Microbiology Ch 1 - Ch 3

• 1665 observed cork cells using compound lens.
• termed word "cells" began "cell theory"

• first observations of living cells taken from his own body.
• first microscope using magnifying lens

some forms of life could arise spontaneously from nonliving matter

• fleas from hair
• flies from fresh and rotting fruit
• locusts from green leaves
• raccoons from hollow tree trunks
• termites from rotten wood
• eels from slimy mud at the bottome of bodies of water
• mosquitoes from stagnant pond water

Pasteur

filtered air through cotton plug showing that filterable particles cause contamination of sterile broths.

• trapped air escapes from open end flask (sterile broth)
• bacteria/dust from air settle in bend of flasks
• broth sterile indefinately
• flask tilted so sterile broth makes contact with contaminated bacteria/dust from air
• bacteria multiplies in broth

if he used vegetable broth or soil broth there would have been endospores present and that has a bacterial state that is very hard to kill

study of microorganisms

• aseptic technique
• pure culture technique
• microscopic observation of whole organism's

establish system of scientific nomenclature, where each organism has 2 names, the genus and species.

• genus = first word, capitalized
• species=italicized, lower case

• 1. bacteria
• 2. archaea
• 3. eukarya
• 4. Nucleocytoplasmic Large DNA Virus (NCLDV) NEW DOMAIN

• eubacteria
• gram negative
• gram positive
• acid fast
• cyanobacteria (blue green algae)

• 1. chemotrophs- use chemical for energy
• 2. phototrophs- use light for energy

• tetanus
• botulism
• gonorrhea
• chlamydia
• TB

some form endospores

• (diplo)- 2
• (strepto)- row or line
• (staphylo)- cluster

2 sphere shaped bacteria

line or row of sphere shaped bacteria

cluster of sphere shaped bacteria

green/blue

• prokaryotic
• lack peptidoglycan
• live in extreme environments
• none are known to cause disease

• methanogens- produce methane as waste product of respiration
• extreme halophiles- extreme salty environment
• extreme thermophiles-extreme hot, sulfurous environment

• prokaryotes
• simple single cell (unicellular),
• genetic material not enclosed in nuclear membrane,
• peptidoglycan cell walls
• reproduce by binary fusion
• appear in various shapes:

• * Bacillus- rod like
• *Coccus- spherical or ovoid
• *Spiral- corkscrew or curved

• eukaryotes
• chitin cell wall
• use organic chemical for energy

• unicellular: yeast
• multicellular: mold/mushrooms

filaments that consist of masses of mycelia in molds adn mushrooms

• eukaryotes
• unicellular
• slime molds, flagellates and ciliates
• absorb/ingest organic chemical for energy
• some form durable cysts

• malaria
• giardia
• amoebic dysentery

• eukaryotes
• flatworms, roundworms, nematodes
• some are multicellular animal parasites
• microscopic stages in life cycle

• trichinosis
• hook worm
• tape worm

• eukaryotes
• brown, red, green
• di-atoms
• in larvae stage are swimmers
• cellulose cell walls
• uses photosynthesis for energy

some poisoning associated with unicellular types

• not cells but some have lipid membranes and require cells to reproduce
• acellular, obligate intracellular parasites
• cant cure only treat s/s

• cold'
• flu
• HIV
• herpes
• chicken pox

consist of DNA, RNA, protiens

• CJD
• Kuru
• Alpners syndrome
• (infant) Scrapie
• (infant) CWD
• ALL ARE FATAL

• produce energy to ecosystem
• make nutrients avail from inorganic sources
• decomposers-liberate nutrients from no longer living sources
• form symcioses (mycorrhizal fungi assoc with plant root, found in legume nodules)
• serve as endosymbionts (chloroplast, mitochondria)

• fermentation products -cheese, hyogurt, bread, pickles
• biotech- recombinant products such as insulin/vaccines
• bioremediation- microbes used at max. levels to degrade other microbes

