Alfano J R, Ham J H, Collmer A
Department of Plant Pathology, Cornell University, Ithaca, New York 14853-4203, USA.
J Bacteriol. 1995 Aug;177(15):4553-6. doi: 10.1128/jb.177.15.4553-4556.1995.
Erwinia chrysanthemi mutant CUCPB5047, delta(pelA pelE) delta(pelB pelC)::28bp delta(pelX) delta 4bp pehX::omega Cmr, was constructed, mutated with Tn5tac1, and screened for isopropyl-beta-D-thiogalactopyranoside-dependent pectate lyase (Pel) production. A Kmr SacI fragment from the hyperexpressing Pel+ mutant CUCPB5066 was cloned into Escherichia coli and sequenced. The gene identified, pelL, encodes a novel, asparagine-rich, highly alkaline enzyme that is similar in primary structure to PelX and in enzymological properties to PelE.
构建了菊欧文氏菌突变体CUCPB5047,即Δ(pelA pelE) Δ(pelB pelC)::28bp Δ(pelX) Δ4bp pehX::ωCmr,用Tn5tac1进行诱变,并筛选对异丙基-β-D-硫代半乳糖苷依赖的果胶酸裂解酶(Pel)的产生情况。从超表达Pel+突变体CUCPB5066中克隆出一个Kmr SacI片段并导入大肠杆菌中进行测序。鉴定出的基因pelL编码一种新型的、富含天冬酰胺的高碱性酶,其一级结构与PelX相似,酶学性质与PelE相似。