Bacterial Diversity Flashcards
1
Q
Modified T/F
Most of the Earth’s biodiversity is prokaryotic.
A
True
2
Q
List & Differentiate
Two kinds of Diversity
A
Structural diversity
- allows prokaryotes to adapt to specific environments
- Ex. psychrophiles and thermophiles have molecular structures to thrive in extreme temperatures (adaptations in cell membrane composition and specialized proteins)
Metabolic Diversity
- how they get energy and nutrients from their environment
3
Q
List
Domain Bacteria
12
A
- Proteobacteria - P
- Gram-Positive Bacteria - group
- Bacteroidetes - P
- Cyanobacteria - P
- Chlamydiae - P
- Planctomycetes - P
- The green sulfur bacteria - F
- Spirochetes - P
- Deinococcus-Thermus - P
- Green Non-Sulfur Bacteria - C
- Thermotogae - P
- Aquificae - P
4
Q
- Phylum
- Has no defining characteristic
- G-
A
Proteobacteria
5
Q
List
Classes of Proteobacteria
Bonus: in order of size
6
A
- Gamma-
- Alpha-
- Beta-
- Delta- (less diverse)
- Epsilon- (less diverse)
- Zeta- (only 1 species)
6
Q
2nd largest class of Proteobacteria
A
Alphaproteobacteria
7
Q
List
Representative genera of Alphaproteobacteria
3
A
- Rhizobium
- Agrobacterium
- Rickettsia
8
Q
Identify
- plant symbionts
- live in root nodules and participate in nitrogen fixation
- Genera of Alphaproteobacteria
A
Rhizobium
9
Q
Identify
- causes crown gall disease in plants
- infects plants by injecting a special plasmid into host cells
- biotechnologists used this bacterium as a vector in recombinant DNA technology
- Genera of Alphaproteobacteria
A
Agrobacterium
10
Q
Identify
- obligate intracellular parasites
- transmitted by ticks and mites
- Genera of Alphaproteobacteria
A
Rickettsia
11
Q
3rd largest class of Proteobacteria
A
Betaproteobacteria
12
Q
List
Representative genera of Betaproteobacteria
3
A
- Burkholderia
- Neisseria
- Chromobacterium
13
Q
- genera of Betaproteobacteria
- soil bacterium
- becoming an opportunistic pathogen in nosocomial/hospital-acquired infections
A
Burkholderia
14
Q
genera of Betaproteobacteria
causative agent of diseases like gonorrhea
A
Neisseria
15
Q
genera of Betaproteobacteria
soil-dwelling bacterium
produces a purple pigment called violacein
Bonus: Some years ago, a thesis pair was able to isolate and identify this from soil samples in SEC A.
A
Chromobacterium
16
Q
Largest & most diverse class of Proteobacteria
A
Gammaproteobacteria
17
Q
List
Representative genera of Gammaproteobacteria
4
A
- Escherichia (E. coli)
- Salmonella
- Pseudomonas
- Vibrio (V. cholerae)
18
Q
genera of Gammaproteobacteria
enteric bacterium
A
Escherichia (E. coli)
19
Q
genera of Gammaproteobacteria
causes salmonellosis
A
Salmonella
20
Q
- genera of Gammaproteobacteria
- can become opportunistic pathogens in immunocompromised individuals
A
Pseudomonas
21
Q
- genera of Gammaproteobacteria
- pathogenic bacterium that causes cholera
- some species are bioluminescent
- give genera & species
A
Vibrio (V. cholerae)
22
Q
Bioluminescent species of Vibrio
A
V. fischeri, V. harveyi
23
Q
- genus of sulfate reducers
- isolated from marine sediments and nutrient- rich anoxic environment
- Representative genus of Deltaproteobacteria
A
Desulfovibrio
24
Q
- Genus/species that can infect the stomach lining and cause peptic ulcer
- Representative genus of Epsilonproteobacteria
- give genus & species
A
Helicobacter (H. pylori)
25
What are the common characteristics of the G+ bacteria group?
