You want to find E. coli genes necessary for lactate metabolism. You have a population of mutagenized E. coli. Which screening protocol would you use to find mutations in genes necessary for lactate metabolism? First plate on lactate media, then replicate plate on galactose media None of the options are correct Look for mutants that constitutively express lactate-metabolizing enzymes Plate directly on lactate media First plate on galactose media, then replicate plate on lactate media

You want to find E. coli genes necessary for lactate metabolism. You have a population of mutagenized E. coli. Which screening protocol would you use to find mutations in genes necessary for lactate metabolism? First plate on lactate media, then replicate plate on galactose media None of the options are correct Look for mutants that constitutively express lactate-metabolizing enzymes Plate directly on lactate media First plate on galactose media, then replicate plate on lactate media

Biology: The Dynamic Science (MindTap Course List)

4th Edition

ISBN:9781305389892

Author:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Publisher:Peter J. Russell, Paul E. Hertz, Beverly McMillan

Chapter17: Bacterial And Viral Genetics

Section: Chapter Questions

Problem 1ITD

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A research group is studying a bacterium X that binds to mucosal cells in the lung and invades. Wildtype X has an LD50 value of 10 bacteria when administered to mice by inhalation. Using transposon mutagenesis, the researchers have isolated two mutants of X that they call Xmut1 and Xmut2, both of which have LD50 values of 105 when inhaled by mice. However, in tissue culture cells, Xmut1 can invade the cells just as well as wild-type X, while Xmut2 cannot. Provide a possible explanation for these results.
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. In two isolates (one is resistant to ampicillin and theother is sensitive to ampicillin) of a new bacterium,you found that genes encoding ampicillin resistanceare being transferred into the sensitive strain. . To determine if the gene transfer is transformationor transduction, you treat the mixed culture of cellswith DNase. Why would this treatment distinguishbetween these two modes of gene transfer? Describethe results predicted if the gene transfer is transformation versus transduction
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