★ microbio ; exam 1 content (bio116)

so many terms siggghghghg.. based frm some openstax but many prof slides..

francesco redi

created the theory of biogenesis while opposing the spontaneous theory that maggots came from meat

robert koch

proves germ theory of disease, developed postulates

salk and sabin

salk formed the polio vaccine with a inactivated polio virus, sabin made a live polio vaccine; aka virus is altered

pasteur

developed pasteurization and proved fermentation from yeast

germ theory of disease

microorganisms cause disease (in people, plants, animals) ; koch and pasteur

theory of biogenesis

life came from life ; redi’s maggots came from flies

koch’s postulates

microbes in sick vs none in healthy → microbe in sick mouse is culturable → cultured microbe can make healhty mouse sick → new sick mouse has the same microbe that is cultured again

why aren’t koch’s postulates used as much today?

asymptomatic (no symptom) individuals and viruses cannot be cultured without a host

archaea (domain)

unicellular, prokaryote with distinct metabolism that withstands extreme conditions

pasteurization

a process used to kill microorganisms responsible for spoilage

binary fission

a process that prokaryotes use for cellular growth instead of mitosis

peptidoglycan

a prokaryote-unique structure that forms the layer of the cell wall. composed of polymers of alternating nam and nag

compare and contrast gram negative and gram positive

negative: pink stain, LPS outer membrane with thin pep layer | positive: purple stain, thick pep layer

nag

n-acetyl glucosamine

nam

n-acetyl-muramic acid, has 2-5 amino acids attached

penicillin

beta lactam antibiotic that inhibits transpeptidase to form cross bridges in transpeptidation

glycocalyx

a sugar coat that is slimy and cohesive. significant component of biofilms (aids in formation), prevents from drying and protects from phagocytes

capsules

tightly bounded sugar coat of glycocalyx that protects bacteria from phagocytes

inclusions

a cytoplasmic structure in prokaryotes that stores granules of sugar, lipid: storage

endospores

a bacterial structure, being a thick coat that is hard to kill; requires a autoclave at 121 C

steps of gram staining

fixation → crystal violet dye → iodine treatment → decolorization → counter stain safranin

cell wall

semirigid casing that give structural support and shape for cell; bacteria with this do well in hypotonic solutions

how may microbes resist penicillin?

coating that blocks access (cell wall), contains receptors that bind to antibiotic

flow of protein synthesis

ER (rough: protein, smooth: lipid) → golgi → plasma membrane

classes of eukaryotes

fungi, protozoans, helminths, arthropod vectors

protozoans

microbe that r usually in watery environments w a structure that expels water taken in a fresh water environment

trophozooite

active feeding protozoan ; flagellates r examples

dimorphic

grows in nature but grows in yeast in the body ; mold is a example

cestodes

tape worms that are long and segmented, has a holdfast structure that attaches to the intestine (scolex),, proglottids that produce eggs as they mature → pass in stool

trematodes

“flukes”, leaf like body; non segmented,, seeks out an immediate host → infects us → creates infection → passes in waste

nematodes

round worms, v diverse ; ex pinworms which causes itchy 🍑

arthropod vectors

animals w '“jointed” feet that bite and transmit microbes (mosquito pmo)

unique features of a fungal cell wall

mannoproteins, beta glucans, chitin, ergosterol

bacteria preferred pH

6.5-7.5 (neutral-ish)

mesophiles

grow best @ mod. temp (25-40, slightly higher than us), most lab microbes

psychrophile

adapted to survive n grow @ cooler temp, even in fridge (25 C<) ; ex is listeria

thermophiles

adapted to survive n grow at high temp ; ex is thermus aquaticus @ 60 F from oceanic vents

halophiles

bacteria that thrive in hypertonic solutions ; ex r vibrios like v. cholera

usual bacteria reaction to hypertonic

slow/stops growth as salt preservative in meat

usual preference of osmotic pressure

isotonic

obligate aerobe

uses molecular oxygen as the final e^- acceptor in catabolism ; ex is pseudomonas spp

obligate anaerobe

no oxygen but organic molecule takes the role instead ; ex is clostrida, which grows in brewer jar

facultative anaerobes

grows with or without oxygen, usually fermenters like E. coli

microaerophile

grows in low oxygen conditions and higher carbon dioxide

fastidious organism

‘picky’, hard to grow; may need enriched media to grow

superoxide dismutase

enzyme that chemically alters toxic oxygen free radicals + high toxic energy singlet oxygen to less toxic hydrogen peroxide

catalase

enzyme that chemically changes hydrogen peroxide to oxygen and water

zygomycetes

sex spore are zygospores | asexual: sporangiospores

ascomycetes

sex spore are ascus (sac) | asexual: conidiospores

basidiomycetes

mushrooms, sexual spore @ end like ‘basidium’

deuteromycetes

no sexual mechanism noted, many human pathogens (ex candida)

glycolysis

linear pathway that takes place in the cytoplasm (anaerobic)

krebs cycle

cyclic pathway that takes place in the mitochondrial matrix (aerobic)

electron transport + chemiosmosis

takes place in the inner mitochondrial membrane, makes most atp (aerobic)

fermentation

anaerobic process that produces little ATP, usually fermenting sugars n other substrates that end with lactic + acetic acid

other way bacteria undergo fermentation (e. coli, bacillus)

using nitrogen electron acceptors to regenerate NAD

other metabolisms than glucose?

lipids (glycerol + fatty acids), nucleic acids, etc..