• 1796- Edward Jenner - innoculated person w/ cowpox and they were then protected from small pox (immune) and coined term Vaccination
• 1860- Joseph LIster- inspired by Pasteur, used chem disinfect to prvent surgical wound infect.
• 1876- Robert Koch- proof that bateria causes anthrax and proved experimental steps to prove specific microbe causes specific disease (germ theory of disease

• prevent pathogens
• produce growth factors such as folic acid and vit K
• hygeine hypothesis- we are too clean so immune system out of whack.

ability for body to ward off disease

when pathogen overcomes host's resistance

• 1 um = 10 ^ -6 = 10 ^ -3 mm
• 1 nm= 10 ^ -9 = 10 ^ -6 mm
• 1000 nm = 1 um
• 0.001 um = 1 nm

1 lens

• images from objective lens (eye) magnifies through second lens (object)
• total magnification = objective lens X ocular lens

• lenses to distinguish two points
• shorter wavelengths of light provide greater resolution

• immersion oil d/t light not bouncing or bending
• blue light
• using electrons

light bending ability of medium

keep light from bending so it doesnt miss the small high magnification lens

• dark objects visible against bright background
• light is reflected off specimen adn doesnt enter objective lens

• light objects visible against dark background
• light reflected off specimen enter objective lens

brightfield illumination

accentuates diffractrion of light that passes through specimen

• uses UV light
• fluorescent substance absorb UV light and emit visible light
• cells may be staind with fluorescent dye

• uses fluorochromes and laser
• laser illuminates each plane in specimen to produce 3 D image

• electron Microscopy- uses electrons (shorter wavelength then light)
• Scanning Probe and Atomic Force Microscopy (creates image with similar resolution but does not use electrons)

• electron microscope that transmits electrons through substance
• specimen may be stain with heavy metal salt
• sliced and very thin sections

• electron microscope where electron gun fires beam of electrons
• electrons bounce off surface of specimen
• results in 3 D image

• uses metal probe to scan specimen
• resolution 1/100 of atom

• uses metal and diamond probe inserted into specimen
• 3D image

• thin film of soln smeared on slide
• smear is "fixed" or attached to slide (kills microbes- overheating can distort shape)

create contrast

• results from differences in index of refraction between specimen and background
• or results with difference in index of refraction within specimen and number of visible colors in specimen

black / white

• black / white color
• stains
• closing the iris diaphragm

• use of a single basic (alkaline) dye
• mordant may be used to hold stain or coat specimen

• coating used to hold stain on specimen
• makes specimen appear larger
• iodine soln.

• gram stain
• acid fast
• negative

• a) gram positive
• b) gram negative

penicillin and detergents

gram negative bacteria more resistant to antibiotic

• gram positive will be stay purple color
• gram negative will stain red

• add alkaline crystal violet (simple stain)
• add iodine (mordant - attach to crystal violet) all cells purple
• decolorize with alcohol (crytal violet washes out gram negative cells)
• counter stain with safranin
• gram positive remains purple
• gram negative counterstains red

cells that retain basic stain in presence of acid- alcohol

loose basic stain when rinsed with alcohol and are usually counterstained with different basic stain.

acid fast staining

• usefull to visualize capsule around bacteria
• stains background dark (doesnt stain bacteris only background)
• less distortion of cells then other special stains
• no heat used

bacteria is sticky if it has a halo around it and wants to stick. if no halo, then not sticky. If it is sticky then it has a sugar coating around capsule

• protist/protozoa
• algae
• fungi
• helminth

• Toads, snakes and mice being born of moist soil
• Flies emerging from manure
• Maggots (larvae of flies) could arise from decaying corpses.
• Snakes from horse hairs in stagnant water
• Mice from grain and cheese wrapped in a sweater
• Maggots from rotting meat
• Fleas from hair
• Mosquitoes from stagnant pond water
• Eels from slimy mud at the bottom of bodies of water
• Locusts from green leaves
• Termites from rotten wood
• Raccoons from hollow tree trunks

1668 maggots did not arise spontaneously from decaying meat