Chap 11 Flashcards
The Prokaryotes: Domains Bacteria and Archaea (321 cards)
1
Q
Prokaryotes in Bergey’s manual are grouped into two domains
A
Archaea & Bacteria
2
Q
Domain of prokaryotic cells lacking in peptidoglycan
A
archaea
3
Q
bacteria are also commonly distinguished by gram staining
A
gram positive or gram negative
4
Q
proteobacteria characteristics
A
1.Gram-negative,
2.chemoheterotrophic bacteria that posses a
3.signature rRNA sequence
5
Q
proteobacteria are thought to have arised from
A
a common photosynthetic ancestor
6
Q
Largest taxonomic group of bacteria
A
proteobacteria
7
Q
Few proteobacteria are
A
photosynthetic, other capacities have replaced this characteristic
8
Q
The phylogenetic relationship between proteobacteria is based upon
A
rRNA studies
9
Q
The name proteobacteria comes from
A
Greek god Proteus, who could take many shapes
10
Q
Proteobacteria are designated into five classes
A
- alphaproteobacteria
- beta
- gamma
- delta
- epsilon
11
Q
Alphaproteobacteria capable of growth with very low levels of ______
A
nutrients
12
Q
prosthecae
A
unusual stalks or buds that grow out of alphaproteobacteria
13
Q
prostheca
A
a stalk or bud protruding from a prokaryotic cell
14
Q
Include agriculturally important bacteria capable of nitrogen fixation
A
alphaproteobacteria
15
Q
Pelagibacter Ubique
A
most abundant living organism in the oceans on the basis of weight.
16
Q
Thought to have an important role in the earth’s carbon cycle
A
P. ubique
17
Q
P. Ubique has a small size and small genome, which allows it to
A
survive in low-nutrient environment
18
Q
size of P. ubique
A
0.3 micrometers in diameter
19
Q
Which bacteria have the smallest genomes?
A
bacteria in symbiotic relationships because they have lower metabolic requirements
20
Q
What has a smaller genome than P. ubique?
A
several mycoplasmas
21
Q
has only 1354 genes
A
P. Ubique
22
Q
first member of SAR 11 group to be successfully cultivated
A
P. ubique
23
Q
Azospirilum
A
soil bacterium; grows closely associated to roots, especially in tropical grasses. Uses nutrients excreted from the plants to fix nitrogen from atmosphere.
24
Q
azo-
A
nitrogen fixing
25
azo- comes from
without life, nitrogen associated with no life
26
Acetobacteraceae & Gluconobacter
industrially important 1. aerobic organisms that
2.convert ethanol into acetic acid (vinegar).
27
Granulibacter
emerging; found in patients with chronic granulomatous disease.
28
In the first edition of Bergey’s Manual, the genera Rickettsia, Coxiella, and Chlamydia were grouped closely because
all obligate intracellular parasites—that is, they reproduce only within a mammalian cell
29
In the second edition they are now widely separated.
Rickettsias, chlamydias, and viruses
30
Contain a single type of nucleic acid, either DNA or RNA
viruses
31
Contain a protein coat (sometimes itself enclosed by an envelope of lipids, proteins, and carbohydrates) that surrounds the nucleic acid.
viruses
32
Multiply inside living cells by using the synthesizing machinery of the cell
viruses
33
Cause the synthesis of specialized structures that can transfer the viral nucleic acid to other cells.
viruses
34
Rickettsias gram negative or gram positive?
gram-negative
35
One distinguishing feature of most rickettsias
transmitted to humans by insect and tick bites
36
Rickettsia enter their host cell by
Inducing phagocytosis. They quickly enter the cytoplasm of the cell and begin reproducing by binary fission
37
Rickettsias can usually be cultivated artificially in
cell culture or chick embryos
38
are responsible for a number of diseases known as the spotted fever group.
Rickettsias
39
epidemic typhus, caused by
Rickettsia prowazekii
40
Epidemic typhus is transmitted by
transmitted by lice
41
endemic murine typhus, caused by
R. typhi
42
endemic murine typhus, transmitted by
rat fleas
43
Rocky Mountain spotted fever, caused by
R. rickettsii, transmitted by ticks
44
In humans, rickettsial infections damage
The permeability of blood capillaries, which results in a characteristic spotted rash.
