title: Purification and Characterization of a New Alginate Lyase from Marine Bacterium Vibrio sp. SY08.
abstract: Unsaturated alginate disaccharides (UADs), enzymatically derived from the degradation of alginate polymers, are considered powerful antioxidants. In this study, a new high UAD-producing alginate lyase, AlySY08, has been purified from the marine bacteriumVibriosp. SY08. AlySY08, with a molecular weight of about 33 kDa and a specific activity of 1070.2 U/mg, showed the highest activity at 40 °C in phosphate buffer at pH 7.6. The enzyme was stable over a broad pH range (6.0-9.0) and retained about 75% activity after incubation at 40 °C for 2 h. Moreover, the enzyme was active in the absence of salt ions and its activity was enhanced by the addition of NaCl and KCl. AlySY08 resulted in an endo-type alginate lyase that degrades both polyM and polyG blocks, yielding UADs as the main product (81.4% of total products). All these features made AlySY08 a promising candidate for industrial applications in the production of antioxidants from alginate polysaccharides.
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. lshywln@163.com.
authors.forename: Shangyong
authors.initials: S
authors.lastname: Li
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. wlnwfllsy@163.com.
authors.forename: Linna
authors.initials: L
authors.lastname: Wang
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. haojh@ysfri.ac.cn.|Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China. haojh@ysfri.ac.cn.
authors.forename: Jianhua
authors.initials: J
authors.lastname: Hao
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. 15865506157@126.com.
authors.forename: Mengxin
authors.initials: M
authors.lastname: Xing
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. sunjj@ysfri.ac.cn.
authors.forename: Jingjing
authors.initials: J
authors.lastname: Sun
authors.affiliation: Key Laboratory of Sustainable Development of Marine Fisheries, Ministry of Agriculture, Yellow Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, 106 Nanjing Road, Qingdao 266071, China. sunmi0532@yahoo.com.|Laboratory for Marine Drugs and Bioproducts, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China. sunmi0532@yahoo.com.
authors.forename: Mi
authors.initials: M
authors.lastname: Sun
mesh_terms: D000464:Alginates / Q000737:chemistry*; D059001:Aquatic Organisms / Q000737:chemistry*; D004795:Enzyme Stability; D020723:Glucuronic Acid / Q000737:chemistry; D006603:Hexuronic Acids / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D008970:Molecular Weight; D011133:Polysaccharide-Lyases / Q000737:chemistry*; D012965:Sodium Chloride / Q000737:chemistry; D013379:Substrate Specificity; D013696:Temperature; D014733:Vibrio / Q000737:chemistry*
chemical_list: D000464:Alginates; D006603:Hexuronic Acids; D012965:Sodium Chloride; D020723:Glucuronic Acid; D011133:Polysaccharide-Lyases; C016158:poly(beta-D-mannuronate) lyase
keywords: Vibrio sp.; alginate lyase; thermostability; unsaturated alginate disaccharides