sequential antigenic competition in teleosts: A bacteriophage-Aeromonas salmonicida interaction. O'Neill, J. (1985). pp. 141-156. In In Manning, M.J. and Tatner, M.F. (eds.), Fish Immunology. Passive immersion techniques have been used successfully in the bath immunisation of large numbers of fish, and have thus demonstrated that there is an interaction of water-borne antigens with the immunological mechanisms of fish. The present work was initiated to examine sequential antigenic competition in Salmo trutta and Cyprinus carpio challenged with the fish-furunculosis bacterium Aeromonas salmonicida . This bacterium was used as an example of a large and complex particulate immunogen which, as a formalin-killed organism or in the form of a natural infection, could be used to interact with the immune response to the bacteriophage MS2. [TOP OF PAGE]

  40. CHARACTERIZATION OF BACTERIOPHAGES VIRULENT TO FIELD ISOLATES OF RHIZOBIUM-TRIFOLII. Patel, J.J., CRAIG, A.S., CHANDRA, P. (1985). New Zealand Journal of Agricultural Research 28:283-288. Characterization of bacteriophages virulent to field isolates of Rhizobium trifolii.Bacteriophages parasitic to field strains of Rhizobium trifolii Dang were obtained from 9 separate soil samples from a ryegrass-clover pasture. The lytic patterns for these phages were determined for field strains and 3 standard inoculant strains of R. trifolii. The phages could be grouped into 3 categories: (1) those which lysed all field isolates as well as the standard inoculant strains; (2) those which lysed about half of the field isolates; and (3) those which caused only limited lytic responses. Only one phage (.vphi.WC2/1) fell into Category 1 and this phage had a distinctive large head, contractile tail morphology. The remaining 18 bacteriophages had small heads and non-contractile tails. [TOP OF PAGE]

  41. Phage plaques and autoplaques in Pseudomonas aeruginosa strains. Pillich, J., Kubickova, D., Vymola, F. (1985). Journal of Hygiene, Epidemiology, Microbiology and Immunology 29:163-167. Studies were made on the morphological variety in plaques produced by phage lysis and autoplaques in Pseudomonas aeruginosa strains. The great variability of phage plaque morphology may lead to a confusion with the autoplaques produced spontaneously by P. aeruginosa strains. The production of autoplaques is characteristic of a large number of clinical strains of P. aeruginosa. The appearance of autoplaques may complicate analysis of significant clinical strains of P. aeruginosa. [TOP OF PAGE]

  42. Characterization of streptococcal bacteriophage c6A. Powell, I.B., Davidson, B.E. (1985). J. Gen. Virol. 66 ( Pt 12):2737-2741. Bacteriophage c6A is a lytic phage that infects strains of Streptococcus lactis. Infection of S. lactis C6 under standard conditions yielded 124 +/- 8 p.f.u. per infected cell after a latent period of 25 min at 30 degrees C. The virion of c6A was shown to contain at least 12 polypeptides and a 21.9 kilobase double-stranded, linear DNA genome with complementary 5'-protruding single-stranded termini. The (G + C) content of this DNA was estimated to be 36.7%. A restriction map was constructed which indicates that a number of restriction endonucleases did not digest the DNA and that others cleaved with a much lower frequency than expected. [TOP OF PAGE]

  43. A note on a membrane filtration method for the concentration and enumeration of bacteriophages from water. Purdy, R.N., Dancer, B.N., Day, M.J., Stickler, D.J. (1985). J. Appl. Bacteriol. 58:231-233. [TOP OF PAGE]