45
Ehrlichia
1.gram-negative, 2.rickettsia-like bacteria that
3. live obligately within white blood cells
46
Ehrlichia species are transmitted by
ticks to humans
47
cause ehrlichiosis, a sometimes fatal disease
Ehrlichia
48
Caulobacter and Hyphomicrobium found in
low-nutrient aquatic environments, Lakes
49
Have stalks that anchor the organisms to surfaces
Caulobacter and Hyphomicrobium
50
Waht is the function of the stalk in Caulobacter and Hyphomicrobium?
Increases nutrient uptake
51
How does the stalk increase nutrient uptake?
-exposed to changing flow of water, increases surface area,
-can use host excretions as nutrients
52
When does the stalk grow?
When the nutrient concentration is exceptionally low, to pick up more food
53
Budding bacteria don’t divide by
binary fission into two identical cells
54
What happens during the budding process?
The parent cell retains its identity while the bud increases in size until it separates as a complete new cell.
55
Hyphomicrobium found in
in low-nutrient aquatic environments
56
Caulobacter and Hyphomicrobium reproduce by
budding rather than binary fission
57
Both Caulobacter and Hyphomicrobium produce prominent
prosthecae
58
Rhizobium, Bradyrhizobium infect
roots of leguminous plants, such as beans, peas, or clover
59
common name of Rhizobium, Bradyrhizobium
rhizobia
60
presence of rhizobia in the roots leads to
formulation of nodules;
61
Rhizobia and plant form a symbiotic relationship that results in
fixation of nitrogen from the air so it can be used by the plant
62
Agrobacterium can invade
plants
63
can invade plants but these bacteria do not induce root nodules or fix nitrogen
Agrobacterium
64
Agrobacterium tumefaciens causes a disease called
crown gall
65
Plant crown
Area of plant where roots and stem merge
66
How does crown gall occur?
A. tumefaciens inserts a plasmid containing bacterial genetic information into the plant’s chromosomal DNA
67
Plasmids
most common vector that scientists use to carry new genes into a plant cell
68
Why are plasmids the most common vector that scientists use to carry new genes into a plant cell?
Thick wall of plants is hard to penetrate
69
Genus __________ has several members that are human pathogens
Bartonella
70
Bartonella henselae
1.gram-negative bacillus that
2.causes cat-scratch disease
71
Brucella
obligate parasites of mammals, cause of brucellosis
72
small nonmotile coccobacilli, cause brucellosis
Brucella
73
Brucella can survive
phagocytosis
74
Nitrobacter and Nitrosomonas are important to
environment and agriculture; nitrifying bacteria
75
Obligate parasite of mammals; survives phagocytosis
Causes brucellosis
Brucella
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Nitrobacter and Nitrosomonas are chemoautotrophic, meaning
use inorganic chemicals as energy source; CO2 as carbon source
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Nitrosomonas equation
NH4 ---> NO2-
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Nitrobacter equation
NO2- ---> NO3-
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Wolbachia
Endosymbiont of insects
Affects reproduction of insects
80
The energy sources of the genera Nitrobacter and Nitrosomonas (the latter is a member of the betaproteobacteria) are
reduced nitrogenous compounds
81
Nitrate is important to agriculture;
it’s a nitrogen form that’s highly mobile in soil and therefore likely to be encountered and used by plants.
82
most common infectious bacterial genus in the world
Wolbachia
83
Wolbachia live only inside the cells of
their hosts
84
hosts of wolbachia are usually
Insects
85
escapes detection by the usual culture methods.
Wolbachia
86
interferes with reproduction and egg development in infected insects.
Wolbachia
87
Wolbachia-infected male Aedes aegypti mosquitoes are being released in several places including Brazil, Florida, California, and southeast Asia to
prevent the spread of Zika, chikungunya, and dengue viruses
88
The Betaproteobacteria
1. Acidithiobacillus
2. Spirillum
3. Sphaerotilus
89
Found in freshwater
Move via flagella
Spirirlum
90
Acidithiobacillus
1.Chemoautotrophic;
2.oxidize sulfur to sulfates:
H2S ---> SO4 2-
91
Sphaerotilus function
Form sheaths to aid in protection and nutrient gathering
92
The betaproteobacteria often use nutrient substances that diffuse away from
areas of anaerobic decomposition of organic matter, such as hydrogen gas, ammonia, and methane. Several important pathogenic bacteria are found in this group.
