title: A novel esterase from Paenibacillus sp. PBS-2 is a new member of the β-lactamase belonging to the family VIII lipases/esterases.
abstract: Screening of a gene library from Paenibacillus sp. PBS-2 generated in Escherichia coli led to the identification of a clone with lipolytic activity. Sequence analysis showed an open reading frame encoding a polypeptide of 378 amino acid residues with a predicted molecular mass of 42 kDa. The esterase displayed 69% and 42% identity with the putative β-lactamases from Paenibacillus sp. JDR-2 and Clostridium sp. BNL1100, respectively. The esterase contained a Serx- x-Lys motif that is conserved among all β-lactamases found to date. The protein PBS-2 was produced in both soluble and insoluble forms when E. coli cells harboring the gene were cultured at 18°C. The enzyme is a serine protein and was active against p-nitrophenyl esters of C2, C4, C8, and C10. The optimum pH and temperature for enzyme activity were pH 9.0 and 30°C, respectively. Relative activity of 55% remained at up to 5°C with an activation energy of 5.84 kcal/mol, which indicates that the enzyme is cold-adapted. Enzyme activity was inhibited by Cd(2+), Cu(2+), and Hg(2+) ions. As expected for a serine esterase, activity was inhibited by phenylmethylsulfonyl fluoride. The enzyme was remarkably active and stable in the presence of commercial detergents and organic solvents. This cold-adapted esterase has potential as a biocatalyst and detergent additive for use at low temperatures.
authors.affiliation: Biotechnology Research Division, National Fisheries Research and Development Institute, Busan 619-705, Republic of Korea.
authors.forename: Young-Ok
authors.initials: YO
authors.lastname: Kim
authors.forename: In-Suk
authors.initials: IS
authors.lastname: Park
authors.forename: Bo-Hye
authors.initials: BH
authors.lastname: Nam
authors.forename: Dong-Gyun
authors.initials: DG
authors.lastname: Kim
authors.forename: Young-Ju
authors.initials: YJ
authors.lastname: Jee
authors.forename: Sang-Jun
authors.initials: SJ
authors.lastname: Lee
authors.forename: Cheul-Min
authors.initials: CM
authors.lastname: An
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D001483:Base Sequence; D003902:Detergents / Q000737:chemistry; D004795:Enzyme Stability; D004950:Esterases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D008670:Metals / Q000737:chemistry; D008969:Molecular Sequence Data; D009930:Organic Chemicals / Q000737:chemistry; D056507:Paenibacillus / Q000201:enzymology* / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D016415:Sequence Alignment; D013696:Temperature; D001618:beta-Lactamases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D047090:beta-Lactams / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D003902:Detergents; D008670:Metals; D009930:Organic Chemicals; D011994:Recombinant Proteins; D047090:beta-Lactams; D004950:Esterases; D001618:beta-Lactamases