Same phylogeny & cell wall structure
26
# List
Phyla of G+ Bacteria
| 3
1. Firmicutes / low-GC G+ bacteria
1. Tenericutes
1. Actinobacteria
27
* Phyla of G+ Bacteria
* low GC content of their DNA
Firmicutes / low-GC G+ bacteria
28
# List
Examples of Firmicutes
| 3
1. *Lactobacillus*
1. *Staphylococcus*
1. *Clostridium*
29
Ex. of Firmicutes
lactic acid bacteria
in yogurt
*Lactobacillus*
30
* Ex. of Firmicutes
* common skin dwelling bacterium
* Some strains became resistant to antibiotics
*Staphylococcus*
31
Antibiotic resistant strain of Staphylococcus
methicillin-resistant *S. aureus* / MRSA
32
* Ex. of Firmicutes
* endospore-forming pathogen
* anaerobic foodborne pathoen
* in improperly processed canned goods (inflated)
* Give genus & species
*Clostridium
C. botulinum*
33
* Phyla of G+ Bacteria
* cell wall-less bacteria
* phylogenetically related to other G+ bacteria (but don’t stain G+ bc of no cell wall)
Tenericutes
34
# List
Examples of Tenericutes
| 2
1. *Mycoplasma*
1. *Spiroplasma*
35
* Examples of Tenericutes
* symbionts of animal and plant hosts
*Mycoplasma*
36
Examples of Tenericutes
helical bacterium with screwing motility
*Spiroplasma*
37
* Phyla of G+ Bacteria
* High GC
* Has both disease-causing & disease-fighting bacteria
Actinobacteria
38
# List
Examples of Actinobacteria
| 2
1. *Mycobacterium*
1. *Streptomyces*
39
* Example of Actinobacteria
* causes tuberculosis
* Give genus + species
*Mycobacterium tuberculosis*
40
Bonus: How can you tell through an x-ray that a person has tuberculosis?
One lung has a higher opacity than the other
41
* Example of Actinobacteria
* soil-dwelling filamentous bacteria
* responsible for producing more than 2/3 of clinically useful antibiotics of natural origin
*Streptomyces*
42
* phylum of G- nonsporulating rods
* Saccharolytic
* makes them a major component in the gut microbiota of humans & other mammals
Bacteroidetes
43
# Define
Saccharolytic
can break down complex polysaccharides
44
Examples of Actinobacteria
| 2
*Bacteroides* and *Prevotella*
45
Where can you find *Bacteroides* and *Prevotella*?
Bacteria in the colon
46
How does the host’s diet affect the prominence of *Bacteroides* vs the prominence of *Prevotella*?
↑ plants = ↑ Prevotella
↑ meat and fats = ↑ Bacteroides
47
* Phylum of photosynthetic bacteria
* played a huge role in the evolution of the planet
* first oxygenic photoautotrophs to evolve on Earth
* turned the planet’s atmosphere from anoxic to an oxygen-rich environment
* allowed aerobic organisms to thrive and evolve → current diverse aerobic life
* Diff morphologies
Cyanobacteria
48
# List
Examples of Cyanobacteria
| 4
1. *Synecococchus*
1. *Oscillatoria*
1. *Microcystis*
1. *Anabaena*
49
unicellular marine cyanobacterium
*Synecococchus*
50
freshwater genus, filamentous
Cyanobacteria
*Oscillatoria*
51
* freshwater genus under Cyanobacteria
* Made of colonial cells that produce toxic algal blooms
*Microcystis*
52
* nitrogen fixer
* heterocystous morphology (cells that compose the chain of the organism have varying sizes)
* Examples of Cyanobacteria
*Anabaena*
53
* phylum of obligate intracellular parasites of eukaryotic cells
* cause of respiratory and sexually transmitted diseases in humans
Chlamydiae
54
How do Chlamydiae infect hosts?
invade healthy cells where they replicate and eventually destroy their host cells
55
Examples of Chlamydiae
| 2
How are they transmitted?
*Chlamydia pneumoniae*
* a respiratory pathogen
*Chlamydia trachomatis*
* a sexually transmitted pathogen
56
* phylum of aquatic bacteria
* presence of a stalk and asexual reproduction via budding
* many possess an S-layer (characteristic of archaea cells)
* may have intracellular compartments like organelles of eukaryotic cells.
Planctomycetes
57
* possess a protein stalk for attachment to substratum
* Representative genus of Planctomycetes
*Planctomyces*
58
family of obligate anaerobes
thrive as anoxygenic photolithotrophs
Green Sulfur Bacteria
59
* genus that photo-oxidizes sulfur using chlorosomes
* Green Sulfur Bacteria
*Chlorobium*
60
# Define
chlorosomes
light-harvesting complexes
61
* phylum of helically shaped bacteria
* **axial filaments** that run along the length of the cell within the periplasmic space
Spirochetes
62
Examples of Spirochetes
What diseases do they cause?
| 2
1. *Treponema*: causes syphilis
1. *Leptospira*: causes leptospirosis.
63
* phylum composed of aerobic chemoorganotrophs.
