Abstract: Klebsiella pneumoniae causes neonatal sepsis and nosocomial infections. One of the strains, K. pneumoniae MGH 78578, shows high level of resistance to multiple microbial agents. In this study, domain family, amino acid sequence and topology analyses were performed on one of its hypothetical protein, YggG (KPN_03358). Structural bioinformatics approaches were used to predict the structure and functionality of YggG protein. The open reading frame (ORF) of yggG, which was a putative metalloprotease gene, was also cloned, expressed and characterized. The ORF was PCR amplified from K. pneumoniae MGH 78578 genomic DNA and cloned into a pET14-b vector for heterologous expression in Escherichia coli. The purified YggG protein was subsequently assayed for casein hydrolysis under different conditions. This protein was classified as peptidase M48 family and subclan gluzincin. It was predicted to contain one transmembrane domain by TMpred. Optimal protein expression was achieved by induction with 0.6 mM isopropyl thiogalactoside (IPTG) at 25 °C for six hours. YggG was purified as soluble protein and confirmed to be proteolytically active under the presence of 1.25 mM zinc acetate and showed optimum activity at 37 °C and pH 7.4. We confirmed for the first time that the yggG gene product is a zinc-dependent metalloprotease.
This is an open access article distributed under the
Creative Commons Attribution License which permits unrestricted use, distribution,
and reproduction in any medium, provided the original work is properly cited.
Export to BibTeX
MDPI and ACS Style
Kuan, C.S.; Wong, M.T.; Choi, S.B.; Chang, C.C.; Yee, Y.H.; Wahab, H.A.; Normi, Y.M.; Too, W.C.S.; Few, L.L. Klebsiella pneumoniae yggG Gene Product: A Zinc-Dependent Metalloprotease. Int. J. Mol. Sci. 2011, 12, 4441-4455.
Kuan CS, Wong MT, Choi SB, Chang CC, Yee YH, Wahab HA, Normi YM, Too WCS, Few LL. Klebsiella pneumoniae yggG Gene Product: A Zinc-Dependent Metalloprotease. International Journal of Molecular Sciences. 2011; 12(7):4441-4455.
Kuan, Chee Sian; Wong, Mun Teng; Choi, Sy Bing; Chang, Ching Ching; Yee, Yoke Hiang; Wahab, Habibah A.; Normi, Yahaya Mohd; Too, Wei Cun See; Few, Ling Ling. 2011. "Klebsiella pneumoniae yggG Gene Product: A Zinc-Dependent Metalloprotease." Int. J. Mol. Sci. 12, no. 7: 4441-4455.