93
sulfur-oxidizing bacteria are important in the sulfur cycle
Acidithiobacillus
94
chemoautotrophic bacteria capable of obtaining energy by oxidizing the reduced forms of sulfur, such as hydrogen sulfide (H2S), or elemental sulfur (S0), into sulfates (SO42−).
Acidithiobacillus
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________ bacteria are motile by conventional polar flagella
Spirillum
96
Relatively large, gram-negative, aerobic bacteria.
Spirilla
97
Sphaerotilus gram negative or gram positive?
1. gram-negative
98
Sheaths aid in
protection and nutrient accumulation
99
Sphaerotilus natans contributes to
bulking in sewage
100
can eventually swim free of the sheath.
Sphaerotilus
101
Burkholderia motile by
single polar flagellum or tuft of flagella
102
Burkholderia cepacia aerobic vs anaerobic
aerobic,
103
nutritional spectrum of Burkholderia cepacia
capable of degrading more than 100 different organic molecules.
104
The large nutritional spectrum of burkholderia is a problem because
bacteria can grow in diinfectant solutions. Contamination of equipment and drugs in hospitals
105
Why is burkholderia a problem for people with genetic lung disease cystic fibrosis,?
it metabolizes accumulated respiratory secretions.
106
Burkholderia pseudomallei found in
Moist soils in southeast asia and northern australia
107
causes melioidosis
Burkholderia pseudomallei
108
Bordetella pertussis characteristics
nonmotile, aerobic, gram-negative
109
cause of pertussis or whooping cough
Bordetella pertussis
110
Neisseria characteristics
aerobic, gram-negative cocci
111
Neisseria usually inhabit
mucous membranes of mammals
112
Neisseria gonorrhoeae
Causative agent of gonorrhoea
113
agent of meningococcal meningitis
N. meningitidi
114
uses fimbriae and an outer membrane protein called Opa to attach to host cells. After the (red) bacterium attaches, the (green) host cell membrane surrounds it
Neisseria gonorrhoeae.
115
How do fimbriae contribute to pathogenicity?
helping bacteria adhere to surfaces and invade host cells
116
As they grow, Zoogloea bacteria form
fluffy, slimy masses that are essential to the proper operation of aerobic sewage treatment
117
largest subgroup of the proteobacteria and include a great variety of physiological types
Gammaproteobacteria
118
Thiomargarita namibiensis,
the largest known bacterium but also exhibits several unusual characteristics
119
Thiotrichales Beggiatoa
nutritionally distinctive
120
pathogen causing tularemia
Francisella tularensis
121
Beggiatoa species grows in
unusual genus that grows the only in aquatic sediments between aerobic and anaerobic layers
122
Morphologically, the genus resembles certain filamentous cyanobacteria, but it is not photosynthetic
Beggiatoa
123
Its motility is enabled by the production of slime
Beggiatoa
124
How does slime aid motility?
attaches to the surface on which movement occurs and provides lubrication, allowing the organism to glide
125
Francisella
F. tularensis:
causes tularemia
126
Pseudomonadales
Pseudomonas are what kind of pathogens?
Opportunistic pathogens; nosocomial infections
127
Pseudomonadales
Pseudomonas
metabolism
Metabolically diverse
128
Motility of pseudomonas
Polar flagella; common in soil
129
P. aeruginosa
Pseudomona found in wound and urinary tract infections
130
use hydrogen sulfide (H2S) as an energy source and accumulates internal granules of sulfur.
Beggiatoa
131
small, pleomorphic bacteria that grow only on complex media enriched with blood or tissue extracts
Francisella
132
Pseudomondales characteristics
gram-negative aerobic rods or cocci.
133
Most important genus in pseudomondales group is
pseudomonas
134
Pseudomonadales order also includes
Azotobacter, Azomonas, Moraxella, Acinetobacter.
135
Pseudomonads are very common in
soil and other natural environments
136
Pseudomonas (soo’dō-MŌ-nas) consists of which characteristics?
1.aerobic, 2.gram-negative rods that are motile by
3. polar flagella, either single or in tufts.
