Lecture 5A - Domain Bacteria: Taxonomy, Classification and Cell Structure Flashcards
1
Q
different approaches to bacterial classification
A
- numerical approach
- phylogenetic approach
- polyphasic approach
2
Q
three subtopics of taxonomy
A
- classification
- nomenclature
- identification
3
Q
ordering of organisms into delineated groups based on similarities
A
classification
4
Q
naming these groups according to bacterial code
A
nomenclature
5
Q
verifying whether an unknown belongs to one of the groups defied in classficiation and named in nomenclature for which a combination of methods is usually applied
A
identification
6
Q
hierarchical grouping of prokaryotic taxonomy
A
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
Subspecies
7
Q
why is bacterial taxonomy important
A
helps classify and arrange bewildering diversity of bacteria into groups or taxa on the basis of their mutual similarity or evolutionary relatedness
8
Q
- method of classifying organisms with the help of numerical methods
- each character is given equal weightage in creating new taxa
A
numerical approach
9
Q
ideal means of identifying and classifying bacteria would be to compare each gene sequence in a given strain with the gene sequences for every known species
A
phylogenetic approach
10
Q
collectively these genotypic, chemotaxonomic and phenotypic methods for determining taxonomic position of microbes
A
polyphasic approach
11
Q
committee of appointed representatives from the national microbiological societies and co-opted members that oversees the nomenclature of prokaryotes, determines the rules by which prokaryotes are named
A
International Committee on Systematics of Prokaryotes (ICSP)
12
Q
how should a bacterial species be named
A
binary combination:
genus
single specific epithet
13
Q
prokaryote nomenclature, is used to name prokaryotic phyla that are well characterized but yet-uncultured
A
Candidatus
14
Q
- biggest group
- Gram-negative
- mythical Greek god, Proteus, who could assume many shapes
A
Phylum Proteobacteria
15
Q
Proteobacteria name
A
from Greek god, Proteus, who could assume many shapes
16
Q
Five subgroups of Phylum Proteobacteria
A
- alpha Proteobacteria
- beta Proteobacteria
- gamma Proteobacteria
- delta Proteobacteria
- epsilon Proteobacteria
17
Q
- include most proteobacteria capable of growth at very low nutrient levles
- some have unusual morphology
- includes agriculturally important bacteria
A
alpha Proteobacteria
18
Q
most extreme environment
A
air/atmosphere
19
Q
least extreme environment
A
soil
20
Q
assume many shapes
A
pleomorphic
21
Q
alpha Proteobacteria includes what
A
agriculturally important bacteria
22
Q
- usually found in sewage and decomposition areas
- containas Neisseria gonorrhoeae which causes gonorrhea and Neisseria meningitidis cause of meningitis
A
beta Proteobacteria
23
Q
most of beta Proteobacteria are what
A
- anerobic
- some are facultative anaerobic
24
Q
- largest Proteobacteria subgroup
- many are beneficial symbionts of the gut
- some human pathogens
- few oxidize sulfur compounds
- contains Pseudomonas and Enterobacteriales
A
gamma Proteobacteria
25
gamma Proteobacteria microorgansms
Pseudomonas
Enterobacteriales
26
Psuedomonas are what
- opportunistic pathogens
- metabolically diverse
27
Enterobacteriales inhabit where
intestinal tracts of humans and other animals
28
Genera under Enterobacteriales
1. Enterobacter
2. Escherichia**, e.g E. col
3. Klebsiella
4. Proteus
5. Salmonella**
6. Serratia
7. Shigella
29
causes disease if immune system is low
Enterobacter
30
- include bacteria that attack other bacteria
- include sulfure reducing bacteria
delta Proteobacteria
31
Anaerobic delta Proteobacteria
Desulfovibrio
32
two types of aerobic delta Proteobacteria
1. predator
2. gliding
33
aerobic delta Proteobacteria:
predator
_Bdellovibrio_
34
aerobic delta Proteobacteria:
gliding
_Myocococcus_
35
- slender and helical
- include Helicobacter pylori
epsilon Proteobacteria
36
Two types of epsilon Proteobacteria
1. polar flagella
2. Peritrichous flagella
37
epsilon Proteobacteria:
polar flagella
Campylobacter
38
Campylobacter
threat in food industry
39
epsilon Proteobacteria:
Peritrichous flagella
Helicobacter
40
causes peptic ulcers
Helicobacter pylori
41
- some species are photoautotrophic but some are symbionts of plants and animals
- others are pathogens
- eukaryotic mitochondria are thought to be derived from bacteria in this group
alpha Proteobacteria
42
representative organisms in alpha Proteobacteria
1. Rhizobium
2. Rickettsia
43
nitrogen fixing endosymbiont associated with the roots of legumes
Rhizobium
44
obligate intracellular parasite that causes typhus and Rocky Mountain Spotted Fever
Rickettsia
45
caused by Vitamin C deficiency
