GENE3200 – Summer 2010 – Bedell ID no. 810-________ KEY ______________ Quiz 6 – July 23 Bacterial cells of genotype pur – pro + his + were transduced with phage P1 (a generalized transducing phage) grown on bacteria of genotype pur + pro – his – . Transductants containing pur + were selected and tested for the unselected markers pro and his. The numbers of pur + colonies with each of four genotypes are as follows: pro + his + 114 pro + his – 160 pro – his + 25 pro – his – 1 A. (2 pts) What is the co-transduction frequency (as percentage of total transductants) for pur and pro? Show your calculation. (25 + 1)/300 x 100 = 8.7% B. (2 pts) What is the co-transduction frequency (as percentage of total transductants) for pur and his? Show your calculation. (160+1)/300 x 100 = 53.7% C. What is the gene order? Justify your answer . pur – his – pro pur – pro – his pro – pur – his Co transduction results indicate that pur is closer to his than it is to pro. So, this rules out
This is the end of the preview.
access the rest of the document.