Scope and History of Microbiology

Important words and concepts from Chapter 1, Black, 2002 (3/28/2003):

by Stephen T. Abedon (abedon.1@osu.edu) for Micro 509 at the Ohio State University

Course-external links are in brackets

Click [index] to access site index

Click here to access text’s website

(1) Chapter title: Scope and History of Microbiology

(a) Throughout this course (i.e., these notes) I will be doing my best to supply you with links to supplemental material found on the World Wide Web

(i) If you have additional interest in presented material or need additional exposure to concepts, consider following these links (on line, of course)

(ii) I will regularly include Google searches that may be followed for abundant additional information on material—however, always keep in mind that your first, best reference will usually be your text book

(iii) There also exists an index to this site called MicroPort that is found at http://www.phage.org/microbiology.htm or by pressing [index] throughout these notes

(b) Studying tips:

(i) Read over assigned material in your text before coming to lectures

· Read your text well so that, minimally, you have made an attempt at understanding the presented concepts

(ii) Read over the supplied lecture notes (i.e., these)

· Read lecture notes well so that you have made an attempt at understanding the presented concepts

· Make an effort to memorize the supplied vocabulary

(iii) Come to class prepared to ask questions

(iv) After class, organize the material, integrating the notes that you take during class

(v) REMEMBER, CLASS ONLY MEETS TWICE A WEEK SO BLOWING OFF A LECTURE OR NOT STUDYING PRIOR TO AND AFTER A LECTURE IS EQUIVALENT TO BLOWING OFF HALF OF A WEEK OF STUDYING

(vi) Study for the first exam in this course harder than you have ever studied for an exam before

· Triage the material you will be studying such that you don’t waste your time studying the material you already know/understand

· Make sure that you have extensively been through the material and have organized it before you begin to study

· Don’t put off your studying to the last minute

· Don’t count organizing and learning your material as exam study time—studying for an exam involves making sure that you have memorized and can lucidly regurgitate the material, not simply becoming familiar with it

· Simply reading over notes again and again is not necessarily equivalent to doing the hard work of learning

(vii) Don’t forget that labs are worth a good chunk of your grade

· Don’t blow off labs

· Read labs before you come to laboratories and as you are doing them

· Also read your lab schedule for tips on how to do labs

· Labs are much (much, much) easier to do when you are familiar with them; I will be able to tell when you are unfamiliar with labs; I will reserve the right to quiz on lab preparation if I get the impression that students are coming to laboratories unprepared

· Answer questions and make notes while the material is still fresh in your mind

(c) For tips on how to study for microbiology, see: [microbiology and "study tips" (Google Search)] [microbiology study tips (need to skip down a bit to find) (Gary E. Kaiser)]

(d) Links to other on-line microbiology courses (and course-like sites): [microbiology and course (Google Search)] [Microbiology Webbed Out (Kenneth Todar)]

(e) Microbiology link collections can be found at: [microbiology links (Google Search)]

(2) What is Microbiology?

(a) Microbiology is "the study of microbes, organisms so small that a microscope is needed to study them."

(b) Microbiology, as a science, may be differentiated along organism lines ("the variety of kinds of microbes") and in terms of techniques and goals ("the kind of work microbiologists do")

What is Microbiology?

· Microbiology is the study of microorganisms

· Microorganisms, roughly, are living things that are too small to be seen with the naked eye

· Microorganisms cannot be distinguished phylogenetically from “macroorganisms” (see variety of microorganisms, below)

· Microbiology is more a collection of techniques: aseptic technique, pure culture technique, microscopic observation of whole organisms, etc.