137
Azotobacter and Azomonas role
Nitrogen-fixing
138
Moraxella
M. lacunata
causes conjunctivitis
139
Acinetobacter
A. baumanii
respiratory pathogen; resistant to antibiotics
140
Legionellales genuses
1. Legionella
2. Coxiella
141
Legionella found in
Found in streams, warm-water pipes, and cooling towers
Causes legionellosis
142
Coxiella burnetii effect & transmission
causes Q fever; transmitted via aerosols or milk
143
Coxiella Burnetti is resistant because
it has an endopspore-like body
144
Vibrionales
Found in
aquatic habitats
145
V. cholerae
causes cholera
146
V. parahaemolyticus causes which disease
causes gastroenteritis
147
Enterobacteriales
Commonly called
enterics-inhabit the intestinal tract
148
enterobacteriales action
ferment carbohydrates
149
Enterobacteriales anaerobic or aerobic?
Faculative anaerobes
150
Enterobacteriales have what kind of flagella
Peritrichious flagella: all over surface
151
Escherichia is a type of
enetrobacteriales
152
E. coli
indicator of fecal contamination; causes foodborne disease and urinary tract infections
153
Salmonella
2,500 serovars
Common form of foodborne illness
154
salmonella is a type of
Enterobacteriales
155
Salmonella typhi causes
typhoid fever
156
Shigella is a type of
enterobacteriales
157
Shigella causes which disease
Causes bacillary dysentery
158
K. pneumoniae
causes pneumonia
159
Klebsiella
K. pneumoniae type of enetrobacteriales
160
Serratia
Produces
red pigment
161
Common cause of nosocomial infections
Serratia
162
Serratia is a type of
Enterobacteriales
163
Swarming motility; colonies form concentric rings
Proteus
164
Y. pestis causes plague
Transmitted via fleas
Yesernia
165
Erwinia
Plant pathogens
166
Yersinia, proteus and erwinia are types of
Enterobacteriales
167
Enterobacter
E. cloacae and E. aerogenes diseases
cause urinary tract infections and nosocomial infections
168
Cronobacter discovered in
Discovered in 2007
169
C. sakazakii disease and location
meningitis; found in a variety of environments and foods
170
Pasteurellales
Pasteurella
Pathogen of domestic animals
171
P. multocida mode of transmission
is transmitted to humans via animal bites
172
Haemophilus require
X factor (heme) and V factor (NAD+, NADP+) in media
173
H influenzae causes
causes meningitis, earaches, and epiglottitis
174
H. influenzae does not cause
influenza, influenza is caused by influenza virus, not bacteria
175
Bdellovibrio
Attacks other gram-negative bacteria
176
Desulfovibrionales uses what as final electron acceptor?
S0 or SO4 2- instead of O2
177
Desulfovibrio is found in
anaerobic sediments and intestinal tracts
178
Myxo
mucus
179
Myxococcales move by
gliding and leave a slime trail
180
Cells aggregate and form a fruiting body containing
myxospores
181
Myxospores
resistant resting cells released from sporangioles upon favorable conditions
182
species of pseudomonads excrete pigments
extracellular, water- soluble pigments that diffuse into their media
183
produces a soluble, blue-green pigmentation.
pseudomonas aeruginosa
184
Epsilon proteobacteria are
Helical or curved; microaerophilic
185
Campylobacter flagellum
One polar flagellum
186
C. jejuni
causes foodborne intestinal disease
187
Helicobacter
flagella
Multiple flagella
188
Helicobacter diseases
Cause peptic ulcers and stomach cancer
189
Function of cyanobactera
Carry out oxygenic photosynthesis
190
Many cyanobacteria contain
heterocysts that can fix nitroge
191
heterocysts
can fix nitrogen
192
named for their characteristic blue-green (cyan) pigmentation, were once called blue-green algae.
cyanobacteria
193
Although they resemble the eukaryotic algae and often occupy the same environmental niches, cyanobacteria is not
algae, although, they do carry out photosynthesis
194
most cyanobacteria are capable of
nitrogen fixation
195
heterocysts
contain enzymes that fix nitrogen gas (N2) into ammonium
196
cyanobacteria and Species that grow in water usually have gas vacuoles that
provide buoyancy
197
Shape of cyanobacteria colony
Can be filamentous or unicellular
198
anoxygenic photosynthetic bacteria
Phyla Chlorobi and Chloroflexi
199
Equation for anoxygenic photosynthesis
2 H2S + CO ---> (CH2O) + H2O + 2S0
200
Green sulfur bacteria belong to which phylum?
