Chap 11 Flashcards
The Prokaryotes: Domains Bacteria and Archaea
Prokaryotes in Bergey’s manual are grouped into two domains
Archaea & Bacteria
Domain of prokaryotic cells lacking in peptidoglycan
archaea
bacteria are also commonly distinguished by gram staining
gram positive or gram negative
proteobacteria characteristics
1.Gram-negative,
2.chemoheterotrophic bacteria that posses a
3.signature rRNA sequence
proteobacteria are thought to have arised from
a common photosynthetic ancestor
Largest taxonomic group of bacteria
proteobacteria
Few proteobacteria are
photosynthetic, other capacities have replaced this characteristic
The phylogenetic relationship between proteobacteria is based upon
rRNA studies
The name proteobacteria comes from
Greek god Proteus, who could take many shapes
Proteobacteria are designated into five classes
- alphaproteobacteria
- beta
- gamma
- delta
- epsilon
Alphaproteobacteria capable of growth with very low levels of ______
nutrients
prosthecae
unusual stalks or buds that grow out of alphaproteobacteria
prostheca
a stalk or bud protruding from a prokaryotic cell
Include agriculturally important bacteria capable of nitrogen fixation
alphaproteobacteria
Pelagibacter Ubique
most abundant living organism in the oceans on the basis of weight.
Thought to have an important role in the earth’s carbon cycle
P. ubique
P. Ubique has a small size and small genome, which allows it to
survive in low-nutrient environment
size of P. ubique
0.3 micrometers in diameter
Which bacteria have the smallest genomes?
bacteria in symbiotic relationships because they have lower metabolic requirements
What has a smaller genome than P. ubique?
several mycoplasmas
has only 1354 genes
P. Ubique
first member of SAR 11 group to be successfully cultivated
P. ubique
Azospirilum
soil bacterium; grows closely associated to roots, especially in tropical grasses. Uses nutrients excreted from the plants to fix nitrogen from atmosphere.
azo-
nitrogen fixing
azo- comes from
without life, nitrogen associated with no life
Acetobacteraceae & Gluconobacter
industrially important 1. aerobic organisms that
2.convert ethanol into acetic acid (vinegar).
Granulibacter
emerging; found in patients with chronic granulomatous disease.
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
In the second edition they are now widely separated.
Rickettsias, chlamydias, and viruses
Contain a single type of nucleic acid, either DNA or RNA
viruses
Contain a protein coat (sometimes itself enclosed by an envelope of lipids, proteins, and carbohydrates) that surrounds the nucleic acid.
viruses
Multiply inside living cells by using the synthesizing machinery of the cell
viruses
Cause the synthesis of specialized structures that can transfer the viral nucleic acid to other cells.
viruses
Rickettsias gram negative or gram positive?
gram-negative
One distinguishing feature of most rickettsias
transmitted to humans by insect and tick bites
Rickettsia enter their host cell by
Inducing phagocytosis. They quickly enter the cytoplasm of the cell and begin reproducing by binary fission
Rickettsias can usually be cultivated artificially in
cell culture or chick embryos
are responsible for a number of diseases known as the spotted fever group.
Rickettsias
epidemic typhus, caused by
Rickettsia prowazekii
Epidemic typhus is transmitted by
transmitted by lice
endemic murine typhus, caused by
R. typhi
endemic murine typhus, transmitted by
rat fleas
Rocky Mountain spotted fever, caused by
R. rickettsii, transmitted by ticks
In humans, rickettsial infections damage
The permeability of blood capillaries, which results in a characteristic spotted rash.
Ehrlichia
1.gram-negative, 2.rickettsia-like bacteria that
3. live obligately within white blood cells
Ehrlichia species are transmitted by
ticks to humans
cause ehrlichiosis, a sometimes fatal disease
Ehrlichia
Caulobacter and Hyphomicrobium found in
low-nutrient aquatic environments, Lakes
Have stalks that anchor the organisms to surfaces
Caulobacter and Hyphomicrobium
Waht is the function of the stalk in Caulobacter and Hyphomicrobium?
Increases nutrient uptake
How does the stalk increase nutrient uptake?
-exposed to changing flow of water, increases surface area,
-can use host excretions as nutrients
When does the stalk grow?
When the nutrient concentration is exceptionally low, to pick up more food
Budding bacteria don’t divide by
binary fission into two identical cells
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.
