{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,3]],"date-time":"2026-04-03T16:04:49Z","timestamp":1775232289273,"version":"3.50.1"},"reference-count":41,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2011,7,7]],"date-time":"2011-07-07T00:00:00Z","timestamp":1309996800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>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 \u00b0C 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 \u00b0C and pH 7.4. We confirmed for the first time that the yggG gene product is a zinc-dependent metalloprotease.<\/jats:p>","DOI":"10.3390\/ijms12074441","type":"journal-article","created":{"date-parts":[[2011,7,7]],"date-time":"2011-07-07T10:36:02Z","timestamp":1310034962000},"page":"4441-4455","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Klebsiella pneumoniae yggG Gene Product: A Zinc-Dependent Metalloprotease"],"prefix":"10.3390","volume":"12","author":[{"given":"Chee Sian","family":"Kuan","sequence":"first","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mun Teng","family":"Wong","sequence":"additional","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sy Bing","family":"Choi","sequence":"additional","affiliation":[{"name":"Pharmaceutical Design and Simulation (PhDS) Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ching Ching","family":"Chang","sequence":"additional","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoke Hiang","family":"Yee","sequence":"additional","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Habibah A.","family":"Wahab","sequence":"additional","affiliation":[{"name":"Pharmaceutical Design and Simulation (PhDS) Laboratory, School of Pharmaceutical Sciences, Universiti Sains Malaysia, 11800 Minden, Pulau Pinang, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yahaya Mohd","family":"Normi","sequence":"additional","affiliation":[{"name":"Department of Cell and Molecular Biology, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 Serdang, Selangor, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wei Cun See","family":"Too","sequence":"additional","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ling Ling","family":"Few","sequence":"additional","affiliation":[{"name":"School of Health Sciences, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2011,7,7]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"28","DOI":"10.1016\/S0188-4409(99)00083-1","article-title":"Klebsiella pneumoniae 35 and 36 kDa porins are common antigens in different serotypes and induce opsonizing antibodies","volume":"31","author":"Santos","year":"2000","journal-title":"Arch. Med. Res"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1588","DOI":"10.1378\/chest.114.6.1588","article-title":"Etiology of community-acquired pneumonia in hospitalized patients: A 3-year prospective study in Japan","volume":"114","author":"Ishida","year":"1998","journal-title":"Chest"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1016\/0195-6701(94)90117-1","article-title":"Klebsiella bacteraemia: A report of 101 cases from National University Hospital, Singapore","volume":"27","author":"Lee","year":"1994","journal-title":"J. Hosp. Infect"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"135","DOI":"10.1017\/S0950268897007930","article-title":"Klebsiella meningitis in Taiwan: An overview","volume":"119","author":"Tang","year":"1997","journal-title":"Epidemiol. Infect"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"160","DOI":"10.3201\/eid0802.010025","article-title":"Community-acquired Klebsiella pneumoniae bacteremia: global differences in clinical patterns","volume":"8","author":"Ko","year":"2002","journal-title":"Emerg. Infect. Dis"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"1505","DOI":"10.1248\/bpb.28.1505","article-title":"Multidrug resistance in Klebsiella pneumoniae MGH78578 and cloning of genes responsible for the resistance","volume":"28","author":"Ogawa","year":"2005","journal-title":"Biol. Pharm. Bull"},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"136","DOI":"10.1186\/1471-2105-10-136","article-title":"Infrastructure for the life sciences: design and implementation of the UniProt website","volume":"10","author":"Jain","year":"2009","journal-title":"BMC Bioinform"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"D355","DOI":"10.1093\/nar\/gkp896","article-title":"KEGG for representation and analysis of molecular networks involving diseases and drugs","volume":"38","author":"Kanehisa","year":"2010","journal-title":"Nucleic Acids Res"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"91","DOI":"10.1016\/S1286-4579(00)00280-X","article-title":"Microbial metalloproteases and pathogenesis","volume":"2","author":"Miyoshi","year":"2000","journal-title":"Microbes. Infect"},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"736","DOI":"10.1128\/iai.51.3.736-743.1986","article-title":"Purification