mkw6d@krebs.acc.Virginia.EDU (Martyn K. White) (05/09/91)
We have been trying to isolate a chicken cDNA from a lambdaGT10 library using a rat cDNA homologue as a probe. A positive plaque was picked, the phage grown up, the lambda DNA isolated, the 3kb EcoRI insert fragment isolated and subcloned into pBS. Sequencing reactions from a miniprep were run from both ends and when run against genbank, it proved to be 99.7% homologous to E.coli RNA polymerase B!!?! Has anyone else experienced pulling out an E.coli gene like this? What might cause this? Our current hypothesis is that this is a subcloning artefact caused by contaminating E.coli genomic DNA in our lambda DNA prep and we are doing Southern blots with our rat probe and are screening more minipreps of the pBS ligation transformants to see what is going on. Comments welcome, thanks Martyn Martyn K. White, Box 441, U.Va, Cville VA 22908 (804) 924 8710 mkw6d@krebs.acc.Virginia.EDU mkw6d@Virginia.EDU