When λ λλ λ P P P – –– :: : infects a wild type (Su – Kan s ) E. coli host, the phage DNA can not replicate ( PPPPP ) nor can it integrate ( i –– ) thus the only way for the E. coli to become Kan r is for TTTTT to transpose from the λ DNA to some location on the E. coli chromosome. This type of transposition is an inherently rare process and will occur in about one out of 10 5 phage-infected E. coli cells. This is how a transposon mutagenesis might be done: 1) Infect 2x10 9 wild-type E. coli cells with λ P – : so that each cell receives at least one phage chromosome. 2) Select for Kan r by plating on medium that contains kanamycin. There should be a total of about
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This note was uploaded on 11/05/2011 for the course BIOLOGY MCB2010 taught by Professor Jessicadigirolamo during the Fall '10 term at Broward College.