9.A.13 The Colicin J Lysis (Cjl) Family
The colicin J lysis peptide Cjl is 65 aas long. It has no homologues in the databases. It is encoded within an operon in Shigella sonneiwhich includes the cgl(ORF65) and cga(ORF94; colicin J) genes. No transmembrane helix (TMpred), no signal peptide, and no prokaryotic protein motif (PROSITE) was identified in Cjl. Cjl has been shown to promote selective colicin J release from producer bacteria (Smajs and Weinstock, 2001). It may do so initially by forming pores before inducing cell lysis. The cjlgene superficially resembles the kilgenes of some colicin plasmids coding for semispecific release of colicins from the producer bacteria. Expression of the kilgenes also results in cell lysis and is regulated by the promoter that controls colicin gene expression.
The presumed transport reaction catalyzed by the colicin J lysis (Cjl) protein is:
colicin J (in)Æ colicin J (out)