  44. [Interaction of Yersinia pestis bacteria with bacteriophage mu]. [Russian]. Rakin, A.V., Lebedeva, S.A., Aleshkin, G.I. (1985). Molekuliarnaia Genetika, Mikrobiologia, i Virusologa 6-11. Yersinia pestis cells are shown to be sensitive to bacteriophage Mu cts62 infection. Lysis of bacteria has been shown to be more efficient on solid nutrient medium than in LB broth. 10(-5) pfu per ml is the maximal concentration of bacteriophage particles yielded from the broth cultures of bacteria. Moi 0.1 has been used to obtain such yields of bacteriophage. Lysogenization of Yersinia pestis cells has not been achieved when the standard methods of bacteriophage infection have been used. It was accomplished by the conjugal transfer of plasmid RP4::MU cts62 to Yersinia pestis from Escherichia coli. The deficiency of Yersinia pestis in producing bacteriophage Mu cts62 mature particles during the lytic cycle of bacteriophage is discussed. [TOP OF PAGE]

  45. LARGE-SCALE PRODUCTION OF PRUNIPHAGE FOR BIOCONTROL OF PRUNUS BACTERIAL SPOT DISEASE IN FIELD. RANDHAWA, P.S., Civerolo, E.L. (1985). Phytopathology 75:1328 [TOP OF PAGE]

  46. Virulent mutants of bacteriophage phi80. Reyes, O. (1985). Virology 146:50-68. We have characterized a collection of 11 phi80 mutants that develop in wild-type lysogenic hosts ("virulen"t phenotype). All these carry gross DNA rearrangements affecting the right arm of the phi80 chromosome. Our results are consistent with the notion that phi80 development is negatively controlled by the ineA gene product, encoded by one of a cluster of genes (phi80 immunity) located between the phi80 replication and recombination genes. We describe and assign positions for ineA and other genes within the immunity region. [TOP OF PAGE]

  47. Pasteurella haemolytica bacteriophage: identification, partial characterization, and relationship of temperate bacteriophages from isolates of Pasteurella haemolytica (biotype A, serotype 1). Richards, A.B., Renshaw, H.W., Sneed, L.W. (1985). American Journal of Veterinary Research 46:1215-1220. Pasteurella haemolytica (biotype A, serotype 1) isolates (n = 15) from the upper respiratory tract of clinically normal cattle, as well as from lung lesions from cases of fatal bovine pasteurellosis, were examined for the presence of bacteriophage after irradiation with UV light. Treatment of all P haemolytica isolates with UV irradiation resulted in lysis of bacteria due to the induction of vegetative development of bacteriophages. The extent of growth inhibition and bacterial lysis in irradiated cultures was UV dose-dependent. Bacterial cultures exposed to UV light for 20 s reached peak culture density between 60 and 70 minutes after irradiation; thereafter, culture density declined rapidly, so that by 120 minutes, it was approximately 60% of the original value. When examined ultrastructurally, lytic cultures from each isolate revealed bacteriophages with an overall length of approximately 200 nm and that appeared to have a head with icosahedral symmetry and a contractile tail. Cell-free filtrate from each noninduced bacterial isolate was inoculated onto the other bacterial isolates in a cross-culture sensitivity assay for the presence of phages lytic for the host bacterial isolates. Zones of lysis (plaques) did not develop when bacterial lawns grown from the different isolates were inoculated with filtrates from the heterologous isolates. [TOP OF PAGE]

  48. Presence of DNA, encoding parts of bacteriophage tail fiber genes, in the chromosome of Escherichia coli K-12. Riede, I., Eschbach, M.-L., Henning, U. (1985). J. Bacteriol. 163:832-836. [TOP OF PAGE]

  49. The receptor specificity of bacteriophage can be determined by a tail fiber modifying protein. Riede, I., Degen, M., Henning, U. (1985). EMBO J. 4:2343-2346. T-Even type bacteriophages recognize their cellular receptors with the distal ends of their long tail fibers. The distal part of these fibers consists of a dimer of gene product (gp) 37. The assembly of this gp to a functional dimer requires the action of two other proteins, gp57 and gp38. Genes (g) 38 have been cloned from five T-even type phages which use the Escherichia coli outer membrane protein OmpA as a receptor. The phages used differ in their ability to infect a series of ompA mutants producing altered OmpA proteins, i.e., each phage has a specific host range for these mutants. The cloned genes 38 complemented g38 amber mutants of phage T2, which uses the outer membrane protein OmpF as a receptor. The complemented phages had become phenotypically OmpA- dependent and, with one exception, OmpF-independent, but regained the host range of T2 upon growth in a host lacking the cloned g38. The host range of the complemented phages, as determined on the ompA mutants, was identical to, similar to, or different from that of the phage, from which the cloned g38 originated. The results presented show that gp38 from one phage can phenotypically 'imprint', in a finely-tuned manner, a host range onto gp37 of another phage with a different host specificity. In view of the extreme diversity of host ranges observed, it is suggested that gp38 of T2 and of the OmpA-specific phages may remain attached to gp37 in the phage particle and in cooperation with gp37 determine the host range. [TOP OF PAGE]