Hyphomicrobium found in
in low-nutrient aquatic environments
Caulobacter and Hyphomicrobium reproduce by
budding rather than binary fission
Both Caulobacter and Hyphomicrobium produce prominent
prosthecae
Rhizobium, Bradyrhizobium infect
roots of leguminous plants, such as beans, peas, or clover
common name of Rhizobium, Bradyrhizobium
rhizobia
presence of rhizobia in the roots leads to
formulation of nodules;
Rhizobia and plant form a symbiotic relationship that results in
fixation of nitrogen from the air so it can be used by the plant
Agrobacterium can invade
plants
can invade plants but these bacteria do not induce root nodules or fix nitrogen
Agrobacterium
Agrobacterium tumefaciens causes a disease called
crown gall
Plant crown
Area of plant where roots and stem merge
How does crown gall occur?
A. tumefaciens inserts a plasmid containing bacterial genetic information into the plant’s chromosomal DNA
Plasmids
most common vector that scientists use to carry new genes into a plant cell
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
Genus __________ has several members that are human pathogens
Bartonella
Bartonella henselae
1.gram-negative bacillus that
2.causes cat-scratch disease
Brucella
obligate parasites of mammals, cause of brucellosis
small nonmotile coccobacilli, cause brucellosis
Brucella
Brucella can survive
phagocytosis
Nitrobacter and Nitrosomonas are important to
environment and agriculture; nitrifying bacteria
Obligate parasite of mammals; survives phagocytosis
Causes brucellosis
Brucella
Nitrobacter and Nitrosomonas are chemoautotrophic, meaning
use inorganic chemicals as energy source; CO2 as carbon source
Nitrosomonas equation
NH4 —> NO2-
Nitrobacter equation
NO2- —> NO3-
Wolbachia
Endosymbiont of insects
Affects reproduction of insects
The energy sources of the genera Nitrobacter and Nitrosomonas (the latter is a member of the betaproteobacteria) are
reduced nitrogenous compounds
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.
most common infectious bacterial genus in the world
Wolbachia
Wolbachia live only inside the cells of
their hosts
hosts of wolbachia are usually
Insects
escapes detection by the usual culture methods.
Wolbachia
interferes with reproduction and egg development in infected insects.
Wolbachia
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
The Betaproteobacteria
- Acidithiobacillus
- Spirillum
- Sphaerotilus
Found in freshwater
Move via flagella
Spirirlum
Acidithiobacillus
1.Chemoautotrophic;
2.oxidize sulfur to sulfates:
H2S —> SO4 2-
Sphaerotilus function
Form sheaths to aid in protection and nutrient gathering
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.
sulfur-oxidizing bacteria are important in the sulfur cycle
Acidithiobacillus
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
________ bacteria are motile by conventional polar flagella
Spirillum
Relatively large, gram-negative, aerobic bacteria.
Spirilla
Sphaerotilus gram negative or gram positive?
- gram-negative
Sheaths aid in
protection and nutrient accumulation
Sphaerotilus natans contributes to
bulking in sewage
can eventually swim free of the sheath.
Sphaerotilus
Burkholderia motile by
single polar flagellum or tuft of flagella
Burkholderia cepacia aerobic vs anaerobic
aerobic,
nutritional spectrum of Burkholderia cepacia
capable of degrading more than 100 different organic molecules.
The large nutritional spectrum of burkholderia is a problem because
bacteria can grow in diinfectant solutions. Contamination of equipment and drugs in hospitals
Why is burkholderia a problem for people with genetic lung disease cystic fibrosis,?
it metabolizes accumulated respiratory secretions.
Burkholderia pseudomallei found in
Moist soils in southeast asia and northern australia
causes melioidosis
Burkholderia pseudomallei
Bordetella pertussis characteristics
nonmotile, aerobic, gram-negative
cause of pertussis or whooping cough
Bordetella pertussis
Neisseria characteristics
aerobic, gram-negative cocci
Neisseria usually inhabit
mucous membranes of mammals
Neisseria gonorrhoeae
Causative agent of gonorrhoea
agent of meningococcal meningitis
N. meningitidi
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.
