CLONING AND EXPRESSION OF THE HUP GENE ENCODING A HISTONE-LIKE PROTEIN OF CAMPYLOBACTER-JEJUNI

A Campylobacter jejuni gene, designated hup, that appears to encode a homolog of the histone-like DNA-binding protein, HU, has been cloned, sequenced and expressed in Escherichia coli. Immunoblotting and in vit ro transcription/translation analyses revealed a 11-kDa protein that w as produced by recombinant plasmids containing hup. The gene contains an open reading frame (ORF) sufficient to encode a protein of 98 amino acids (aa) with a calculated molecular mass of 10 267 Da and a predic ted isoelectric point of 10.1. The deduced aa sequence of the protein, designated HCj, exhibits considerable sequence identity with members of the HU family of proteins from other eubacterial species. The trans cription start point was identified by primer extension analysis and a ppropriately spaced promoter sequences were found which exhibit consid erable similarity to E. coli and Bacillus promoters. Southern hybridiz ation analyses indicate that C. jejuni has a single copy of hup.