果胶裂解酶基因PelC表达载体的构建及原核表达分析

从实验室分离保存的1株产果胶酶的菌株（BTC105）中克隆果胶裂解酶基因（PelC）完整开放阅读框，通过载体构建，将目的基因连接到表达载体pET28a上，转化大肠埃希茵BL21（DE3）进行融合表达，在LB（Luria—Bertani）中进行摇瓶发酵，1mmol／LIPTG（异丙基－β－D－硫代半乳糖苷）诱导。结果表明，拘建了表达载俸pET28a－felC，果胶裂解酶主要在胞内表达，酶活最适pH为5．4，最适温度为50℃，Ca^2＋对酶活促进作用最为明显，Cu^2＋完全抑制了酶的活性。

Construction of Vector Harboring Pectin Lyase C Gene and Its Expression in E. coli

A complete open reading frame of pectin lyase C (PelC) cloned from a pectinase-producing strain BTC105 isolated and collected in the laboratory was constructed on a plasmid pET28a and transferred into E. coli BL21 (DE3) to carry out fuse expression; and flask shaking fermented in LB (Luria-Bertani) , induced with 1 mmol/L IPTG (iso-propyl β-D-1-thiogalactopyranoside). The results showed that the recombinant plasmid pET28a-pelC was constructed successfully and PelC has mainly expressed in E. coli BL21 (DE3). The optimal pH of the enzyme was 5.4, optimal temperature at 50℃, Ca~(2+) stimulated strongly on the enzyme activity, however, Cu~(2+) completely inhibited the activity.