How do fimbriae contribute to pathogenicity?
helping bacteria adhere to surfaces and invade host cells
As they grow, Zoogloea bacteria form
fluffy, slimy masses that are essential to the proper operation of aerobic sewage treatment
largest subgroup of the proteobacteria and include a great variety of physiological types
Gammaproteobacteria
Thiomargarita namibiensis,
the largest known bacterium but also exhibits several unusual characteristics
Thiotrichales Beggiatoa
nutritionally distinctive
pathogen causing tularemia
Francisella tularensis
Beggiatoa species grows in
unusual genus that grows the only in aquatic sediments between aerobic and anaerobic layers
Morphologically, the genus resembles certain filamentous cyanobacteria, but it is not photosynthetic
Beggiatoa
Its motility is enabled by the production of slime
Beggiatoa
How does slime aid motility?
attaches to the surface on which movement occurs and provides lubrication, allowing the organism to glide
Francisella
F. tularensis:
causes tularemia
Pseudomonadales
Pseudomonas are what kind of pathogens?
Opportunistic pathogens; nosocomial infections
Pseudomonadales
Pseudomonas
metabolism
Metabolically diverse
Motility of pseudomonas
Polar flagella; common in soil
P. aeruginosa
Pseudomona found in wound and urinary tract infections
use hydrogen sulfide (H2S) as an energy source and accumulates internal granules of sulfur.
Beggiatoa
small, pleomorphic bacteria that grow only on complex media enriched with blood or tissue extracts
Francisella
Pseudomondales characteristics
gram-negative aerobic rods or cocci.
Most important genus in pseudomondales group is
pseudomonas
Pseudomonadales order also includes
Azotobacter, Azomonas, Moraxella, Acinetobacter.
Pseudomonads are very common in
soil and other natural environments
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.
Azotobacter and Azomonas role
Nitrogen-fixing
Moraxella
M. lacunata
causes conjunctivitis
Acinetobacter
A. baumanii
respiratory pathogen; resistant to antibiotics
Legionellales genuses
- Legionella
- Coxiella
Legionella found in
Found in streams, warm-water pipes, and cooling towers
Causes legionellosis
Coxiella burnetii effect & transmission
causes Q fever; transmitted via aerosols or milk
Coxiella Burnetti is resistant because
it has an endopspore-like body
Vibrionales
Found in
aquatic habitats
V. cholerae
causes cholera
V. parahaemolyticus causes which disease
causes gastroenteritis
Enterobacteriales
Commonly called
enterics-inhabit the intestinal tract
enterobacteriales action
ferment carbohydrates
Enterobacteriales anaerobic or aerobic?
Faculative anaerobes
Enterobacteriales have what kind of flagella
Peritrichious flagella: all over surface
Escherichia is a type of
enetrobacteriales
E. coli
indicator of fecal contamination; causes foodborne disease and urinary tract infections
Salmonella
2,500 serovars
Common form of foodborne illness
salmonella is a type of
Enterobacteriales
Salmonella typhi causes
typhoid fever
Shigella is a type of
enterobacteriales
Shigella causes which disease
Causes bacillary dysentery
K. pneumoniae
causes pneumonia
Klebsiella
K. pneumoniae type of enetrobacteriales
Serratia
Produces
red pigment
Common cause of nosocomial infections
Serratia
Serratia is a type of
Enterobacteriales
Swarming motility; colonies form concentric rings
Proteus
Y. pestis causes plague
Transmitted via fleas
Yesernia
Erwinia
Plant pathogens
Yersinia, proteus and erwinia are types of
Enterobacteriales
Enterobacter
E. cloacae and E. aerogenes diseases
cause urinary tract infections and nosocomial infections
Cronobacter discovered in
Discovered in 2007
C. sakazakii disease and location
meningitis; found in a variety of environments and foods
Pasteurellales
Pasteurella
Pathogen of domestic animals
P. multocida mode of transmission
is transmitted to humans via animal bites
Haemophilus require
X factor (heme) and V factor (NAD+, NADP+) in media
H influenzae causes
causes meningitis, earaches, and epiglottitis
H. influenzae does not cause
influenza, influenza is caused by influenza virus, not bacteria
Bdellovibrio
Attacks other gram-negative bacteria
Desulfovibrionales uses what as final electron acceptor?