Chlorobi
201
Green non-sulfur bacteria belong to which phylum
phylum Chloroflexi
202
Purple sulfur and purple non-sulfur photosynthetic bacteria are what kind of bacteria?
proteobacteria
203
Anabaena photosynthesis
1.Plantlike photosynthesis; some
2.use bacterial photosynthesis under anaerobic conditions
204
Green nonsulfur bacteria ex
Chloroflexus
205
Green sulfur bacteria ex
Chlorobium
206
Purple nonsulfur bacteria ex
Rhodospirilum
207
Purple sulfur bacteria ex
Chromatium
208
No peptidoglycan in the cell wall; grow intracellularly
Chlamydiae
209
Chlamydia and Chlamydophila form an
elementary body that is infective
210
elementary body
infectious form of chlamydiae
211
Chlamydia trachomatis
causes trachoma and urethritis
212
Chlamydophila psittaci
causes respiratory psittacosis
213
Chlamydophila pneumoniae
causes a mild form of pneumonia prevalent in young adults
214
have a unique developmental cycle that is perhaps their most distinguishing characteristic
Chlamydias
215
Chlamydias gram positive or gram negative?
gram-negative
216
Chlamydias are transmitted to humans by
interpersonal contact or by airborne respiratory routes
217
Gemmata obscu riglobus
has a membrane around D N A, resembling an eukaryotic nucleus
218
Nonproteobacteria are gram positive or gram negative?
Gram negative
219
Types of nonproteobacteria
1. Bacteroidetes
2. Fusobacteria
220
Bacterioidetes are aerobic or anaerobic?
Anaerobic
221
Bacteroides are found in
the mouth and large intestine
222
Cytophaga degrade
cellulose in soil
223
Fusobacteria are aerobic or anaerobic?
anaerobic
224
Fusobacteria are found in
mouth, cause dental abscesses
225
Spirochaetes
Coiled and move via axial filaments
226
Examples of Spirochaetes
1. Treponema
2. Borrelia
3. Leptospira
227
Treponema pallidum causes
syphylis
228
Causes relapsing fever and lyme disease
Borrelia
229
Leptospira
excreted in animal urine
230
Deinococcus radiodurans more resistant to
radiation than endospores
231
Thermus aquaticus found in
hot spring in Yellowstone national part
232
Source of Taq polymerase
Thermus aquaticus
233
Which gram-negative group has a life cycle that includes different stages?
Chlamydia
234
Both the purple and green photosynthetic bacteria and the photosynthetic cyanobacteria use plantlike CO2 fixation to make carbohydrates. In what way does the photosynthesis carried out by these two groups differ from plant photosynthesis?
they do not use water as an electron donor and therefore do not produce oxygen as a byproduct
235
The Axial filament distinguishes what genera of bacteria
Spirochetes
236
Firmicutes,
Tenericutes,
Actinobacteria are all gram positive or gram negative?
Gram positive
237
Firmicutes G+C ratios
Low G+C ratios
238
Tenericutes G+C ratios
low G+C ratios
239
Actinobacteria G+C ratio
high G+C ratios
240
Clostridiales are type of
firmicutes
241
Clostridium aerobic vs anaerobic
And makes
Endospore-producing
Obligate anaerobes
242
Includes disease-causing C. tetani, C. botulinum, C. perfringens, and C. difficile
Clostridium
243
Epulopiscium are a type of
firmicutes
244
Epulopiscium can be seen with
naked eye
245
Epulopiscium cells form within
parent cell; no binary fission
246
Bacillales are a type of
Firmucute
247
Bacillus
Endospore-producing rods
248
B. anthracis
causes anthrax
249
B. thuringiensis
is an insect pathogen
250
B. cereus
causes food poisoning
251
Staphylococcus
Grape-like clusters
252
S. aureus causes
wound infections, often antibiotic resistant, makes an enterotoxin
253
Lactobacillales are a type of
firmicutes
254
Lactobacillales are what kind of anaerobes?
