MCB 4403 EXAM 2

how are archaea and bacteria similar

both prokaryotic, normally have 1 circular chromosome, can be an/aerobic, auto/heterotroph, gram +/ -

how are archaea and bacteria different

different 16s rrna, NO peptidoglycan, have histones, and role as human pathogens in unclear

T/F: archaea are easy to culture

F

how are bacteria classified even if not able to grow in culture

by 16s rrna sequence

3 gram + phyla

firmicutes, actinobacteria, tenericutes

characteristics of gram + phyla

chemoheterotroph, can be grouped by GC content, include several human pathogens

high GC content phyla

actinobacteria

characteristics of actinobacteria phyla

aerobic, filamentous/ branching, high GC

genus of actinobacteria phyla examples

streptomyces

streptomyces characteristics

aerobic, high GC, common in soil, enzymes degrade organic compounds, source of common antibiotics, form spores

can steptomyces form endospores?

NO, only spores

low GC content phyla

firmicutes, tenericutes

which phyla breaks into categories based on ability to form endospores

firmicutes

endorspore forming firmicutes (2)

clostridium, bacillus

clostridium characteristics

obligate anaerobes, common in soil, ferment sugar (lack etc), can produce exotoxins

botulism, tetanus, gastroenteritis, and severe diarrhea are from exotoxins produced by the genus and phyla…

clostridium , firmicutes

bacillus characteristics

aerobes or fac. anaerobes, motile from flagella, source of common antibiotics, very few human pathogens

non endospores forming genus of firmicutes phyla (3)

lactobacillus, streptococcus, staphylococci

order of the lactic acid bacteria in firmicutes phylum

lactobacillales

characteristics of order lactobacillales

lack etc, use lactic acid fermentation, mostly aerotolerant anaerobes

genus examples of non endospore forming firmicutes (3)

lactobacillus, streptococcus, staphylococci

characteristics of lactobacillus

lactic acid bacteria, rod shaped, used in yogurt/cheese/pickled food/ beers

streptococcus characteristics

lactic acid bacteria, cocci shaped, can produce hemolytic exotoxins, common human pathogens (strep, rheumatic fever, pneumonia, tooth decay)

characteristics of staphylococci

cocci shaped, lactic acid OR facultative anaerobes, resistant to drying, salt tolerant, common microbes include S. aureus

S. aureus characteristics

component of human skin microbiome, derm conditions (ex acne, boils), agent of toxic shock syndrome, can cause food poisoning, has antibiotic resistant forms (ex MRSA)

gram - phyla (3)

proteobacteria, bacterioidetes, cyanobacteria

general qualities of proteobacteria

biggest phylum of bacterial species, evolved from photosynthetic ancestor, wide range of metabolisms, divided into 6 classes

class alpha proteobacteria examples

rhizobium, agrobacterium, rickettsia

rhizobium characteristics

symbiosis with legumes, can nitrogen fixate

agrobacterium characteristics

related to rhizobia but harmful, can cause tumors in plants via plasmids

rickettsia characteristics

aerobic organotrophs, some can oxidize intermediate metabolites, includes parasites that vector into humans via anthropods (ex typhus fever/ rocky mountain fever)

class betaproteobacteria example

neisseria

neisseria characteristics

cocci, aerobic, no gflagella, can colonize warm-blooded animals, can cause plaque in canines, can be pathogenic and cause gonorrhea and meningitis

enteric proteobacteria are in ____ class

gamma proteobacteria

enteric proteobacteria pathogens

escherichia, shigella, salmonella, yersinia (plague), enterobacter, klebsiella

enteric proteobacteria characteristics

rod shaped, mostly motile via flagella, facultative anaerobes and can do fermentation (mixed acid or butanediol)

gammaproteobacteria example

pseudomonas

pseudomonas charactertistics

straight or curved rods, polar flagella, ED pathway (aerobic), NOT capable of fermentation, diverse carbon and energy sources, pathogens mainly affect wounds and burns, can grow at low temp causing food spoilage

phylum bacteriodetes example

bacteriodes

bacteroides characteristics

obligate anaerobes, numerous microbe in human gut, ferment undigested food into lactate/ acetate, some are pathogenic and can cause peritonitis

cyanobacteria characteristics

perform oxygenic photosynthesis, contain thylakoids, can fix nitrogen, may cause algal blooms in phosphate rich water bc when decomposing, they deplete oxygen

genera examples of cyanobacteria

oscillatoria, anabaena