Deck 17: Bacteria: the Proteobacteria

Question 1

Which of the following is NOT a trait of bioluminescent bacteria?

A) They are luminescent only in the presence of oxygen.
B) Most inhabit soil environments.
C) Autoinduction of luminescence requires dense populations.
D) The enzyme luciferase and a long- chain aliphatic aldehyde are required for bioluminescence.

Answer 1

B

Question 2

Mud, lake water, or a sewage sample inoculated into mineral salts medium supplemented with an organic acid as the carbon source, lacking fixed or organic nitrogen, and incubated anoxically in the light invariably selects for

A) purple nonsulfur bacteria.
B) purple sulfur bacteria.
C) nitrifying bacteria.
D) green nonsulfur bacteria.

Answer 2

A

Question 3

A gram- negative, nonsporulating rod that is highly motile, oxidase negative, facultatively aerobic, ferments glucose, and urease positive is likely to be of which genus?

A) Rickettsia
B) Pseudomonas
C) Lactobacillus
D) Proteus

Answer 3

D

Question 4

When a bacterium exhibits polar growth,

A) cell division does not involve membrane complexes.
B) new cell wall material forms from a single point.
C) complex internal structures may be formed.
D) all of the above may occur.

Question 5

A broth containing methanol and nitrate is incubated under anaerobic conditions. This medium will select for

A) Hyphomicrobium.
B) Azospirillum.
C) Nitrobacter.
D) Gallionella.

Question 6

Which of the following is NOT a trait of rickettsias?

A) They have not been cultivated in the absence of host cells.
B) They are obligate intracellular parasites.
C) They lack cell walls.
D) Both the host and parasite are required in order to be alive and metabolically active.

Question 7

Which of the following groups are NOT able to carry out anoxygenic photosynthesis?

A) purple phototrophic bacteria
B) purple sulfur bacteria
C) cyanobacteria
D) purple nonsulfur bacteria

Question 8

A gram- negative rod, polar flagellated microbe that ferments sugars to ethanol is probably a(n)

A) Gluconobacter.
B) Zymomonas.
C) Acetobacter.
D) Vibrio.

Question 9

Which of the following statements does NOT apply to magnetotactic bacteria?

A) The bacteria align their long axis at right angles to the lines of the magnetic fields.
B) The cells contain particles of Fe3O4.
C) Magnetic orientation may provide a means for maintaining the organisms in low oxygen levels.
D) In cells from the Northern Hemisphere, magnetosomes align themselves forward with respect to the flagella and move north.

Question 10

Methanotrophs

A) have been found living in the gill tissues of marine mussels on the sea floor.
B) are widespread in nature.
C) are able to oxidize ammonia.
D) All of the above apply to the methanotrophs.

Question 11

Which genus is characterized by these traits: gram- negative, straight or slightly curved rod, polar flagella, oxidase- positive, obligately aerobic, and some chemolithotrophic members?

A) Pseudomonas
B) Serratia
C) Saccharomyces
D) Beijerinckia

Question 12

The most favorable lakes for the development of purple sulfur bacteria are those that are

A) meromictic.
B) oligotrophic.
C) eutrophic.
D) sedimentary.

Question 13

Strains of which genus have had c70% of their genomes hybridized with Escherichia coli?

A) Proteus
B) Salmonella
C) Shigella
D) Campylobacter

Question 14

Which of the following does NOT apply to Bdellovibrio?

A) replicates in periplasmic space
B) obligate aerobe
C) widespread in soil and water
D) attacks gram- positive Bacteria

Question 15

Which bacillus- shaped genus are primarily intracellular parasites of arthropods such as crustaceans and insects?

A) Coxiella
B) Klebsiella
C) Wolbachia
D) Roseospirillum

Question 16

The cyanobacteria are oxygenic phototrophic bacteria with evolutionary roots near those of the

A) deinococci.
B) phototrophic green sulfur bacteria.
C) gram- positive Bacteria.
D) hyperthermophilic hydrogen- oxidizing chemolithotrophs.

Question 17

Luminescence in bacteria is catalyzed by bacterial

A) oxidases.
B) catalase.
C) luciferase.
D) hydrogenase.

Question 18

Which of the following would NOT aid in the enrichment of sulfate reducers?

A) ascorbate or thioglycolate
B) incubation under aerobic conditions
C) ferrous iron
D) lactate- sulfate medium

Question 19

The least derived (or most ancient) phylum contains the genus

A) Propionibacterium.
B) Methylococcus.
C) Rhodospirillum.
D) Aquifex.