  50. The nucleotide sequences of the tail fiber gene 36 of bacteriophage T2 and of genes of the T-even type Escherichia coli phages K3 and Ox2. Riede, I., Drexler, K., Eschbach, M.-L. (1985). Nucl. Acids Res. 13:605-616. [TOP OF PAGE]

  51. ISOLATION AND CHARACTERIZATION OF TWO PHAGES FOR GLUCONOBACTER-OXYDANS. ROBAKIS, N.K., Palleroni, N.J., DESPREAUX, C.W., BOUBLIK, M., BAKER, C.A., CHURN, P.J., CLAUS, G.W. (1985). Journal of General Microbiology 131:2467-2474. Isolation and characterization of two phages for Gluconobacter oxydans.Two bacteriophages, designated GW6210 and JW2040, were isolated from decaying apples using Gluconobacter oxydans ATCC 621 and G. oxydans VPI 204JW, respectively. Electron microscopy showed that phage GW6210 belonged to group A and phage JW2040 to group C of Bradley's morphological classification. Phage GW6210 was unusually large, with a head diameter of 170 nm. Both phages contained double stranded DNA. The G + C content of the DNA of phage GW6210 was 29.3 mol% (Tm), and the size of the genome was approximately 250-300 kb. The size of the DNA of phage JW2040 was found to be 37 kb and the G + C content was 56.5 mol% (Tm). The host ranges of both phages were determined using 54 Gluconobacter, 52 Acetobacter and three Pseudomonas strains. Only the Gluconbacter strains were host for these phages. [TOP OF PAGE]

  52. Inactivation of T1 and T7 by subrefrigeration temperatures. Schiffenbauer, M., Calderon, M. (1985). Ann.Meet.Am.Soc.Microbiol. 268. [TOP OF PAGE]

  53. Morphology and ultrastructure of bacteriophages. An electron microscopical study. Slopek, S., Krzywy, T. (1985). Arch. Immunol. Ther. Exp. (Warsz) 33:1-227. [TOP OF PAGE]

  54. Results of bacteriophage treatment of suppurative bacterial infections. IV. Evaluation of results obtained in 370 cases. Slopek, S., Kucharewicz-Krukowska, A., Weber-Dabrowska, B., Dabrowski, M. (1985). Arch. Immunol. Ther. Exp. 33:219-??? [TOP OF PAGE]

  55. Results of bacteriophage treatment of suppurative bacterial infections. VI. Analysis of treatment of suppurative staphylococcal infections. Slopek, S., Kucharewicz-Krukowska, A., Weber-Dabrowska, B., Dabrowski, M. (1985). Archivum Immunologii et Therapiae Experimentalis 33:261-273. Analysis of phage therapy results was carried out on 273 cases of spontaneous and postoperative septic staphylococcal infections. The treatment appeared effective in 254 (93.0%) cases. Detailed analysis of the results obtained in particular disease categories revealed that staphylococcal bacteriophages may be efficiently applied in the treatment of suppurative staphylococcal infections resistant to antibiotics. [TOP OF PAGE]

