Mondou F, Shareck F, Morosoli R, Kluepfel D
Gene. 1986;49(3):323-9. doi: 10.1016/0378-1119(86)90368-9.
The xylanase (xln) gene of Streptomyces lividans 1326 was cloned by functional complementation of the xylanase-negative and beta-1,4-glucan-glucanohydrolase-negative double mutant of S. lividans using the multicopy plasmid pIJ702. Three clones had a common 2-kb DNA fragment as determined by restriction mapping and Southern hybridization. These clones secreted a xylanase of Mr 43,000 which reacted with specific anti-xylanase antibodies and corresponded exactly to the enzyme previously isolated from the wild-type strain. The DNA fragment likely carried the full structural gene, the xln promoter and also the regulatory sequence, since the xylanase activity was inducible by xylan. Enzyme levels of up to 380 IU/ml of culture filtrate were obtained.
使用多拷贝质粒pIJ702，通过对变铅青链霉菌木聚糖酶阴性和β-1,4-葡聚糖-葡聚糖水解酶阴性的双突变体进行功能互补，克隆了变铅青链霉菌1326的木聚糖酶（xln）基因。通过限制性图谱分析和Southern杂交确定，三个克隆具有一个共同的2kb DNA片段。这些克隆分泌一种分子量为43,000的木聚糖酶，该酶与特异性抗木聚糖酶抗体发生反应，并且与先前从野生型菌株中分离出的酶完全一致。该DNA片段可能携带完整的结构基因、xln启动子以及调控序列，因为木聚糖酶活性可被木聚糖诱导。培养滤液中的酶水平高达380 IU/ml。