and characterization of an extracellular protease of Legionella pneumophila","volume":"51","author":"Dreyfus","year":"1986","journal-title":"Infect. Immun"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"3311","DOI":"10.1128\/jb.173.11.3311-3317.1991","article-title":"Cloning and nucleotide sequence of the Vibrio cholerae hemagglutinin\/protease (HA\/protease) gene and construction of an HA\/protease-negative strain","volume":"173","author":"Hase","year":"1991","journal-title":"J. Bacteriol"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1202","DOI":"10.1128\/IAI.68.3.1202-1206.2000","article-title":"Metalloprotease activity in a small heat shock protein of the human malaria parasite Plasmodium vivax","volume":"68","author":"Fakruddin","year":"2000","journal-title":"Infect. Immun"},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"758","DOI":"10.1128\/jb.174.3.758-764.1992","article-title":"Influence of cyclic AMP, agmatine, and a novel protein encoded by a flanking gene on speB (agmatine ureohydrolase) in Escherichia coli","volume":"174","author":"Szumanski","year":"1992","journal-title":"J. Bacteriol"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"8","DOI":"10.1111\/j.1574-6968.2007.00860.x","article-title":"Up-regulation of yggG promotes the survival of Escherichia coli cells containing era-1 mutant protein","volume":"275","author":"Huang","year":"2007","journal-title":"FEMS Microbiol. Lett"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"14","DOI":"10.1007\/s00284-007-9030-7","article-title":"Expression and regulation of the yggG gene of Escherichia coli","volume":"56","author":"Huang","year":"2008","journal-title":"Curr. Microbiol"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"525","DOI":"10.1007\/s10529-008-9906-z","article-title":"Introduction of a stress-responsive gene, yggG, enhances the yield of l-phenylalanine with decreased acetic acid production in a recombinant Escherichia coli","volume":"31","author":"Ojima","year":"2009","journal-title":"Biotechnol. Lett"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"183","DOI":"10.1016\/0076-6879(95)48015-3","article-title":"Evolutionary families of metallopeptidases","volume":"248","author":"Rawlings","year":"1995","journal-title":"Methods Enzymol"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"18","DOI":"10.1016\/S1046-5928(03)00188-8","article-title":"Overexpression and purification of recombinant membrane PsbH protein in Escherichia coli","volume":"32","author":"Halbhuber","year":"2003","journal-title":"Protein Expr. Purif"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"539","DOI":"10.1016\/j.jbbm.2006.12.002","article-title":"Expression and purification of HtpX-like small heat shock integral membrane protease of an unknown organism related to Methylobacillus flagellatus","volume":"70","author":"Siddiqui","year":"2007","journal-title":"J. Biochem. Biophys. Methods"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"283","DOI":"10.1107\/S0021889892009944","article-title":"Procheck\u2014a Program to Check the Stereochemical Quality of Protein Structures","volume":"26","author":"Laskowski","year":"1993","journal-title":"J. Appl. Cryst"},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/0263-7855(96)00018-5","article-title":"VMD: visual molecular dynamics","volume":"14","author":"Humphrey","year":"1996","journal-title":"J. Mol. Graph"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"2944","DOI":"10.1128\/jb.173.9.2944-2953.1991","article-title":"Isolation, characterization, and sequence of an Escherichia coli heat shock gene, htpX","volume":"173","author":"Kornitzer","year":"1991","journal-title":"J. Bacteriol"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"33305","DOI":"10.1074\/jbc.M506180200","article-title":"Proteolytic activity of HtpX, a membrane-bound and stress-controlled protease from Escherichia coli","volume":"280","author":"Sakoh","year":"2005","journal-title":"J. Biol. Chem"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"378","DOI":"10.1093\/bioinformatics\/14.4.378","article-title":"SOSUI: Classification and secondary structure prediction system for membrane proteins","volume":"14","author":"Hirokawa","year":"1998","journal-title":"Bioinformatics"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"849","DOI":"10.1093\/bioinformatics\/17.9.849","article-title":"The HMMTOP transmembrane topology prediction server","volume":"17","author":"Tusnady","year":"2001","journal-title":"Bioinformatics"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"489","DOI":"10.1006\/jmbi.1998.2107","article-title":"Principles governing amino acid composition of integral membrane proteins: application to topology