Question 20

Which genus oxidizes both ferrous iron (Fe2+) and Mn2+ but obtains energy only from the former?

A) Leptothrix
B) Proteus
C) Sphaerotilus
D) Arcobacter

Question 21

Which of the following is NOT a characteristic of myxobacteria?

A) The organisms may be readily isolated from soil or dead organic matter on nutrient- rich agar.
B) Vegetative cells are gram- negative.
C) The mounding of cells after aggregation leads to fruiting body formation.
D) Myxospores are more resistant to heating and drying than is the vegetative cell.

Question 22

Currently, well over phyla of Bacteria have been identified from sequencing.

Question 23

Which of the following traits is NOT characteristic of Caulobacter?

A) forms rosettes due to the attached stalks of several cells
B) attaches to surfaces in nature
C) abundant in aquatic habitats rich in nutrients
D) produces a cytoplasmic outgrowth (prostheca)

Question 24

A culture of nitrogen- fixing, free- living bacteria is composed of large gram- negative rods that form resting structures called cysts, and is usually found in nature in neutral and alkaline soils. Its genus name is

A) Derxia.
B) Azomonas.
C) Azospirillum.
D) Azotobacter.

Question 25

Which of the following gliding bacteria form(s) fruiting bodies?

A) Cytophaga
B) Myxococcus
C) Beggiatoa
D) all of the above

Question 26

Azospirillum lipoferum is a terrestrial nitrogen- fixing bacterium that often forms a(n)
relationship with .

Question 27

Type I methanotrophs

A) possess bundles of disc- shaped vesicles in internal membranes.
B) are obligate aerobes.
C) use the ribulose monophosphate cycle.
D) do all of the above.

Question 28

Which grouping is gram- negative bacillus- shaped, faculatively anaerobic, and commonly found in the intestines of animals?

A) enteric bacteria
B) acetic acid bacteria
C) pseumonads
D) Epsilonproteobacteria

Question 29

Two broad ecological classes of sulfur- oxidizing bacteria exist: those living at _ and those living at .

Question 30

Scientists studying bioremediation often use environmental strains of _ that is capable of breaking down pesticides and other toxic chemicals.

A) Bacillus
B) Clostridium
C) Staphylococcus
D) Pseudomonas

Question 31

Sheathed bacteria are commonly isolated from

A) freshwater habitats that are rich in organic matter.
B) marine or brackish habitats.
C) human intestinal tracts.
D) fertile soils.

Question 32

Which of the following bacteria is the least phylogenetically related to Desulfovibrio?

A) Desulfomonas
B) Desulfobulbus
C) Desulfotomaculum
D) Desulfobacter

Question 33

Which of the following is NOT correct regarding ammonia oxidation by nitrifying bacteria?

A) The substrate is NH4+.
B) Ammonia monooxygenase is located in an internal membrane system that resembles the photosynthetic membranes in the purple phototrophic bacteria.
C) The initial step involves an ammonia monooxygenase.
D) The oxidation occurs best in waters that receive inputs of sewage or other wastewaters.

Question 34

Which of the following organisms does NOT produce prosthecae?

A) Gallionella
B) Hyphomicrobium
C) Leptothrix
D) Caulobacter

Question 35

is the term used to identify salt- loving bacteria.

Question 36

Experiments with Azotobacter chroococcum have led to the observation that

A) nitrogenase reduces nitrogen to ammonia.
B) acetylene may be reduced by nitrogenase.
C) nitrogenase may contain molybdenum and iron.
D) two alternative nitrogenases can be made under certain growth conditions.

Question 37

What is a major distinction between the hydrogen chemolithotrophs and many sulfur chemolithotrophs and the nitrifying bacteria?

A) Hydrogen chemolithotrophs cannot be cultured in vitro, whereas the sulfur chemolithotrophs and nitrifying bacteria can easily be cultured.
B) Hydrogen chemolithotrophs are almost all facultative chemolithotrophs; the sulfur chemolithotrophs and nitrifying bacteria are nearly all obligate chemolithotrophs.
C) Hydrogen chemolithotrophs are found in dry environments, while sulfur chemolithotrophs and nitrifying bacteria are found in aquatic environments.
D) Hydrogen chemolithotrophs are anaerobes, whereas the sulfur chemolithotrophs and nitrifying bacteria are aerobes.

Question 38

Campylobacter and Helicobacter are two genera within the class of Proteobacteria.

A) Delta
B) Epsilon
C) Alpha
D) Beta

Question 39

Pseudomonas aeruginosa is naturally resistant to many of the widely used antibiotics due to the presence of a(n) .

