Exam 15: Diversity of Bacteria

Due to the genetic similarities of non-pathogenic and pathogenic enterics,phenotypic assays are often performed in favor over taxonomy-based sequencing/probing to distinguish pathogens from non-pathogens.

Many Listeria spp.grow well at cold temperatures,so although refrigeration is excellent at preventing growth of most other pathogens,it is not very useful at minimizing growth of contaminated foods.

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?

The enteric bacteria are a group classified within Proteobacteria that cause disease in animals.

Which genus is MOST easily distinguishable from others below by occurring in packets of 8 or more?

What would MOST likely result if an exponentially growing culture of Lactobacillus sp.fermenting glucose was accidentally transferred into a highly aerated environment?

Due to the slow and varied growth rates,mycobacteria are commonly grouped into either slow growing or very slow growing,which has consequences on the growth medium selected for culturing.

A yogurt,which had "contains live cultures" on its label,was transferred onto an acidic carbohydrate-containing medium for selective enrichment.Eventually,isolates of the ________ genus were obtained.

A soil sample was diluted into a nutrient broth,then spread onto a plate and grown for one week at room temperature.Several colonies appeared dusty or fuzzy and yet were identified as bacteria-not as fungi.Which genus do these isolates likely belong in?

When looking under a transmission electron microscope,you observe anammoxosomes in one bacterium and pirellulosome in another bacterium.BOTH taxa are likely a part of Planctomycetes.

Biosynthesis of vitamin K (menaquinone)by ________ spp.inhabiting the ________ of humans is a potentially important mutualistic relationship for human health.

Simple staining and microscopy could easily distinguish the different taxa intermixed within a community of Sarcina,Staphylococcus,and coryneform bacteria.

The ability to form endospores in bacteria within Bacillales,Clostridiales,and Lactobacillales suggests the genotype/phenotype evolved

Group members of ________ are particularly abundant in the oceans,chemoorganotrophic,and often produce pigments when grown on complex media.

Which group in Bacteria lacks cell walls?

Explain how the enteric bacteria can be differentiated by the type and proportion of fermentation products produced by the anaerobic fermentation of glucose.

Which of the following is LEAST commonly associated with endospore-forming bacteria?

Which organisms would MOST likely be isolated from aerobic growth conditions with acetate and a soil sample heated to 80°C for 10 min?

Which species does NOT produce endospores?

A moistened swab rubbed onto a person's forearm then onto a nutrient agar plate with 7.5% NaCl would MOST likely result in the isolation of ________ spp.