Scope and History of Microbiology - kcesmjcollege.in · Microbiology is the Science that studies Microorganisms. Microorganisms, roughly, are those living things that are too small

Microbiology

What is

Mic

robio

logy?

Microbiology is the Science that studies

Microorganisms.

Microorganisms, roughly, are those living things

that are too small to be seen with the naked eye.

Microorganisms cannot be distinguished

Phylogenetically from ―Macroorganisms‖

For example, many fungi are microorganisms, as

well as all bacteria, all viruses, and most protists.

Microbiology is more a collection of techniques:

• Aseptic technique

• Pure culture technique

• Microscopic observation of whole organisms

A microbiologist usually first isolates a specific

microorganism from a population and then

cultures it.

Sca

le o

f M

icro

be

s

Types o

f M

icro

org

anis

ms

Bacteria

• a.k.a., eubacteria (―true‖ bacteria)

• a.k.a., domain Bacteria

Archaeabacteria

• a.k.a., domain Archaea

Single-celled members of domain Eukarya.

• Protozoa

• Microscopic Algae

• Microscopic Fungi

Viruses

Types: Bacteria

Description: eubacteria, archaeabacteria, Gram-negative,

Gram-positive, acid fast, cyanobacteria

Types: procaryotes, absorbers, wet conditions, animal

decomposers, cell walls, unicellular

Nutrient Type: chemoheterotrophs, photoheterotrophs,

chemoautotrophs, photoautotrophs

Durable state: endospores (some)

Diseases: tetanus, botulism, gonorrhea, chlamydia,

tuberculosis, etc., etc., etc.

Rob-Shaped Bacteria

Spherical Bacteria

Spiral-Shaped Bacteria

Spirochete

:

Borr

elia

burg

dorf

eri

Types: Cyanobacteria

Description: blue-green algae

Types: photosynthetic aquatic procaryotes, green lake scum,

cell walls

Nutrient Type: photoautotrophs

Durable state: ?

Diseases: none

Types: Algae

Description: photosynthetic aquatic eucaryotes, cell walls, both

unicellular and multicellular types

Types: brown, red, green, diatoms, dinoflagellates, euglenoids

Nutrient Type: photoautotrophs

Durable state:?

Diseases: Some poisonings associated with unicellular types: Alexandrium causes Paralytic Shellfish Poisoning (PSP), Dinophysis causes

Diarrhetic Shellfish Poisoning (DSP), Pseudo-nitzschia multiseries causes

Amnesic Shellfish Poisoning (ASP) [some would describe some as protists]

Types: Fungi

Description: yeasts (unicellular fungi), molds (filamentous

fungi)

Types: eucaryotes, absorbers, dry conditions, plant

decomposers, cell walls, ~100 human pathogens

Nutrient Type: chemoheterotrophs

Durable state: spores

Diseases: mycoses: candida, ringworm (pictured), athlete's

foot, jock itch, etc.

Types: Helminths

Description: Flatworms (platyhelminths), roundworms

(nematodes)

Types: metazoan (multicellular animal) parasites, engulfers

and absorbers

Nutrient Type: chemoheterotrophs

Durable state:?

Diseases:trichinosis, hook worm, tape worm (pictured are

scolex-heads of), etc.

Types: Protozoa (Protists)

Description: Unicellular and slime molds, flagellates, ciliates

Types: eucaryotes, parasites, engulfers and absorbers, wet

conditions, no cell wall, ~30 human pathogens

Nutrient Type: chemoheterotrophs (some classifications

include some photoautotrophs as well)

Durable state: cysts (some)

Diseases: malaria, giardiasis, amoebic dysentery, etc. (shown

are harmless--to us--protist components of pond water:

Amoeba, Blepharisma, Paramecium, Peranema, & Stentor)

Types: Viruses

Description: Not cells but enveloped or non-enveloped

Types: acellular, obligate intracellular parasites

Nutrient Type: not applicable

Durable state: virion particles, some can encase in durable

state of host

Diseases: common cold, flu, HIV, herpes, chicken pox, etc.

Binomial Nomenclature (1/3)

Examples: Escherichia coli, E. coli, Escherichia spp., and ―the

genus Escherichia‖

The genus name (Escherichia) is always capitalized

The species name (coli) is never capitalized

The species name is never used without the genus name (e.g.,

coli standing alone, by itself, is a mistake!)