* structurally G- (have an outer layer), but stain as G+ (thick peptidoglycan layer)
Deinococcus-Thermus
64
* extremely resistant to radiation
* due to highly-efficient DNA repair enzymes
* Example of Deinococcus-Thermus
Deinococcus
65
* thermophilic bacterium
* source of the Taq polymerase (replicates DNA in PCR)
* Example of Deinococcus-Thermus
* Species + genus
Thermus (*Thermus aquaticus*)
66
* class of filamentous anoxygenic phototrophs
* grow best as photoheterotrophs using simple carbon sources as e- donors
Green Non-Sulfur Bacteria
67
Example of Green Non-Sulfur Bacteria
* Where is it found?
* What is it associated with?
***Chloroflexus***
* commonly found in the lower layers of microbial mats near hot springs
* usu. associated with cyanobacteria found in the upper layers.
68
hyperthermophiles w/ a toga that forms around the cell
Thermotogae
69
# Define
toga
* a sheath-like envelope
* in Thermotogae
70
What is the representative genus of Thermotogae?
Where can it be found?
*Thermotoga*
thrives in hot springs and hydrothermal vents on the ocean floor
71
* obligately chemolithotrophic and autotrophic hyperthermophiles
* Phylum
Aquificae
72
* most thermophilic of all Bacteria
* can grow in low oxygen environments at temperatures up to 95ºC
* microaerophilic
* representative genus of Aquificae
Aquifex
73
# List
Archaea
| 5
1. Euryarchaeota
1. Thaumarchaeota
1. Nanoarchaeota
1. Korarchaeota
1. Crenarchaeota
74
# List
Members of Euryarchaeota
| 3
1. Extreme halophiles
1. Methanogens
1. Hyperthermophiles
75
* inhabits environments with high salt concentration (solar salt evaporation ponds, salt lakes, surfaces of heavily salted foods)
* requires environmental salt concentration >9%
* most species require 12-23% salt
* concentration (some up to 32%)
* Ex: *Halobacterium*, *Natronobacterium*
Extreme halophiles
76
What is the **required** environmental salt concentration for extreme halophiles?
What is the **actual** range of salt concentration for most species of extreme halophiles?
> 9%, 12-23% (some up to 32%)
77
* produce methane gas through methanogenesis
* play important roles in anoxic habitats [aquatic sediments, wastewater treatment plants, animal guts (cows, termites)]
* Ex.: Methanosarcina, Methanobrevibacter
Methanogens
78
thermophilic and extremely acidophilic archaea
Ex.:
* Thermoplasma and Ferroplasma: lack cell walls
* Picrophilus: most acidophilic of all known microbes; can grow in pH < 0.
Thermoplasmatales
79
List
Kinds of Hyperthermophiles
| 2
1. Thermococcales
1. Archaeoglobales
80
Hyperthermophiles
obligately anaerobic chemoorganotrophs
Thermococcales
81
hyperthermophilic
often isolated from hydrothermal vents
Archaeoglobales
82
nitrifying archaea in marine environments and soil
Ex. Nitrosopumilus and Nitrososphaera
* Used to be Crenarchaeota
* but genome sequence analysis of Nitrosopumilus maritimus showed that it’s a unique phylum
Thaumarchaeota
83
* represented by one species only
* one of the smallest cellular organisms
* smallest genome in Archaea (0.49 mega-base pairs / 490,000 base pairs in DNA)
* Archaeal surface symbiont to Ignicoccus hospitalis.
* [species] is often described as “riding the hospitable fireball” (like fire around I. hospitalis)
| Give phylum & species
Phylum Nanoarchaeota
*Nanoarchaeum equitans*
84
* represented by one species only
* Hyperthermophilic
* obligately anaerobic chemoorganotroph
* yet to be grown in a pure culture
* only characterized through metagenomic studies of enrichment cultures.
* highly reliant on other species in its environment.
| Give phylum & species
Phylum Korarchaeota
*Korarchaeum cryptofilum*
85
mostly hyperthermophilic members
some species even growing optimally above the boiling point of water
chemolithotrophic autotrophs
primary producers in high temperature environments.
Crenarchaeota
86
# List
Kinds of Crenarchaeotes
| 2
1. Terrestrial Volcanic Crenarchaeotes
1. Submarine Volcanic Crenarchaeote
87
* can often be found in sulfur-rich hot springs
* also in neutral boiling springs and acidic iron-rich springs.
* Ex.: Sulfolobus, Acidianus, Thermoproteus, Pyrobaculum
Terrestrial Volcanic Crenarchaeotes