prediction","volume":"283","author":"Tusnady","year":"1998","journal-title":"J. Mol. Biol"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"567","DOI":"10.1006\/jmbi.2000.4315","article-title":"Predicting transmembrane protein topology with a hidden Markov model: application to complete genomes","volume":"305","author":"Krogh","year":"2001","journal-title":"J. Mol. Biol"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"147","DOI":"10.1016\/S0968-0004(99)01540-6","article-title":"NPS@: Network protein sequence analysis","volume":"25","author":"Combet","year":"2000","journal-title":"Trends Biochem. Sci"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1083\/jcb.136.2.271","article-title":"A novel membrane-associated metalloprotease, Ste24p, is required for the first step of NH2-terminal processing of the yeast a-factor precursor","volume":"136","author":"Nouvet","year":"1997","journal-title":"J. Cell Biol"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"653","DOI":"10.1046\/j.1365-2443.2002.00554.x","article-title":"The Cpx stress response system of Escherichia coli senses plasma membrane proteins and controls HtpX, a membrane protease with a cytosolic active site","volume":"7","author":"Shimohata","year":"2002","journal-title":"Genes Cells"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"355","DOI":"10.1042\/BJ20070363","article-title":"Identification, cloning, expression and functional characterization of an astacin-like metalloprotease toxin from Loxosceles intermedia (brown spider) venom","volume":"406","author":"Wille","year":"2007","journal-title":"Biochem. J"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"101","DOI":"10.1016\/j.molbiopara.2010.07.004","article-title":"Cloning, characterisation and heterologous expression of an astacin metalloprotease, Sc-AST, from the entomoparasitic nematode Steinernema carpocapsae","volume":"174","author":"Jing","year":"2010","journal-title":"Mol. Biochem. Parasitol"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Polaina, J, and MacCabe, AP (2007). Industrial Enzymes: Structure, Function and Applications, Springer.","DOI":"10.1007\/1-4020-5377-0"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"e1000141","DOI":"10.1371\/journal.pgen.1000141","article-title":"Complete genome sequence of the N2-fixing broad host range endophyte Klebsiella pneumoniae 342 and virulence predictions verified in mice","volume":"4","author":"Fouts","year":"2008","journal-title":"PLoS Genet"},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"4492","DOI":"10.1128\/JB.00315-09","article-title":"Genome sequencing and comparative analysis of Klebsiella pneumoniae NTUH-K2044, a strain causing liver abscess and meningitis","volume":"191","author":"Wu","year":"2009","journal-title":"J. Bacteriol"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"779","DOI":"10.1006\/jmbi.1993.1626","article-title":"Comparative protein modelling by satisfaction of spatial restraints","volume":"234","author":"Sali","year":"1993","journal-title":"J. Mol. Biol"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"D211","DOI":"10.1093\/nar\/gkp985","article-title":"The Pfam protein families database","volume":"38","author":"Finn","year":"2010","journal-title":"Nucleic Acids Res"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"2947","DOI":"10.1093\/bioinformatics\/btm404","article-title":"Clustal W and Clustal X version 2.0","volume":"23","author":"Larkin","year":"2007","journal-title":"Bioinformatics"},{"key":"ref_39","first-page":"166","article-title":"Tmbase\u2014A database of membrane spanning protein segments","volume":"374","author":"Hofmann","year":"1993","journal-title":"Biol. Chem. Hoppe-Seyler"},{"key":"ref_40","doi-asserted-by":"crossref","unstructured":"Edwards, D, Hoyer-Hansen, G, Blasi, F, and Sloane, BF (2008). The Cancer Degradome, Springer Science + Business Media, LLC.","DOI":"10.1007\/978-0-387-69057-5"},{"key":"ref_41","doi-asserted-by":"crossref","unstructured":"Walters, S, Belanger, M, Rodrigues, P, Whitlock, J, and Progulske-Fos, A (2009). A member of the peptidase M48 superfamily of Porphyromonas gingivalis is associated with virulence in vitro andin vivo. J Oral Microbiol, 1.","DOI":"10.3402\/jom.v1i0.2021"}],"container-title":["International Journal of Molecular Sciences"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1422-0067\/12\/7\/4441\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:56:41Z","timestamp":1760219801000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1422-0067\/12\/7\/4441"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2011,7,7]]},"references-count":41,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2011,7]]}},"alternative-id":["ijms12074441"],"URL":"https:\/\/doi.org\/10.3390\/ijms12074441","relation":{},"ISSN":["1422-0067"],"issn-type":[{"value":"1422-0067","type":"electronic"}],"subject":[],"published":{"date-parts":[[2011,7,7]]}}}