Question 40

The structures often present in cells of obligate chemolithotrophs and which contain high levels of Calvin cycle enzymes (such as RuBisCO) are known as

A) lysosomes.
B) carboxysomes.
C) inclusion bodies.
D) peroxisomes.

Question 41

The very large Spirillum volutans, which was observed by the earliest microscopists, is microaerophilic.

Question 42

Some species of luminous bacteria colonize specialized organs of certain marine fishes and squids and produce light that the animal uses for signaling, avoiding predators, and attracting prey.

Question 43

Members of the genus can be isolated from the intestines of homeothermic animals (such as humans) and poikilothermic animals (such as lizards and turtles).

Question 44

The bacteria are commonly found in alcoholic juices such as hard cider, wine, or beer.

Question 45

The oxidation of ammonia to nitrite is carried out by the bacteria. The product of this step is subsequently oxidized to nitrate by the _ bacteria.

Question 46

Gliding myxobacteria often form multicellular structures called . These bacteria have also developed intercellular _ .

Question 47

Methane produced in the anoxic regions of lakes rises through the water column, and methanotrophs are often concentrated in a narrow range at the interface of and
in the water.

Question 48

Bacteria able to grow chemolithotrophically at the expense of reduced inorganic nitrogen compounds are called .

Question 49

Because of the rapid motility of Proteus cells, colonies growing on agar plates often exhibit a characteristic phenotype.

Question 50

Organisms that can grow using carbon compounds lacking C- C bonds are called methylotrophs.

Question 51

Some acetic acid bacteria can also synthesize the polymer from monomers.

Question 52

Members of the genus Vibrio are typically isolated from the mammalian intestinal tract.

Question 53

The gram- positive bacteria are a large group of primarily chemoorganotrophic Bacteria.

Question 54

The metal must be present in the medium for chemolithotrophic growth of hydrogen bacteria because virtually all hydrogenases contain the ion as a metal cofactor.

Question 55

Nitrifying bacteria develop particularly well in lakes and streams receiving sewage because of the ammonia (NH3) present in the sewage.

Question 56

constitute the majority of known bacteria of medical, industrial, and agricultural significance.

Question 57

The polarity of magnetic cells from the Southern Hemisphere is opposite the polarity of those from the Northern Hemisphere.

Question 58

The genus forms pigments called prodigiosins that are produced only during the
of growth and are metabolites.

Question 59

Proteobacteria are all gram- negative.

Question 60

Cysts, although similar to bacterial endospores in being resting structures, can rapidly oxidize substrates when exposed to them and are less resistant to than endospores.

Question 61

Pseudomonas pathogens affect only members of the animal kingdom.

Question 62

Nitrification occurs especially well in habitats where acids are present.

Question 63

Sulfur lithotrophs can grow either chemolithotrophically or chemoorganotrophically.

Question 64

Cytoplasmic extrusions can minimize sinking of aquatic bacteria that possess them.

Question 65

Bacteria within the genus Wolbachia can influence sexual differentiation in certain insects and amphibians.

Question 66

The epsilon proteobacterium Arcobacter nitrofigilis is often found in a parasitic relationship with the roots of the salt marsh cordgrass Spartina.

Question 67

Opportunistic pathogens are often referred to as protopathogens.

Question 68

Purple phototrophic bacteria are so diverse that they actually are present within the Alpha- , Beta- , and Gammaproteobacteria.

Question 69

Most bioluminescent bacteria are found in marine environments.

Question 70

All nitrifying bacteria are obligate chemolithotrophs and obligate aerobes.

Question 71

Explain the process of quorum sensing as it relates to regulation of bacterial bioluminescence in Vibrio fischeri.

Question 72

Explain the symbiotic relationship between the methanotrophic bacteria and certain marine mussels and sponges.

Question 73

The primary mode of transmission for a rickettsial disease is person- to- person contact.

Question 74

All methylotrophs are also methanotrophs.

Question 75

Methane oxidizers and ammonia oxidizers exhibit great similarity in the structure of their internal membrane systems and are phylogenetically closely related.

Question 76

Sterols are thought to be unique to autotrophic prokaryotes.

Question 77

Explain why many thiobacilli are acidophilic.

Question 78

No chemolithotroph is known to completely oxidize ammonia to nitrate.

Question 79

An identifying trait of the cell division cycle of Caulobacter is the absence of a motile stage.

Question 80

Organisms that attach to solid surfaces will grow in a very dilute nutrient solution.