  56. Results of bacteriophage treatment of suppurative bacterial infections. V. Evaluation of the results obtained in children. Slopek, S., Kucharewicz-Krukowska, A., Weber-Dabrowska, B., Dabrowski, M. (1985). Archivum Immunologii et Therapiae Experimentalis 33:241-259. The results of phage therapy applied in 114 cases of suppurative bacterial infections in children were analyzed. Positive therapeutic results were obtained in 109 (95.6%) cases. The results confirmed great effectiveness of bacteriophages in the treatment of septic infections, spontaneous or postoperative, caused by pyogenic Staphylococci, Klebsiella, Escherichia, Proteus and Pseudomonas bacteria. [TOP OF PAGE]

  57. Streptococcus cremoris M12R transconjugants carrying the conjugal plasmid pTR2030 are insensitive to attack by lytic bacteriophages. Steenson, L.R., Klaenhammer, T.R. (1985). Appl. Environ. Microbiol. 50:851-858. Conjugal transfer of lactose-fermenting ability (Lac+), nisin resistance (Nisr), and phage resistance (Hsp+) was demonstrated in matings between Streptococcus lactis ME2 (donor) and Streptococcus cremoris M43a (recipient), a derivative of M12R. Transconjugants were detected by transfer of Lac+ and were found to exhibit Nisr and harbor a 40-megadalton plasmid (pTR1040). Fifty-six percent of Lac+ transconjugants were resistant to the S. cremoris M12R lytic phage. Efficiency of plaquing for phage m12r . M12 on a phage-resistant transconjugant, T2r-M43a, was less than 4.3 X 10(-10). Five additional phages which were virulent for S. cremoris M12R and isolated from industrial sources failed to plaque on S. cremoris T2r-M43a. Mating experiments with T2r-M43a revealed that phage resistance was accompanied by high-frequency conjugation ability (Tra+) and the appearance of both pTR1040 and pTR2030 encoding Lac+ Nisr and Tra+ Hsp+, respectively, in transconjugants of S. lactis LM2302. Phage-sensitive Lac+ transconjugants of S. cremoris M43a (T2s-M43a) showed no conjugal ability. These observations confirmed that pTR2030 was present and responsible for the phage resistance and conjugal ability exhibited by the S. cremoris transconjugant T2r-M43a. Unlike the S. lactis LM2302 transconjugant carrying pTR2030, resistance of T2r-M43a to phage was not affected at high temperatures (35 to 40 degrees C) or destabilized in repeated transfers through a starter culture activity test. These results demonstrated that phage resistance conferred by pTR2030 in the S. cremoris transconjugant was effective against industrially significant phages under fermentation conditions normally encountered during cheese manufacture. [TOP OF PAGE]

  58. [Experience with bacteriophage therapy in nonspecific suppurative lung diseases]. [Russian]. Timoshchuk, I.I., Natsiashvili, E.I., Chanishvili, T.G., Meladze, G.D. (1985). Grudnaia Khirurgiia 11-13. [TOP OF PAGE]

  59. SIMULTANEOUS LOSS OF BACTERIOPHAGE RECEPTOR AND COAGGREGATION MEDIATOR ACTIVITIES IN ACTINOMYCES-VISCOSUS MG-1. Tylenda, C.A., ENRIQUEZ, E., Kolenbrander, P.E., Delisle, A.L. (1985). Infect. Immun. 48:228-233. Simultaneous loss of bacteriophage receptor and coaggregation mediator activities in Actinomyces viscosus MG-1.Actinomyces bacteriophages were used as tools to study coaggregation between actinomyces and streptococci. Four bacteriophage isolates, phages AV-1, AV-2, AV-3,and 1281, bound to coaggregation group A A. viscosus and to group E A. naeslundii. No binding to groups B, C, D, or F was observed. Only A. viscosus MG-1 was capable of supporting a productive infection by these phages. Spontaneously occurring bacteriophage-resistant mutants of A. viscosus MG-1 were isolated and were shown to fall into 2 classes. Class I mutants were resistant to all 4 phages, whereas class II mutants were resistant only to phage AV-3. In each case, strains resistant to a particular phage were unable to bind that phage, suggesting that a loss or alteration of the cell surface phage receptor had occurred. Both classes of mutants were unable to coaggregate with streptococci representing coaggregation group 1 and had also lost the ability to mediate 1 type of coaggregation with group 4 streptococci. Class II mutants also were unable to coaggregate with group 2 streptococci. Lactose-inhibitable interactions with other streptococci (groups 3 and 4) were unchanged in the mutants. The simultaneous loss of sensitivity to phage AV-3 and the ability to coaggregate with coaggregation group1 streptococci suggests the possibility of a relationship between these 2 cell surface structures. [TOP OF PAGE]

