Bakunina I Y, Sova V V, Nedashkovskaya O I, Kuhlmann R A, Likhosherstov L M, Martynova M D, Mihailov V V, Elyakova L A
Pacific Institute of Bioorganic Chemistry, Far Eastern Division of the Russian Academy of Sciences, Vladivostok, 690022, Russia.
Biochemistry (Mosc). 1998 Oct;63(10):1209-15.
An alpha-galactosidase that inactivates the group specificity of B erythrocytes (group III) of human blood and does not affect A erythrocytes (group II) was isolated from the marine bacterium Pseudoalteromonas sp. KMM 701. The enzyme preparation did not contain lectin, hemolytic, sialidase, endoglycanase, or glycosidase activities. The enzyme is stable at 20 degreesC for 24 h, has pH optimum for catalysis within the range of 6.7-7.7, and is stable to high concentrations of NaCl. It is 4-fold more efficient than the alpha-galactosidase from green coffee beans. At pH 7.0 the Km for p-nitrophenyl-alpha-D-galactopyranoside is 0.29 mM. The molecular weight of the enzyme determined by gel-filtration is 195 +/- 5 kD. The alpha-galactosidase is denatured by urea and guanidine hydrochloride. Its activity does not depend on the presence of metal ions. It contains a sulfhydryl group essential for its catalytic activity.
从海洋细菌假交替单胞菌属（Pseudoalteromonas sp.）KMM 701中分离出一种α-半乳糖苷酶，该酶可使人类血液中B型红细胞（III组）的基团特异性失活，而不影响A型红细胞（II组）。该酶制剂不含有凝集素、溶血、唾液酸酶、内切聚糖酶或糖苷酶活性。该酶在20℃下稳定24小时，催化作用的最适pH范围为6.7 - 7.7，对高浓度NaCl稳定。它比来自绿咖啡豆的α-半乳糖苷酶效率高4倍。在pH 7.0时，对硝基苯基-α-D-吡喃半乳糖苷的Km为0.29 mM。通过凝胶过滤测定的该酶分子量为195±5 kD。该α-半乳糖苷酶被尿素和盐酸胍变性。其活性不依赖于金属离子的存在。它含有一个对其催化活性至关重要的巯基。
