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Eubacteria that lack cell walls and do not synthesize the precursors of peptidoglycan are called
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(A) Gram-negative bacteria
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Archaebacteria can be distinguished from eubacteria by their lack of
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A 16-year-old cystic fibrosis patient is admitted to the hospital. A sputum culture yields Burkholderia cepacia. Subsequently, there are two other patients with B cepacia bacteremia, and the organism is cultured from the sputum of four additional patients. During this nosocomial outbreak of B cepacia, 50 environmental and 7 patient isolates are being subtyped to identify the source of the outbreak. Which of the following techniques would be most useful in this endeavor?
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(D) Antimicrobial susceptibility testing
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(E) Nucleic acid sequencing
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An unculturable gram-positive microorganism has been visualized in tissue specimens obtained from patients with a previously undescribed disease. Which of the following techniques would be most useful in identifying this organism?
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(B) PCR amplification and sequencing of rRNA genes
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(C) Multilocus enzyme electrophoresis
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(D) SDS-polyacrylamide gel electrophoresis
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(E) Pulsed field gel electrophoresis
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The DNA polymerase from Thermus aquaticus is an important component of DNA amplification methods such as the polymerase chain reaction. This organism is capable of growing at temperatures above 100°C. Organisms that are capable of growth at these temperatures are referred to as
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A bacteria with a genome having a G + C content of 45% harbors a plasmid encoding a gene with a G + C content of 55%. Which one of the following conclusion could be drawn?
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(A) This gene codes for a cell wall peptidyl transferase
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(B) This gene codes for a critical bacterial cytochrome
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(C) This gene codes for a unique transfer RNA
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(D) This gene codes for a plasmid RNA-dependent DNA-polymerase
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(E) This gene codes for an antigenically diverse capsular polysaccharide