S0 or SO4 2- instead of O2
Desulfovibrio is found in
anaerobic sediments and intestinal tracts
Myxo
mucus
Myxococcales move by
gliding and leave a slime trail
Cells aggregate and form a fruiting body containing
myxospores
Myxospores
resistant resting cells released from sporangioles upon favorable conditions
species of pseudomonads excrete pigments
extracellular, water- soluble pigments that diffuse into their media
produces a soluble, blue-green pigmentation.
pseudomonas aeruginosa
Epsilon proteobacteria are
Helical or curved; microaerophilic
Campylobacter flagellum
One polar flagellum
C. jejuni
causes foodborne intestinal disease
Helicobacter
flagella
Multiple flagella
Helicobacter diseases
Cause peptic ulcers and stomach cancer
Function of cyanobactera
Carry out oxygenic photosynthesis
Many cyanobacteria contain
heterocysts that can fix nitroge
heterocysts
can fix nitrogen
named for their characteristic blue-green (cyan) pigmentation, were once called blue-green algae.
cyanobacteria
Although they resemble the eukaryotic algae and often occupy the same environmental niches, cyanobacteria is not
algae, although, they do carry out photosynthesis
most cyanobacteria are capable of
nitrogen fixation
heterocysts
contain enzymes that fix nitrogen gas (N2) into ammonium
cyanobacteria and Species that grow in water usually have gas vacuoles that
provide buoyancy
Shape of cyanobacteria colony
Can be filamentous or unicellular
anoxygenic photosynthetic bacteria
Phyla Chlorobi and Chloroflexi
Equation for anoxygenic photosynthesis
2 H2S + CO —> (CH2O) + H2O + 2S0
Green sulfur bacteria belong to which phylum?
Chlorobi
Green non-sulfur bacteria belong to which phylum
phylum Chloroflexi
Purple sulfur and purple non-sulfur photosynthetic bacteria are what kind of bacteria?
proteobacteria
Anabaena photosynthesis
1.Plantlike photosynthesis; some
2.use bacterial photosynthesis under anaerobic conditions
Green nonsulfur bacteria ex
Chloroflexus
Green sulfur bacteria ex
Chlorobium
Purple nonsulfur bacteria ex
Rhodospirilum
Purple sulfur bacteria ex
Chromatium
No peptidoglycan in the cell wall; grow intracellularly
Chlamydiae
Chlamydia and Chlamydophila form an
elementary body that is infective
elementary body
infectious form of chlamydiae
Chlamydia trachomatis
causes trachoma and urethritis
Chlamydophila psittaci
causes respiratory psittacosis
Chlamydophila pneumoniae
causes a mild form of pneumonia prevalent in young adults
have a unique developmental cycle that is perhaps their most distinguishing characteristic
Chlamydias
Chlamydias gram positive or gram negative?
gram-negative
Chlamydias are transmitted to humans by
interpersonal contact or by airborne respiratory routes
Gemmata obscu riglobus
has a membrane around D N A, resembling an eukaryotic nucleus
Nonproteobacteria are gram positive or gram negative?
Gram negative
Types of nonproteobacteria
- Bacteroidetes
- Fusobacteria
Bacterioidetes are aerobic or anaerobic?
Anaerobic
Bacteroides are found in
the mouth and large intestine
Cytophaga degrade
cellulose in soil
Fusobacteria are aerobic or anaerobic?
anaerobic
Fusobacteria are found in
mouth, cause dental abscesses
Spirochaetes
Coiled and move via axial filaments
Examples of Spirochaetes
- Treponema
- Borrelia
- Leptospira
Treponema pallidum causes
syphylis
Causes relapsing fever and lyme disease
Borrelia
Leptospira
excreted in animal urine
Deinococcus radiodurans more resistant to
radiation than endospores
Thermus aquaticus found in
hot spring in Yellowstone national part
Source of Taq polymerase
Thermus aquaticus
Which gram-negative group has a life cycle that includes different stages?
Chlamydia
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
The Axial filament distinguishes what genera of bacteria
Spirochetes
Firmicutes,
Tenericutes,
Actinobacteria are all gram positive or gram negative?
Gram positive
Firmicutes G+C ratios
Low G+C ratios
Tenericutes G+C ratios
low G+C ratios
Actinobacteria G+C ratio
high G+C ratios
Clostridiales are type of
firmicutes
Clostridium aerobic vs anaerobic
And makes
Endospore-producing
Obligate anaerobes
Includes disease-causing C. tetani, C. botulinum, C. perfringens, and C. difficile
Clostridium
Epulopiscium are a type of
firmicutes
Epulopiscium can be seen with
naked eye
Epulopiscium cells form within
parent cell; no binary fission
Bacillales are a type of
Firmucute
Bacillus
Endospore-producing rods
B. anthracis
causes anthrax
B. thuringiensis
is an insect pathogen
B. cereus
causes food poisoning
Staphylococcus
Grape-like clusters
S. aureus causes
wound infections, often antibiotic resistant, makes an enterotoxin
Lactobacillales are a type of
firmicutes
Lactobacillales are what kind of anaerobes?
