title: Molecular cloning, characterization, and heterologous expression of a new κ-carrageenase gene from marine bacterium Zobellia sp. ZM-2.
abstract: κ-Carrageenases exhibit apparent distinctions in gene sequence, molecular weight, enzyme properties, and posttranslational processes. In this study, a new κ-carrageenase gene named cgkZ was cloned from the marine bacterium Zobellia sp. ZM-2. The gene comprised an open reading frame of 1,638 bp and encoded 545 amino acids. The natural signal peptide of κ-carrageenase was used successfully for the secretory production of the recombinant enzyme in Escherichia coli. A posttranslational process that removes an amino acid sequence of about 20 kDa from the C-terminal end of κ-carrageenase was first discovered in E. coli. An increase in enzyme activity by 167.3% in the presence of 5 mM DTT was discovered, and Na(+) at a certain concentration range was positively correlated with enzyme activity. The κ-carrageenase production of E. coli was 9.0 times higher than that of ZM-2. These results indicate the potential use of the enzyme in the biotechnological industry.
authors.affiliation: College of Food Science and Engineering, Ocean University of China, Qingdao, 266003, China.
authors.forename: Zhemin
authors.initials: Z
authors.lastname: Liu
authors.forename: Guiyang
authors.initials: G
authors.lastname: Li
authors.forename: Zhaolan
authors.initials: Z
authors.lastname: Mo
authors.forename: Haijin
authors.initials: H
authors.lastname: Mou
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D003001:Cloning, Molecular; D004795:Enzyme Stability; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005285:Fermentation; D041965:Flavobacteriaceae / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification; D015870:Gene Expression; D006026:Glycoside Hydrolases / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010802:Phylogeny; D021382:Protein Sorting Signals; D012623:Seawater / Q000382:microbiology*; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D021382:Protein Sorting Signals; D006026:Glycoside Hydrolases