The genus name may be used without the species name (e.g.,

Escherichia may stand alone, though when doing so it no

longer actually describes a species)

When both genus and species names are present, the genus

name always comes first (e.g., Escherichia coli, not coli

Escherichia)

Binomial Nomenclature (2/3)

Both the genus and species names are always italicized (or

underlined)—always underline if writing binomials by hand

The first time a binomial is used in a work, it must be spelled

out in its entirety (e.g., E. coli standing alone in a manuscript is

not acceptable unless you have already written Escherichia

coli in the manuscript)

The next time a biniomial is used it may be abbreviated (e.g.,

E. for Escherichia) though this is done typically only when

used in combination with the species name (e.g., E. coli)

The species name is never abbreviated

Binomial Nomenclature (3/3)

It is a good idea to abbreviate unambiguously if there is any

potential for confusion (e.g., Enterococcus vs. Escherichia)

These rules are to be followed when employing binomial

nomenclature even in your speech. It is proper to refer to

Escherichia coli as E. coli or even as Escherichia, but it is not

proper to call it coli or E.C.!

Failure to employ correct binomial nomenclature on exams will

result in the subtraction of one point (on 200-Point Scale) per

erroneous usage

When in doubt, write the whole thing out (and underline)!

Various BinomialsBacillus anthracis

Bacillus subtilis

Bdellovibrio spp.

Brodetella pertusis

Chlamydia trachomatis

Clostridium botulinum

Clostridium perfringens

Clostridium tetani

Corynebacterium diphtheriae

Escherichia coli

Gardinerella vaginalis

Helicobacter pylori

Haemophilus influenzae

Klebsiella pneumoniae

Lactococcus lactis

Legionella spp.

Listeria monocytogenes

Borrelia burgdorferi

Mycobacterium leprae

Mycobacterium tuberculosis

Mycoplasma pneumoniae

Neiseria meningitidis

Pasteurella pestis

Proteus vulgaris

Pseudomonas aeruginosa

Rickettsia prowazekii

Rickettsia rickettsii

Salmonella typhi

Serratia marcescens

Shigella dysenteriae

Staphylococcus aureus

Streptococcus pneumoniae

Treponema pallidum

Vibrio cholerae

Yersinia pestis

Neiseria gonorrhoeae

Cheat Sheet (1/2)Bacillus anthracis

Bacillus subtilis

Bdellovibrio spp.

Brodetella pertusis

Chlamydia trachomatis

Clostridium botulinum

Clostridium perfringens

Clostridium tetani

Corynebacterium diphtheriae

Escherichia coli

Gardinerella vaginalis

Helicobacter pylori

Haemophilus influenzae

Klebsiella pneumoniae

Lactococcus lactis

Legionella spp.

Listeria monocytogenes

Borrelia burgdorferi

Anthrax

Not pathogenic

Not pathogenic (to us, at least)

Lyme disease

Trachomas (blindness), etc.

Botulism

Gas gangrene & food poisoning

Tetanus

Diphtheria

Typhoid fever

Vaginitis

Stomach ulcer

Lung, ear infection, meningitis

Atypical pneumoniae (common)

Yogurt

Legionnaire’s disease

Damage to fetus

Whooping cough (pertusis)

Cheat Sheet (2/2)Leprosy

Tuberculosis

Atypical pneumonia

Meningitis

Plague (older name)

Wound infection

Opportunist (e.g., burns)

Typhus

Rocky Mountain Spotted Fever

Typhoid fever

Nosocomial infections

Traveler’s diarrhea

TSS, food poisoning, etc.

Most-common pneumonia

Syphilis

Cholera

Plague (newer name)

Gonorrhea

Mycobacterium leprae

Mycobacterium tuberculosis

Mycoplasma pneumoniae

Neiseria meningitidis

Pasteurella pestis

Proteus vulgaris

Pseudomonas aeruginosa

Rickettsia prowazekii

Rickettsia rickettsii

Salmonella typhi

Serratia marcescens

Shigella dysenteriae

Staphylococcus aureus

Streptococcus pneumoniae

Treponema pallidum

Vibrio cholerae

Yersinia pestis

Neiseria gonorrhoeae

Microbes & Ecology

Microbes are produces—they provide energy to ecosystems

Microbes are fixers—they make nutrients available from

inorganic sources, e.g., nitrogen

Microbes are decomposers—they free up nutrients from no

longer living sources

Microbes form symbioses (such as mycorrhizal fungi

associated with plant roots—though somewhat macroscopic,

the bacteria found in legume root nodules, etc.)

Microbes serve as emdosymbionts (e.g., chloroplasts and

mitochondria)

Microbes & Industry

Industry: Fermentation products (ethanol, acetone, etc.)

