title: Heterologous expression and characterization of a recombinant thermostable alkylsulfatase (sdsAP).
abstract: A novel alkylsulfatase gene, sdsAP, was cloned from a newly isolated bacterium Pseudomonas sp. S9. It encoded a protein of 675 amino acids with a calculated molecular mass of 74.9 kDa. The protein contained a typical N-terminal signal peptide of 41 amino acid residues, followed by a metallo-β-lactamase like domain at the N-terminus and a SCP-2-like domain at the C-terminus. This domain organization mode suggested that it belonged to the type III sulfatase. The mature alkylsulfatase was overexpressed in Escherichia coli. The optimal temperature and pH of the recombinant SdsAP were 70°C and 9.0, respectively. Notably, at optimal conditions, the purified recombinant SdsAP had a high specific activity of 23.25 μmol min(-1) mg(-1), a K(m (app)) of 264.3 μmol, and a V(max (app)) of 33.8 μmol min(-1) mg(-1) for SDS. Additionally, it still retained more than 90% activity after incubation at 65°C for 1 h, which was much different from other alkylsulfatases reported. The recombinant enzyme hydrolyzed the primary alkyl sulfate such as sodium octyl sulfate and sodium dodecyl sulfate (SDS). It was a Zn(2+)-containing and Ca(2+) activated alkylsulfatase. This is the first report to explore the various characteristics of the heterologous recombinant alkylsulfatase in details. These favorable properties could make SdsAP attractive to be useful in the degradation of SDS-containing waste.
authors.affiliation: State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, 430070 Wuhan, Hubei, People's Republic of China. longmengxian@126.com
authors.forename: Mengxian
authors.initials: M
authors.lastname: Long
authors.forename: Lingwei
authors.initials: L
authors.lastname: Ruan
authors.forename: Fuying
authors.initials: F
authors.lastname: Li
authors.forename: Ziniu
authors.initials: Z
authors.lastname: Yu
authors.forename: Xun
authors.initials: X
authors.lastname: Xu
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D002118:Calcium / Q000737:chemistry; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D015971:Gene Expression Regulation, Enzymologic; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D011549:Pseudomonas / Q000201:enzymology; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D013429:Sulfatases / Q000737:chemistry* / Q000378:metabolism; D013696:Temperature; D015032:Zinc / Q000737:chemistry
chemical_list: D012336:RNA, Ribosomal, 16S; D011994:Recombinant Proteins; D012967:Sodium Dodecyl Sulfate; D013429:Sulfatases; C019244:alkylsulfatase; D015032:Zinc; D002118:Calcium