rickets
46
- diverse
- some species play an important role in the nitrogen cycle
beta Proteobacteria
47
representative organisms in beta Proteobacteria
1. _Nitrosomas_
2. _Spirillum_ _minus_
48
oxidize ammonia into nitrite
Nitrosomas
49
causes rat-bite fever
_Spirillum_ _minus_
50
- many are beneficial symbionts that populate the human gut
- others are familiar human pathogens
- some species oxidize sulfur compounds
gamma Proteobacteria
51
representative organisms of gamma Proteobacteria
1. _Escherichia_ _coli_
2. _Salmonella_
3. _Yersinia_ _pestis_
4. _Pseudomonas_ _aeruginosa_
5. _Vibrio_ _cholera_
6. _Chromatium_
52
normally beneficial microbe of the human gut, but some strains cause disease
Escherichia coli
53
certain strains cause food poisoning or typhoid fever
Salmonella
54
causative agent of Bubonic plague
**Yersinia pestis
55
causes lung infections
_Pseudomonas_ _aeruginosa_
56
causative agent of cholera
_Vibrio_ _cholera_
57
- sulfur-producing
- oxidize sulfur, producing H2S
_Chromatium_
58
- some species generate a spore-forming fruiting body in adverse conditions
- others reduce sulfate and sulfur
delta Proteobacteria
59
representative organisms of delta Proteobacteria
1. _Myxobacteria_
2. _Desulfovibrio_ _vulgaris_
60
generate spore-forming fruiting bodies in adverse conditions
_Myxobacteria_
61
- anaerobic
- sulfate-reducing bacterium
_Desulfovibrio_ _vulgaris_
62
- many species inhabit the digestive tract of animals as symbionts or pathogens
- bacteria from this gruop have been found in deep-sea hydrothermal vents and cold seep habitats
epsilon Proteobacteria
63
representative organisms of epsilon Proteobacteria
1. _Campylobacter_
2. _Helicobacter_ _pylori_
64
causes blood poisoning and intestinal inflammation
_Campylobacter_
65
causes stomach ulcers
_Helicobacter_ _pylori_
66
Four other Phylum of bacteria
1. Chlamydias
2. Spirochetes
3. Cyanobacteria
4. Gram-positive bacteria
67
- all members of this group are obligate intracellular parasites of animal cells
- cell walls lack peptidoglycan
chlamydias
68
all members of the _Chlamydia_ are what
obligate intracellular parasites
69
representative organisms of chlamydias
_Chlamydia_ _trachomatis_
70
common sexually transmitted disease that can lead to blindness
_Chlamydia_ _trachomatis_
71
- most members, which has spiral-shaped cells, are free-living anaerobes, but some are pathogenic
- flagella run lengthwise in the periplasmic space between the inner and outer membrane
spirochetes
72
representative organisms of spirochetes
1. _Treponema_ _pallidum_
2. _Borrelia_ _burgdorferi_
73
causative agent of syphilis
_Treponema_ _pallidum_
74
causative agent of Lyme disease
_Borrelia_ _burgdorferi_
75
- soil-dwelling members of this subgroup decompose organic matter
- some species cause disease
- have thick cell wall and lack outer membrane
Gram-positive bacteria
76
representative organisms of Gram-positive bacteria
1. _Bacillus_ _anthracis_
2. _Clostridium_ _botulinum_
3. _Clostridium_ _difficile_
4. _Streptomyces_
5. _Mycoplasmas_
77
causes anthrax
_Bacillus_ _anthracis_
78
causes Botulism
_Clostridium_ _botulinum_
79
botulism
caused by a toxin that attacks the body's nerves
80
causes diarrhea during antibiotic therapy
_Clostridium_ _difficile_
81
many antibiotics, including streptomycin, are derived from these bacteria
_Streptomyces_
82
- tiny bacteria, smallest known, lack cell wall
- some are free-living, some pathogenic
_Mycoplasmas_
83
oxygenic photoautotrophs
Cyanobacteria
84
anoxygenic photoautotrophs
Chlorobi
85
possess axial filament
Spirochetes
86
Intracellular parasites
_Chlamydia_
87
- Gram-positive and Low G+C ratio
- DNA is made up of base pairs
- includes important endospore forming bacteria
Gram +: Firmicutes
88
- Gram-positive and High G+C ratio
- take on many shapes/forms (pleomorphic)
Gram +: Actinobacteria
89
reproductive structures that enable filamentous fungi to produce and disseminate large numbers of asexual spores
Conidiophores
90
causes TB and leprosy
_Mycobacterium_
90
PCR indicates up to how many bacteria
10,000 bacteria/gm of soil
91
why are many bacteria not identified or characterized
1. haven't been cultured
2. need special nutrients
3. part of complex food chains requiring products of other bacteria
4. need to be cultured to understand metabolism and ecological role
92
- also known as blue-greeb algae
- obtain energy through photosynthesis
- ubiquitous
- eukaryotic chloroplasts are thought to be derived from bacteria in this group
Cyanobacteria
93
Representative organisms of Cyanobacteria
_Prochlorococcus_
94
- Believed to be the most abundant photosynthetic organism on earth
- responsible for generating half the world's oxygen
_Prochlorococcus_