Aerotolerant anaerobes
Lactobacillales produce lactic acid from
simple carbohydrates
Lactobacillus
colonize the body and are used commercially in food production
Streptococcus are a type of
lactobacillales
streptococcus produce
enzymes that destroy tissue
Beta-hemolytic streptococci hemolyze
blood agar
S. pyogenes
type of Beta-hemolytic group
beta-hemolytic species produce a
hemolysin that forms a clear zone of hemolysis on blood agar. causes clear areas around the colonies
Principal pathogen of streptococci
S. pyogenes
Non-beta-hemolytic streptococci include
S. pneumoniae
S. mutans
S. mutans
causes dental caries
Lactobacillales-important members of which genus?
Streptococcus
Beta-hemolytic streptococci examples
S. pyogenes and S. agalactiae
Beta-hemolytic streptococci subdivided into Groups
A through G
S. pneumoniae and S. mutans often exhibit
alpha hemolysis
Enterococcus type of
type of lactobacillales
Eneterococcus found in
intestinal tract; hospital contaminants
E. faecalis and E. faecium infect
surgical wounds and the urinary tract
E. faecalis and E. facecium are examples of which genus?
Enterococcus
Listeria monocytogenes
contaminates food
Pleomorphic
lack a cell wall
Low G+C Gram positive bacteria
Tenericutes
Mycoplasma are pleomorphic bacteria, meaning
they lack a cell wall
Mycoplasma pneumonia causes a
mild pneumonia
To which genus is Enterococcus more closely related: Staphylococcus or Lactobacillus?
Lactobacillus; they are in the same phylum and class
Actinobacteria
high G+C
Gram positive
Often pleomorphic; branching filaments
Often common inhabitants of soil
Actinobacteria
Mycobacterium belong to which phylum?
Actinobacteria
Growth of mycobacterium
slow-growing
Mycobacterium tuberculosis causes
tuberculosis
Mycobacterium leprae causes
leprosy
Corynebacterium belong to which phylum?
Actinobacteria
C. diphtheriae
causes diptheria
Propionibacterium
forms
propionic acid
P. acnes
causes acne
Propionibacterium belongs to which phylum?
actinobacteria
Gardanella vaginalis
causes vaginitis
Gardnerella is part of which phyllum?
Actinobacteria
Frankia is part of which phylum?
Actinobacteria
Frankia forms
Forms N-fixing nodules on tree roots
Streptomyces
Isolated from soil; produce most antibiotics
Actinomyces
Form filaments in the mouth and throat; destroy tissue
Nocardia
Form fragmenting filaments; acid-fast
N. asteroides
causes pulmonary infections
What group of bacteria makes most of the commercially important antibiotics?
Streptomyces
Distinct taxonomic grouping; lack peptidoglycan
Archaea
Halophiles
Require salt concentration >25%
Thermophiles
Require growth temperature > 80C
Methanogens aerobic or anaerobic
Anaerobic and produce methane
What kind of archaea would populate solar evaporating ponds?
halophiles and thermophiles
List two factors that contribute to the limits of our knowledge of microbial diversity.
- cannot be cultivated with the media and conditions normally used for bacterial growth in a lab
- some bacteria are part of complex food chains and can grow only in the presence of other microbes
Thiomargarita diameter
750 micrometers
Carsonella ruddii size
182 genes
P C R indicates perhaps __________ or more bacterial species per gram of soil
10,000
How can you detect the presence of a bacterium that cannot be cultured?
PCR
Sphaerotilus is found in
Found in freshwater and sewage
Anabena is a type of
Type of cyanobacteria
Pseudomondales gram positive or gram negative?
gram-negative
Pseudomondales aerobic or anaerobic?
aerobic
Shape of pseudomondales
rods or cocci.
Sphaerotilus motility
polar flagella
Sphaerotilus special characteristics
Sheathed
Sphaerotilus special characteristics
Sheathed
Rickettsias shape
rod-shaped bacteria, or coccobacilli
Burkholderia cepacia gram negative vs gram positive
gram-negative
Burkholderia cepacia shape
rod, best known
Chlamydias shape
coccoid bacteria
often antibiotic resistant, makes an enterotoxin
S. Aureus
