The nucleotide sequence of a bacteriocin-encoding plasmid isolated from Kle
bsiella pneumoniae (pKlebB-K17/80) has been determined. The encoded klebiei
n B protein is similar in sequence to the DNase pyocins and colicins, sugge
sting that klebiein B functions as a nonspecific endonuclease. The klebiein
gene cluster, as well as the plasmid backbone. is a chimera, with regions
similar to those of pore-former colicins, nuclease pyocins and colicins as
well as noncolicinogenic plasmids. Similarities between pKlebB plasmid main
tenance functions and those of the colicin El plasmid suggest that pKlebB i
s a member of the ColE1 plasmid replication family. (C) 2001 Academic Press