Topic 4b: Microbial Diversity

Question 1

what are phototrophic bact

Answer 1

chlorophyll based

Question 2

phylum cyanobact

Answer 2

oxygenic (PS I and II); use E of light to make org compounds
–have thylakoid mems and carboxysomes (have intermol struct where photosynth occurs)
co2 fixers
not all phototrophic
g neg
blue/green algae
most obligate photolithotophs (water = e donor)
-may use gas vacuoles to locate in water (to get to right dist from light)
-or gliding motility or ligh sensory organs

-many = N fixers

Question 3

why are cyanobact imp

Answer 3

do ab 1/3 of all co2 fixation
have biofuel potential

Question 4

purple sulfur bact

Answer 4

anaerobe, usu photolithoautotrophs
-use H2S = e D (litho)
–gets fully ox’d to S stored in granules
-fix co2 (auto)
PSII

split into chromatiacaea (sulfur granules internal to cell) and extothiorhodospiraceae (sulfur granules externally stored)

Question 5

purple non sulfur bact

Answer 5

more w protobact
phylogenetically and metabolically diverse
usu photoheterotrophs
-can use C from organis as e source and other things
anoxygenic photosynthesis
PSII

*dif than sulf bact based on mems where photosynth happens
–no xtra photosynth mems (doing it all in PM)

Question 6

chloroboi

Answer 6

green sulf bact
anoxygenic phototrophs
obligate anaerobic photolithoautotrophs
e D = H2S, elemental sulfur, hydrogen

sulfur granules external to cell (like purp)
have organelles (struct that contains their photosynth)
–chlorosome (contains photosyn pigments)
PSI
-can use gas vesicle to position selves
have diverse morphology

Question 7

proteobact

Answer 7

g neg
diverse morph
photoautotrophs, chemolithotrophs, chemoheterotrophs
5 classes

Question 8

alpha proteo

Answer 8

most abundant bact in oceans
oligotroph - can live on low nuts

Question 9

what are the 2 orders of alphaproteo

Answer 9

rickettsiales
-g neg
-parasitic or mutualistic
-lack glycolytic pathways (get away w this bc para/mut t/f rely on s/o else to get food)
-have tca cycle
-cause typhus (affected napoleon)

Rhizobiales:
-fix N and grow symb w plants
-agrobact (plant pathogen)
-brucella (animal pathogen)

Question 10

beta proteo

Answer 10

Chemoheterotrophs, photolithotrophs, chemolithotrophs

Question 11

2 orders of beta proteo

Answer 11

Neisseriales:
-non motiles, aerobic, g neg
-causes meningitus (inflammation to brain)
-causes gonnorhea (STI w antibiotic resisyance)

Burkholderiales
-includes Bordetella (mammal parasite, causes pertusssis)

Question 12

gamma proteo

Answer 12

physiologically diverse
4 main orders (legionellales, pseudomonadales, enterobacteriales, vibrionales)

Question 13

g proteo - legionellales

Answer 13

intracellular pathogens w dimorphic lifestyles (2 cell types)
-can form highly infectious cysts called mature intracellular forms (MIFs)
–causes pnemonia

Question 14

g proteo - pseudomonadales

Answer 14

use entner-doudoroff

can use p. aeruginosa to study biofilms
-obligate respirer (use ETC); internal e A varies
-opportunistic pathogen, cystic fibrosis
-can degrade polyaromatic hydrocarbons

photorhabdus luminescens
-angels glow (better prognosis)
-nemotoad and bact = mutualistic and toxins to break insects made wounds cleaner

Question 15

endo v exo toxin

Answer 15

endo - LPS (on surface of cell)
exo - made and secreted (create toxin and pumped into env)

Question 16

g proteo - enterobacteriales

Answer 16

use embden myerhoff
divided in ferm prods
-mixed acid or butanediol (ethanol and co2; less acidic)

common = e coli, salmonella, shigella, klebsiella, yersinia

Question 17

what caused plague/black death

Answer 17

yersinia pestis (g proteobact - entero)
get enlarged lymph nodes
detah 3-5 days

Question 18

g proteo - vibrionales

Answer 18

g neg, fac anaerobes

cholera
-diarrhea, water/food borne
-use die from dehyd
-john snow (epidemiology - study of numbers w disease)
-bact enters cell, efflux Cl which go outside and release water to balance (exotoxin secreted into env which causes symptoms)

Question 19

delta proteo

Answer 19

chemoorganotrophs
anaerobic sulfur or sulfate reducing bact (imp for S cycle)

bdellovibrionales - can act as predator

Question 20

epsilon proteo

Answer 20

g neg
2 pathogens = camplybacter and helicobacter (can cause alcers)

Question 21

Spirochaetes

Answer 21

g neg
chemoheterotrophs
anearob/ fac anaer, or aerobes
causes lyme disease and syphilis

move w flagella, anchored and tucked in bw mems (rotates like corkscrew)
–can evade IS bc flagella protected by sheath (outer sheath foes not have LPS which is usu target)

Question 22

more ab stds/syphilis

Answer 22

spirochaete
no tca or ox phos t/f imports ATP
intracellular parasite affecting CNS and cardiovasc syst
penicillan to treat
Tuskgee exp

Question 23

bacteriodetes

Answer 23

class bacteroides = imp
-common in gut
-anaer chemoheterotroph
-g neg, non spore forming
-dont reduce S

Question 24

Chlamydiae

Answer 24

obligate intracellular parasite (need host to survive bc have small genome now cant do glycolysis/make atp)
g neg
non motile cocci
has 2 dif life forms (elemental body = smaller, denser, met inert inside host; once in cell, stim’d and do binary fission)