Aerotolerant anaerobes
255
Lactobacillales produce lactic acid from
simple carbohydrates
256
Lactobacillus
colonize the body and are used commercially in food production
257
Streptococcus are a type of
lactobacillales
258
streptococcus produce
enzymes that destroy tissue
259
Beta-hemolytic streptococci hemolyze
blood agar
260
S. pyogenes
type of Beta-hemolytic group
261
beta-hemolytic species produce a
hemolysin that forms a clear zone of hemolysis on blood agar. causes clear areas around the colonies
262
Principal pathogen of streptococci
S. pyogenes
263
Non-beta-hemolytic streptococci include
S. pneumoniae
S. mutans
264
S. mutans
causes dental caries
265
Lactobacillales-important members of which genus?
Streptococcus
266
Beta-hemolytic streptococci examples
S. pyogenes and S. agalactiae
267
Beta-hemolytic streptococci subdivided into Groups
A through G
268
S. pneumoniae and S. mutans often exhibit
alpha hemolysis
269
Enterococcus type of
type of lactobacillales
270
Eneterococcus found in
intestinal tract; hospital contaminants
271
E. faecalis and E. faecium infect
surgical wounds and the urinary tract
272
E. faecalis and E. facecium are examples of which genus?
Enterococcus
273
Listeria monocytogenes
contaminates food
274
Pleomorphic
lack a cell wall
275
Low G+C Gram positive bacteria
Tenericutes
276
Mycoplasma are pleomorphic bacteria, meaning
they lack a cell wall
277
Mycoplasma pneumonia causes a
mild pneumonia
278
To which genus is Enterococcus more closely related: Staphylococcus or Lactobacillus?
Lactobacillus; they are in the same phylum and class
279
Actinobacteria
high G+C
Gram positive
280
Often pleomorphic; branching filaments
Often common inhabitants of soil
Actinobacteria
281
Mycobacterium belong to which phylum?
Actinobacteria
282
Growth of mycobacterium
slow-growing
283
Mycobacterium tuberculosis causes
tuberculosis
284
Mycobacterium leprae causes
leprosy
285
Corynebacterium belong to which phylum?
Actinobacteria
286
C. diphtheriae
causes diptheria
287
Propionibacterium
forms
propionic acid
288
P. acnes
causes acne
289
Propionibacterium belongs to which phylum?
actinobacteria
290
Gardanella vaginalis
causes vaginitis
291
Gardnerella is part of which phyllum?
Actinobacteria
292
Frankia is part of which phylum?
Actinobacteria
293
Frankia forms
Forms N-fixing nodules on tree roots
294
Streptomyces
Isolated from soil; produce most antibiotics
295
Actinomyces
Form filaments in the mouth and throat; destroy tissue
296
Nocardia
Form fragmenting filaments; acid-fast
297
N. asteroides
causes pulmonary infections
298
What group of bacteria makes most of the commercially important antibiotics?
Streptomyces
299
Distinct taxonomic grouping; lack peptidoglycan
Archaea
300
Halophiles
Require salt concentration >25%
301
Thermophiles
Require growth temperature > 80C
302
Methanogens aerobic or anaerobic
Anaerobic and produce methane
303
What kind of archaea would populate solar evaporating ponds?
halophiles and thermophiles
304
List two factors that contribute to the limits of our knowledge of microbial diversity.
1. cannot be cultivated with the media and conditions normally used for bacterial growth in a lab
2. some bacteria are part of complex food chains and can grow only in the presence of other microbes
305
Thiomargarita diameter
750 micrometers
306
Carsonella ruddii size
182 genes
307
P C R indicates perhaps __________ or more bacterial species per gram of soil
10,000
308
How can you detect the presence of a bacterium that cannot be cultured?
PCR
309
Sphaerotilus is found in
Found in freshwater and sewage
310
Anabena is a type of
Type of cyanobacteria
311
Pseudomondales gram positive or gram negative?
gram-negative
312
Pseudomondales aerobic or anaerobic?
aerobic
313
Shape of pseudomondales
rods or cocci.
314
Sphaerotilus motility
polar flagella
315
Sphaerotilus special characteristics
Sheathed
316
Sphaerotilus special characteristics
Sheathed
317
Rickettsias shape
rod-shaped bacteria, or coccobacilli
318
Burkholderia cepacia gram negative vs gram positive
gram-negative
319
Burkholderia cepacia shape
rod, best known
320
Chlamydias shape
coccoid bacteria
321
often antibiotic resistant, makes an enterotoxin
S. Aureus
