Bioinformatic Analysis of a Grimelysin-like Protease in the Klebsiella oxytoca Strain NK-1

Bacterial intracellular proteinases play a relevant role in coordinating various cellular processes. The genome of the uropathogenic Klebsiella oxytoca NK-1 encodes the gene prtKO , homologous to grimelysin of Serratia grimesii . BLAST analysis showed that a lot of bacteria encode grimelysin-like proteinases, known to be mainly distributed in Enterobacterales . Phylogenetic analysis classified these proteins into 10 clusters. PrtKO was predicted to contain conservative motifs typical for grimelysin using bioinformatic tools. In addition, the structure of metalloproteinase-containing genomic loci is conservative among enterobacteria and consists of the genes involved in global physiological processes. Maximal total intracellular proteolytic activity of K. oxytoca NK-1 is observed during the late stationary phase of growth in LB medium at 37 °C. Limited proteolysis of actin indicates the presence of a grimelysin-like proteinase in bacterial cells during the late stationary growth phase. Hence, we present a first report of a new grimelysin-like intracellular metalloproteinase in K. oxytoca .