  60. Isolation of Actinomyces bacteriophage from human dental plaque. Tylenda, C.A., Calvert, C., Kolenbrander, P.E., Tylenda, A. (1985). Infect. Immun. 49:1-6. Human dental plaque samples were screened for the presence of bacteriophage for Actinomyces viscosus and Streptococcus sanguis. None of the 336 samples yielded phage for S. sanguis, but 10 contained virulent actinomyces phage. A high host cell specificity was observed in that one phage isolate infected only A. viscosus T14V, eight phage isolates infected only A. viscosus MG-1, and one infected both strains. None was capable of productively infecting various other actinomyces strains that represented the six actinomyces coaggregation groups. Because phage-containing samples occurred randomly in this survey, no correlation between the individual collecting the samples, dental clinic, or type of patient and the presence of phage in the sample was noted. Examination of one of the samples that yielded phage for the presence of a natural host strain for that particular phage resulted in the isolation of two strains which were identified as A. viscosus serotype II and Actinomyces naeslundii serotype I. This is the first report of an A. naeslundii host strain and actinomyces bacteriophage of human dental plaque origin. The finding of both phage and host strains in the same dental plaque sample along with the observation of high host cell specificity by these phage provide indicators that support an active role for actinomyces bacteriophage in oral microbial ecology. The use of these freshly isolated phage as probes to study actinomyces coaggregation properties is discussed. [TOP OF PAGE]

  61. Lytic viruses infecting a Chlorella-like alga. Van Etten, J.L., Burbank, D.E., Schuster, A.M., Meints, R.H. (1985). Virology 140:135-143. [TOP OF PAGE]

  62. A survey for viruses from fresh water that infect a eukaryotic Chlorella-like green alga. Van Etten, J.L., Van Etten, C.H., Johnson, J.K., Burbank, D.E. (1985). Appl. Environ. Microbiol. 49:1326-1328. [TOP OF PAGE]

  63. Mechanism of in vitro inactivation of Lactobacillus phage PL-1 by D-glucosamine. Watanabe, K., Kashige, N., Sasaki, T. (1985). Agric. Biol. Chem. 49:63-70. [TOP OF PAGE]

  64. ISOLATION OF FOUR BACTERIOPHAGES FROM THE MANGO BACTERIAL BLACK SPOT PATHOGEN XANTHOMONAS-CAMPESTRIS PATHOVAR MANGIFERAEINDICAE. WHITE, C.L., MELKJORSEN, G.B., DA, G.J., V (1985). Phytophylactica 17:11-14. Isolation of four bacteriophages from the mango bacterial black spot pathogen Xanthomonas campestris pathovar mangiferaeindicae.Four bacteriophages of Xanthomonas campestris pv. mangiferaeindicae were isolated from mango leaf litter. Three of the phages, Xm1, Xm3, and Xm4, were tailed and the other, Xm2, was filamentous. All four phages infected X. campestris pv. pruni; Xm1, Xm2 and Xm3 infected X. campestris pv. mangiferaeindicae. Phage Xm2 was more sensitive to temperature to low pH than the tailed phages. [TOP OF PAGE]

  65. Minimum bacterial density for bacteriophage replication: implications for significance of bacteriophages in natural ecosystems. Wiggins, B.A., Alexander, M. (1985). Appl. Environ. Microbiol. 49:19-23. [TOP OF PAGE]

  66. Virus persistence in groundwater. Yates, M.V., Gerba, C.P., Kelley, L.M. (1985). Appl. Environ. Microbiol. 49:778-781. [TOP OF PAGE]

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