Lecture 7a- Microbial Diversity continued Flashcards by Unknown Unknown

what does the bacterial phyla proteobacteria consist of?

chemolithotrophs
chemoorganotrophs
phototrophs
facultative organisms (can switch from one metabolic lifestyle to another)

How well did you know this?

Not at all

Perfectly

what are the 6 classes of proteobacteria?

alphaproteobacteria
betaproteobacteria
gammaproteobacteria
deltaproteobacteria
epsilonproteobacteria
zetaproteobacteria

How well did you know this?

Not at all

Perfectly

what does alphaproteobacteria consist of?

pathogens and non-pathogens

How well did you know this?

Not at all

Perfectly

what is an example of a pathogenic alphaproteobacteria?

rickettsia rickettsii

How well did you know this?

Not at all

Perfectly

what are characteristics of rickettsia rickettsii? what type of pathogen? how are they transmitted? what can it cause?

obligate intracellular pathogen
carried by insects and transmitted by insect bites
causes rocky mountain spotted fever

How well did you know this?

Not at all

Perfectly

what is rickettsia rickettsii closest relative phylogenetically?

eukaryotic mitochondria

How well did you know this?

Not at all

Perfectly

what is an example of a non pathogenic alphaproteobacteria?

rhizobium leguminosarum

How well did you know this?

Not at all

Perfectly

what are characteristics of rhizobium leguminosarum?

forms root nodules on legume plants
symbiotic relationship
fixes nitrogen into a bioavailable form
plant provides nutrients and a home for the bacteria

How well did you know this?

Not at all

Perfectly

what are characteristics of betaproteobacteria?

metabolically diverse
pathogens or non-pathogens

How well did you know this?

Not at all

Perfectly

what is an example of a non-pathogenic betaproteobacteria? where does it live?

neisseria mucosa
lives on mucous membranes in human body

How well did you know this?

Not at all

Perfectly

what is an example of a pathogenic betaproteobacteria? what does it cause

neisseria gonorrhoeae
causes gonorrhea

How well did you know this?

Not at all

Perfectly

what are characteristics of gammaproteobacteria?

grow well in the lab and have become important research models

How well did you know this?

Not at all

Perfectly

what is a common example of a gammaproteobacteria?

E. coli

How well did you know this?

Not at all

Perfectly

what is E.coli? shape? oxygen requirements? type of flagella? ferments? where does it live? what is it an important indecator of?

gram negative, rod shaped
facultative aerobe
peritrichous flagella
ferments lactose to a mixture of acids and alcohols
lives in large intestine of warm blooded animals
serves as an important indicator of fecal contamination

How well did you know this?

Not at all

Perfectly

what is a second example of a gammaproteobacteria?

pseudomonas aeruginosa

How well did you know this?

Not at all

Perfectly

characteristics of pseudomonas aeruginosa? shape? motility? what is it naturally resistant to? what type of pathogen is it?

gram negative, rod shaped
motile through polar flagella
resistant to many antibiotics and disinfectants
opportunistic pathogen

How well did you know this?

Not at all

Perfectly

what is an opportunistic pathogen?

causes infections in immunocompromised patients
ex. respiratory tract infections in cystic fibrosis patients

How well did you know this?

Not at all

Perfectly

what is an example of deltaproteobacteria?

myxococcus xanthus

how do myxococcus xanthus move? how are they predatory? what happens when they are starved?

gliding motility, have adventurous motility and social, travel in waves
predatory because they release exoenzymes to lyse other bacteria for nutrients
when starved the cells migrate together to form fruiting bodies (differentiate into myxospores for dispersal)

what is a second example of deltaproteobacteria?

bdellovibrio bacteriovorus

what is the shape of bdellovibrio bacteriovorus? predator of what? gram + or -? how does it attack others?

curved
highly motile
predator of other proteobacteria and gram negative bacteria, penetrates cell wall and multiplies in the periplasm, this kills the cell

how is bdellovibrio bacteriovorus parasitic?

uses macromolecules obtained directly from the host

desulfovibrio is another example of deltaproteobacteria, what does it do?

reduces sulfate in oil, makes the oil go bad
obligately anaerobic

what is the epsilonproteobacteria? what is it famous for?

small class
famous for a few microaerophilic spirillum shaped pathogens

campylobacter jejuni is an example of epsilonproteobacteria, how is it transmitted? what is the most common cause? what does it cause?

frequently transmitted in undercooked chicken most common cause of foodborne illness causes bloody diarrhea and gastroenteritis

what does the bacterial phyla firmicutes consist of? gram + or -? what type of bacteria is it? what type of anaerobe?

gram positive cell wall (one of two phyla with this) low guanosine cytosine gram positives includes lactic acid bacteria aerotolerant anaerobes that produce lactic acid as an end product of fermentation

what are two examples of lactic acid bacterial firmicutes? what do they do?

lactobacillus delbrueckii: yogurt production streptococcus pyogenes: cause of strep throat, scarlet fever and flesh eating disease

what are two examples of non lactic acid bacterial firmicutes?

staphylococcus aureus staphylococcus epidermidis

what are characteristics of staphylococcus aureus? what type of aerobe? what type of arrangement? where do they live? what do they cause?

facultative aerobe that forms characteristic grape like clusters lives on skin halotolerant (yellow on mannitol salt agar) frequent cause of nosocomial infections

what does halotolerant mean?

can be isolated using media with high NaCl (ex. mannitol salt agar, produces acids (yellow))

where are staphylococcus epidermidis located?

skin distinguished on mannitol salt agar as red, thus no acid production

some firmicutes are endospore forming, what two genus within the firmicutes are endospore forming?

bacillus clostridium

what is the main difference between bacillus and clostridium genus?

bacillus are aerobic endospore formers clostridium are strictly anaerobic endospore formers

are endospore forming firmicutes pathogenic or non- pathogenic? where do they live?

most are non- pathogenic saprophytic soil organisms some are dangerous pathogens

bacillus subtilis is a species in the genus bacillus, what is so important about them?

used as a model organism for gram positive cell structure, cell division and differentiation into endospores

clostridium botulinum is a species in the genus clostridium, what kind of anaerobes are they? what do they produce?

strict anaerobe with a fermentative metabolism produces a variety of exoenzymes to breakdown plant material produces a deadly neurotoxin and when consumed causes botulism

clostridium botulinum can also grow in anaerobic canned foods, how can we prevent this?

proper canning procedures must either reach temp above 120 degrees celsius to destroy endospores or must include enough acid or sugar to prevent germination

there are several deeply branching phyla that consist of hyperthermophilic bacteria, what does this suggest?

that the last universal common ancestor (LUCA) may have been a hyperthermophile

what are the two famous hyperthermophilic bacterial species?

thermus aquaticus deinococcus radiodurans

what microorganism class are thermus aquaticus?

thermophilic chemoorganoheterotroph

what is the importance of thermus aquaticus species?

allows DNA synthesis reactions in the lab to be carried out quickly at high temperatures and is an essential tool for polymerase chain reaction

what is unique about deinococcus radiodurans species?

form pairs or tetrads extremely resistant to radiation, thus in response to radiation two cells will fuse together to facilitate repair

what gram stain do deinococcus radiodurans take on?

have a gram negative cell wall but stain gram positive because of thick peptidoglycan