MIBO 3500 EXAM 3 QUESTIONS & ANSWERS
Original Microbial Taxonomy - Answers -- traditional microbial taxonomy was NOT
rooted in evolutionary relatedness
-naming referenced the diseases they cause or processes they performed
polyphasic taxonmy - Answers --current method for microbial taxonomy
-consists on genotype, phenotype, and evolutionary (rRNA)
3 major bacterial groups - Answers -1. deep branching thermophiles
2. cyanobacteria
3. gram-positive bacteria
Deep branching thermophiles - Answers --diverged the earliest from ancestral archaea
and eukaryotes
-fastest doubling rates of all bacteria
-high mutation rate, gram negative
Phylum Aquificae - Answers --member of deep branching thermophiles
-"water maker"
-oxidize hydrogen gas with oxygen to make water
-ETHER linked membrane lipids
Thermocrinis ruber - Answers --member of deep branching thermophiles
-in lab--> media grows as a rod
-in natural environment-->streams, grow long thin intertwined filaments
-82-88 C temperature preference
**media dependent morphology
-found in Yellowstone's Octopus stream
Phylum Thermotogae - Answers --deep branching thermophile
-"toga"
- loosely bound sheath( absence of classical outer membrane)
-mosaic genomes(bacterial-archaeal)
Thermotoga maritima - Answers --One of the highest recorded growth temperatures
(90˚C)
-During growth "sheath" extends from the poles.
-Outer envelope "grows"
-Cytoplasmic growth "stalls"
Cyanobacteria - Answers --largest, most diverse group of photosynthetic bacteria
-oxygenic= can make oxygen
-thick peptidoglycan layer
, -appear green due to blue and red absorption by chlorophylls
Cyanobacterial Mutualism - Answers --share many kinds of mutualistic associations
-participate in multilayered microbial mats
Cyanobacteria shapes - Answers –
-filamentous (plate like cells)
-colonial ( surrounded by mucus, grow as single cells, doublets, or quartets)
ex: Chroococcus
Heterocysts - Answers --specialized cells used for nitrogen fixation in cyanobacteria
-produced when organism is nitrogen deprived
-thick heterocyst wall prevents O2 diffusion into heterocyst which would inactivate
nitrogenase
heterocyst formation - Answers --filamentous cyanobacteria forms chains by cell
division
-when nitrogen NOT present, heterocyst incorporated into chain and able to fix N2
Nostoc - Answers --genus of cyanobacteria that produces heterocyst
Phylum Cyanobacteria - Answers --may have thylakoids(photosynthesis)
-may have carboxysomes(fix CO2)
Synechococcus elongatus - Answers --example of cyanobacterial species that also
prefers warm stream water ( Yellowstone Octopus Spring)
Group Gram positives bacteria - Answers --comprised of two distinct phylogenetic
branches
1. phylum firmicutes (Low GC species)
2. Phylum actinobacteria (high GC species)
Phylum Firmicutes - Answers --low GC
-many form endospores
Original Microbial Taxonomy - Answers -- traditional microbial taxonomy was NOT
rooted in evolutionary relatedness
-naming referenced the diseases they cause or processes they performed
polyphasic taxonmy - Answers --current method for microbial taxonomy
-consists on genotype, phenotype, and evolutionary (rRNA)
3 major bacterial groups - Answers -1. deep branching thermophiles
2. cyanobacteria
3. gram-positive bacteria
Deep branching thermophiles - Answers --diverged the earliest from ancestral archaea
and eukaryotes
-fastest doubling rates of all bacteria
-high mutation rate, gram negative
Phylum Aquificae - Answers --member of deep branching thermophiles
-"water maker"
-oxidize hydrogen gas with oxygen to make water
-ETHER linked membrane lipids
Thermocrinis ruber - Answers --member of deep branching thermophiles
-in lab--> media grows as a rod
-in natural environment-->streams, grow long thin intertwined filaments
-82-88 C temperature preference
**media dependent morphology
-found in Yellowstone's Octopus stream
Phylum Thermotogae - Answers --deep branching thermophile
-"toga"
- loosely bound sheath( absence of classical outer membrane)
-mosaic genomes(bacterial-archaeal)
Thermotoga maritima - Answers --One of the highest recorded growth temperatures
(90˚C)
-During growth "sheath" extends from the poles.
-Outer envelope "grows"
-Cytoplasmic growth "stalls"
Cyanobacteria - Answers --largest, most diverse group of photosynthetic bacteria
-oxygenic= can make oxygen
-thick peptidoglycan layer
, -appear green due to blue and red absorption by chlorophylls
Cyanobacterial Mutualism - Answers --share many kinds of mutualistic associations
-participate in multilayered microbial mats
Cyanobacteria shapes - Answers –
-filamentous (plate like cells)
-colonial ( surrounded by mucus, grow as single cells, doublets, or quartets)
ex: Chroococcus
Heterocysts - Answers --specialized cells used for nitrogen fixation in cyanobacteria
-produced when organism is nitrogen deprived
-thick heterocyst wall prevents O2 diffusion into heterocyst which would inactivate
nitrogenase
heterocyst formation - Answers --filamentous cyanobacteria forms chains by cell
division
-when nitrogen NOT present, heterocyst incorporated into chain and able to fix N2
Nostoc - Answers --genus of cyanobacteria that produces heterocyst
Phylum Cyanobacteria - Answers --may have thylakoids(photosynthesis)
-may have carboxysomes(fix CO2)
Synechococcus elongatus - Answers --example of cyanobacterial species that also
prefers warm stream water ( Yellowstone Octopus Spring)
Group Gram positives bacteria - Answers --comprised of two distinct phylogenetic
branches
1. phylum firmicutes (Low GC species)
2. Phylum actinobacteria (high GC species)
Phylum Firmicutes - Answers --low GC
-many form endospores