Food: Wine, cheese, yogurt, bread, half-sour pickles, etc.

Biotech: Recombinant products (e.g., human insulin,

vaccines)

Environment: Bioremediation

Each carton of Bugs+Plus provides easy to

follow step-by-step instructions, containers of

specially-formulated wet and dry nutrients and

a container of microbes cultured for their

ability to digest oil and other petroleum

derivatives.

Microbes & Disease

Microbes both cause and prevent diseases

Microbes produce antibiotics used to treat diseases

The single most important achievement of modern medicine

is the ability to treat or prevent microbial disease

Most of this course will consider the physiology of microbes

and their role in disease

The Germ Theory of Disease = Microbes cause disease!

(yes, it wasn’t so long ago that humans didn’t know this)

Normal Flora

These are the ~harmless microorganisms found on your body.

Every part of your body that normally comes in contact with

outside world (deep lungs and stomach are exceptions)

Brueghel: The Triumph of Death (1560)

Brief History Microbiology

Anton van Leeuwenhoek (1670s) = microscopy

Edward Jenner (1796) = vaccination against smallpox

Ignaz Semmelweis (1840s) = hand washing before surgery

Louis Pasteur (1860s) = repudiation spontaneous generation

Joseph Lister (1860) = father aseptic surgery

Robert Koch (1870s) = Koch’s postulates

Dmitri Iwanowski (1990s) = Inference of viruses

Alexander Fleming (1920s) = Penicillin

Stephen T. Abedon (2000s) = not one heck of a lot….

Hooke’s Microscope

Leeuwenhoek’s Microscope

RBCs

Edward Jenner – Smallpox Vaccine (1796)

Spontaneous Generation Myths

Snakes from horse hairs in stagnant water

Mice from grain and cheese wrapped in a sweater

Maggots from rotting meat

Fleas from hair

Flies from fresh and rotting fruit

Mosquitoes from stagnant pondwater

Eels from slimy mud at the bottom of the ocean

Locusts from green leaves

Raccoons from hollow tree trunks

Termites are generated from rotting wood

Redi’s Experiment

Problems Translating to Microbes

Hard to kill endospores—boiled broths not always sterilized

Concerns (invalid) that boiling altered broths so as to prevent

spontaneous generation

Concerns (invalid) that absence of air prevented

spontaneous generation

Concerns (invalid) that heating or chemically treating air

removed vital force from air thereby preventing spontaneous

generation

Basically, proponents of spontaneous generation had good

ol’ common sense on their side, but since their common sense

did not include any sense of microbiology, these spontaneous-

generation proponents were remarkably incorrect!

Pasteur’s Swan-Necked Flasks

President Garfield’s VertebraeOn the morning of July 2, 1881, Charles Guiteau

fired two shots at President James Garfield as he

entered a Washington, DC train station. One shot

grazed Garfield's hand. The second entered the

President's spine near the right 11th rib but did

not exit.

The x-ray, which would easily have pinpointed the

bullet's location, had not yet been discovered. So

the President's physicians did what all competent

physicians had routinely done in such cases.

They probed the entry wound with special

instruments designed for that purpose - but

without success.

The bullet remained lost inside the President.

Medical historians believe Garfield could have

survived his injury if the attending physicians had

washed their hands and used sterile instruments.

In 1881, though, such antisepsis techniques were

still under debate within the American medical

profession.

MicroDude Comes to Work

Cours

e S

tructu

re Grading:

• 3 midterms (200 points each x 3 = 600 points)

• 1 lab exams (200 points)

• 1 final exam (150 points comp + 150 points non-

comp = 300 points)

• 600 + 200 + 300 = 1100 points

Extra stuff:

• Daily reading and lecture quizzes (½ pt/question)

• ―30% rule‖ on all exam questions

See syllabus for details:

• www.phage.org/school_syllabus.htm

Laboratory PrimerJust reading a lab exercise is not the same as getting ready to

do a lab—you also need to outline for yourself, either mentally

or on paper, just what it is that you will be doing

I know that making such an outline with unfamiliar material is

not easy—that is why you need to look at your lab schedule,

where I attempt to guide you through what it is that you will

need to be doing

You have to try to remember that a culture that has settled will

need to be resuspended—and you have to not just go through

the motions: you actually need to resuspend it!

It may be that some of you have not had previous training in

using a microscope; after class today we therefore will have a

―microscope 101‖ session in B211

Link to Next Presentation

Acknow

ledgem

ents

http://www.colby.edu/biology/BI163/Bacteriappt/bacteriaarchaea.ppt