· Microbiologists isolate specific, culturable microorganisms from wild populations, then study them (or, alternatively, study them in situ without culturing them)

(c) [Microbiology is the study of organisms too small to be seen with the naked eye. Originally, emphasis was placed on harmful microorganisms which cause disease or spoilage of beverages and food, but it is now recognized that many microbes have essential roles in our ecosystem or can be used to accomplish beneficial tasks. Human history is full of examples of major devastations caused by bacteria and viruses. Some of these historically important diseases still occur, such tuberculosis and yellow fever. Microorganisms are evolving to cause new infectious disease problems such as Lyme disease and AIDS, which capture public attention. Control and eradication of infectious diseases remain important goals of many microbiologists. The recognition that microorganisms were responsible for what was earlier thought to be "spontaneous generation" opened the door to industrial (pharmaceutical, chemical, energy) and food microbiology, technologies which contribute substantially to today's way of life. Microorganisms in soil and water are essential in the transformation of carbon, nitrogen, oxygen, sulfur and iron to products needed by plants and animals. In various ways, microbes participate in environmental cycling and degradation and global change. In the last few decades, microorganisms have been recognized as ideal model systems for the study of basic biological processes. ¶ More recently, microbiologists have brought an exciting dimension to the study of biology through the use of genetic engineering techniques and highly specific protein (antibody) molecules. Accomplishments in these areas already have led to enormous benefits for the human race, but there are many more challenges to be conquered through these kinds of studies. In the future, studies in space microbiology may help to reveal if there is life on other planets and the role of microorganisms in closed systems. Today, one can truly say that the potential for microbiology to benefit human and animal health and life has never been better. (CSU Department of Microbiology)]

(d) [microbiology (Google Search)] [index]

(3) The variety of kinds of microbes (microbes, microorganisms)

(a) Microbes are typically (but certainly not always) either unicellular organism (e.g., bacteria) or acellular "organisms" (e.g., viruses)

(b) Typically a microbiologist will differentiate microbes into the following categories:

(i) Bacteria

(ii) Algae

(iii) Fungi

(iv) Viruses

(v) Protozoa

(vi) Helminths

(d) Additional, external links: [index]

(i) [microbe and SEM (links to electron microscopic images of microbes) (Google Search)]

(ii) [big picture of infectious diseases (Gary E. Kaiser)]

(iii) [microbe portrait gallery (pictures of microbes) (Microbe World)]

(iv) [universal tree (MicroDude)]

Supplemental Material – Types of Microorganisms & their General Properties
organism:	types:	description:	Nutrition type (-trophs):	durable state:	some diseases:
algae:	brown, red, green, diatoms, dinoflagellates, euglenoids	photosynthetic aquatic eucaryotes, cell walls, unicellular and multicellular	photoauto-	---	---
bacteria:	eubacteria, archaeabacteria, Gram-negative, Gram-positive, acid fast, cyanobacteria	procaryotes, absorbers, wet conditions, animal decomposers, cell walls, unicellular	chemohetero- photohetero- chemoauto- photoauto-	endospores (some)	tetanus, botulism, gonorrhea, chlamydia, tuberculosis, etc., etc., etc.
cyano-bacteria:	blue-green algae	photosynthetic aquatic procaryotes, green lake scum, cell walls	photoauto-	---	---
fungi:	yeasts (unicellular fungi), molds (filamentous fungi)	eucaryotes, absorbers, dry conditions, plant decomposers, cell walls, ~100 human pathogens	chemohetero-	spores	mycoses: candida, ringworm, athlete's foot, jock itch, etc.
helminths:	Flatworms (platyhelminths), roundworms (nematodes)	metazoan (multicellular animal) parasites, engulfers and absorbers	chemohetero-	---	tape worm, trichinosis, hook worm, etc.
protozoa:	Unicellular and slime molds, flagellates, ciliates	eucaryotes, parasites, engulfers and absorbers, wet conditions, no cell wall, ~30 human pathogens	chemohetero-	cysts (some)	malaria, giardiasis, amoebic dysentery, etc.
viruses:	Enveloped, non-enveloped	acellular, obligate intracellular parasites	not applicable	virion particles, encased in durable state of host	common cold, flu, HIV, herpes, chicken pox, etc.