Jacobsen T, Poulsen O M
Department of Life Sciences and Chemistry, University of Roskilde, Denmark.
Biochim Biophys Acta. 1995 Jul 13;1257(2):96-102. doi: 10.1016/0005-2760(95)00059-l.
The type A lipase and the cis-9 18:1 specific type B lipase of different strains of Geotrichum candidum were compared. Comparing the enzyme activity of crude lipase preparation and purified type A and type B lipases and the protein pattern of these preparations in denaturing polyacrylamide gel electrophoresis (SDS-PAGE) revealed that the specific activity for cis-9 18:1 fatty acids was related to the content of the type B lipase. Tandem-crossed immunoelectrophoresis was used to demonstrate immunological identity between type A and type B lipase of G. candidum ATCC 66592. Partial immunological identity was observed between type B lipase of this strain and type A lipase of G. candidum ATCC 34614 and two commercial crude G. candidum lipase preparations (Amano and Biocatalyst), i.e., the type B lipase of G. candidum ATCC 66592 had immunogenic epitopes which are not present on the other lipases. Enzymatic deglycosylation of the lipases did not alter this pattern. After partial proteolysis of purified type A and type B lipases of G. candidum ATCC 66592, Amano and Biocatalyst, no difference between the type A lipase of the three strains was observed in SDS-PAGE. For all strains the type B lipase exhibited a distinctly different peptide pattern to that of the type A lipase. In addition, the type B lipase of G. candidum ATCC 66592 differed from the type B lipase of Amano and Biocatalyst by having an additional peptide band. The results indicate that the G. candidum ATCC 66592 should be considered a distinct strain regarding the protein chemical characteristics of its type B lipase, whereas the two commercial lipase preparations appear to be very similar.
对不同菌株的白地霉的 A 型脂肪酶和顺式-9 18:1 特异性 B 型脂肪酶进行了比较。比较粗脂肪酶制剂以及纯化的 A 型和 B 型脂肪酶的酶活性，以及这些制剂在变性聚丙烯酰胺凝胶电泳（SDS-PAGE）中的蛋白质图谱，结果表明顺式-9 18:1 脂肪酸的比活性与 B 型脂肪酶的含量有关。采用串联交叉免疫电泳来证明白地霉 ATCC 66592 的 A 型和 B 型脂肪酶之间的免疫同一性。观察到该菌株的 B 型脂肪酶与白地霉 ATCC 34614 的 A 型脂肪酶以及两种市售白地霉粗脂肪酶制剂（天野和生物催化剂）之间存在部分免疫同一性，即白地霉 ATCC 66592 的 B 型脂肪酶具有其他脂肪酶所没有的免疫原性表位。脂肪酶的酶促去糖基化并未改变这种模式。对白地霉 ATCC 66592、天野和生物催化剂的纯化 A 型和 B 型脂肪酶进行部分蛋白酶解后，在 SDS-PAGE 中未观察到这三个菌株的 A 型脂肪酶之间存在差异。对于所有菌株，B 型脂肪酶呈现出与 A 型脂肪酶明显不同的肽图谱。此外，白地霉 ATCC 66592 的 B 型脂肪酶与天野和生物催化剂的 B 型脂肪酶不同，它有一条额外的肽带。结果表明，就其 B 型脂肪酶的蛋白质化学特性而言，白地霉 ATCC 66592 应被视为一个独特的菌株，而两种市售脂肪酶制剂似乎非常相似。
