Stauffer L T, Plamann M D, Stauffer G V
Gene. 1986;44(2-3):219-26. doi: 10.1016/0378-1119(86)90185-x.
The glycine-cleavage enzyme system of Escherichia coli has been cloned in the cosmid vector pMF7. The recombinant plasmid, designated pGS64, carries two 19.4-kb EcoRI insert fragments. One of these fragments, which carries the gcv system, was subcloned from plasmid pGS64 into the plasmid vectors pACYC184 and pSC101 (creating plasmids pGS96 and pGS97, respectively). Plasmid pGS97, but not pGS96, complements a gcv mutant on glycine-supplemented plates. Enzyme assays, however, verified that both plasmids carry an inducible gcv system. The location of the gcv system in plasmid pGS97 was determined by Tn5 insertional inactivation. Subcloning experiments identified the region on the 19.4-kb fragment that inhibits growth in strains transformed with plasmid pGS96 and a region that is possibly involved in negative regulation of the gcv system.
大肠杆菌的甘氨酸裂解酶系统已被克隆到黏粒载体pMF7中。重组质粒命名为pGS64，携带两个19.4 kb的EcoRI插入片段。其中一个片段携带gcv系统，从质粒pGS64亚克隆到质粒载体pACYC184和pSC101中（分别产生质粒pGS96和pGS97）。在补充甘氨酸的平板上，质粒pGS97能互补gcv突变体，而pGS96不能。然而，酶活性测定证实这两种质粒都携带可诱导的gcv系统。通过Tn5插入失活确定了质粒pGS97中gcv系统的位置。亚克隆实验确定了19.4 kb片段上抑制用质粒pGS96转化的菌株生长的区域以及可能参与gcv系统负调控的区域。
