Identification of the J and K genes in the bacteriophage Mu genome sequence.

Bacteriophage Mu was the first transposable phage to be discovered and still serves as the model for a large family of related transposable phages and prophages. The Mu genome sequence is known (NC-000929.1 GI:9633494), but not all of the genes have been assigned to the ORFs in the genome sequence. For this paper, we have sequenced an approximately 3-kb DNA region containing four predicted ORFs, Mup35-Mup38, from lysogens containing amber mutant prophages defective in either the J or the K gene. Amber mutations in prophages with J gene mutations mapped to the Mup36 ORF, and those in the K gene were found in Mup37, identifying the ORFs corresponding to these genes.