Nucleotide sequence of the immunity region of bacteriophage Mu

Abstract

The leftmost 1590 bp of Mu DNA covering the immunity region have been sequenced. This region encodes thecI repressor, thecII orner function and the beginning of geneA. An open reading frame extends from position 863 to 342 on the l-strand corresponding tocI protein with a molecular weight of 19212. It is preceeded by a sequence resembling a promoter. To the right of theHindIII site an open reading frame extends from position 1099 to 1323 corresponding tocII orner protein (molecular weight of 8505) followed by the beginning of geneA at position 1328. Between position 863 and 1099 promoters for leftward and rightward transcription and operator-like structures can be recognized in the sequence. The promoter for rightward transcription overlaps with theHindIII site and coincides with a RNA polymerase binding site as demonstrated by electron microscopy.