What is the length of the kanamycin cassette in the Keio collection ?

06 August 2021 1 552 Report

I need this information to verify the recA deletion strain JW2669. PCR with the flanking primers gives a band at 1.3 kb which I suppose contains the cassette. Ideally, I'd like to know where the Kanamycin cassette is coming from.

In addition, my PCR also gives a fainter band at 1.1 kb which, quite surprisingly, is the same size as the one expected and observed in the WT control. Does this mean my mutant is not a mutant and that the main PCR product comes from an artefact ?

Olivier Vallon

My question was a bit dum sorry: the paper indicates that they use pKD13 as the template, so the cassette is 1.3 kb and my PCR should give the 1.4 kb product I see. But the more interesting part remains unanswered: why do I see a band at the length of the WT product?...

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