prokaryotes

Question 1

what are the groups prokaryotes are divided into

Answer 1

bacteria and archea

Question 2

how do we define bacterial species

Answer 2

-species concept
-not based on interbreeding or regions
-nucleotide sequence (gene/genome)

Question 3

how did we used to define bacterial species

Answer 3

-morphological features
-shape, staining patterns, biochemical tests, growth patterns

Question 4

how much of the DNA need to be the same to be considered the same species

Answer 4

97% 16S rRNA identity

Question 5

how much of the DNA need to be the same for the species to used to have been the same

Answer 5

70% homology by hybridization

Question 6

what is the average nucleotide identity

Answer 6

96%

Question 7

based on staining patterns in lecture two how did we used to divide bacteria into groups

Answer 7

gram pos ( plus acid fasting positive) and gram negative

Question 8

gram positive bacteria

Answer 8

-low G+C
-high G+C
-acid fast bacteria

Question 9

gram neg bacteria

Answer 9

protoeobacteria

Question 10

why is it hard to devide bacteria based off staining

Answer 10

-pattern is sometimes wrong
-chlamitia-no cell wall but has peptiglycan
-mycoplasm- co cell wall and no peptiglycan
-rickettsia- too small
-deep brancing bacteria-stain gram + with a top layer

Question 11

what are protobacteria

Answer 11

-purple bacteria and their relatives
-16S rRNA gene sequencing
-gram -
-subdivided into
-alphaprotobacteria
-betaprotobacteria
-gammaprotobacteria
-deltaprotobacteria
-epsilonprotobacteria

Question 12

alphaprotobacteria

Answer 12

-olingotroph (grow in low nutrient environment)
-can N fix
-chlamydia and rickettsiae
-obligate intracellular pathogens

Question 13

chlamydia life cycle

Answer 13

-alphaprotobac
-over 72 hrs
-cell releases elementry bodies (active, infectious form)
-12 hrs go into and infect epithelial cell
-start turing into reticulate bodies(metabolically active)
-24 hrs inclusion
-start turning into elementary bodies
-once all elementary then they are released

Question 14

betaproteobacteria

Answer 14

-eutrophs (grow in high nutrient environment)
-nessieria and bordetella pertussis

Question 15

gammaprotobacteria

Answer 15

-largest and most diverse group
-aerobic or facultative aerobes (can switch to ferm if O2 isnt present)
-has different families: pseudomonaceae, pasteurellaceae, vibrionaceae, legionellaceae, enterobacteriaceae
-coliforms (ferments lactose-acid and gas production) (E. coli)
-non-coliform (do not ferment lactose or incomplete-no acid or gas)(salmonella)

Question 16

deltaprotobacteria

Answer 16

-sulphate-reducing bacteria (SRB)
-meaning final electron acceptor in ETC
-anaerobic resperation
-bdellovibrio (vampire/predatory bacteria)
-myxobacteria (slime bacteria) (motile and highly social, multicellular “fruiting bodies, have myxospores(metabolically inactive round cells, thick walled, survive harsh conditions))

Question 17

epsilonprotobacteria

Answer 17

-smallest group
-microaerophillic (need O2 but not too much or they die)
-campylobacter and helicobacter

Question 18

how would you tell alphaprotobacteria form betaprotobacteria

Answer 18

based on their ability to grow in low (oligotroph) or high (eutroph) nutrient environments

Question 19

non-protobacteria, gram-, spirochetes

Answer 19

-long, thin, spiral shaped
-difficult to gram stain
-dark field fluorescent microscope
-difficult to grow in the lab
-axial filament for motility
-borrelia (lyme) and treponema (syphalis)

Question 20

non-protobacteria, gram -, cytophaga, fusobacterium, and bacteroides

Answer 20

-phylogenetically diverse
-rod shaped bacteria
-anarobic (strict or aerotolerent)
-fermenters

Question 21

non-proteobacteria, gram -, planctomycetes

Answer 21

-aquatic environments
-budding cell division
-swarmer cells + sessile cells

Question 22

non-proteobacteria, gram -, phototrophic bacteria

Answer 22

-cyanobacteria
-oxygen producing

Question 23

how do sparochetes differ from bacteroides

Answer 23

its shape- spiral vs rods

Question 24

actinobacteria

Answer 24

-high G+C
-gram pos
-thin filamentous barnching rods to coccobacilli
-large and complex to smallest and independently living organisms
-found in the soil,but some are aquatic
-majority are aerobic but not all
-acid fast bacteria

Question 25

firmicutes

Answer 25

-low G+C
-gram pos
-clostridia
-lactobacillales
-bacilli
-myocoplama

Question 26

clostridia

Answer 26

-fermicutes
-clostridium
-abligate anarobes
-endospores

Question 27

lactobacillales

Answer 27

-lactic acid bacteria
-listeria, lactobacillus, leuconostoc, enterococcus, and streptococcus

Question 28

bacilli

Answer 28

-aerobic or facultative anarobes
-endospore former
-staphylococcus
-facultative anaerobes

Question 29

mycoplasm

Answer 29

-firmicutes
-no cell wall, no peptidglycan
-not gram stainable
-small, pleomorphic

Question 30

how do you differentiate clostridia from bacilli

Answer 30

the requirement of O2 (obligate anaerobe vs obligate aerobe/facultative anaerobe

Question 31

deep branching bacteria

Answer 31

-evolved form ancient and now extinct life forms
-living fossils?
-three examples: aquificae (adapt to harshest conditions), thermotogae (anarobic, stain gram negative, sheath like outter mem)
-deinococcus radiodurans (polyextremeophiles)

Question 32

how to tell the difference between thermotogae form gram neg bacteria

Answer 32

the composition of the outer membrane