FIG. 5.
Plasmid map of the pEXSs expression vector derivatives pEXlacS and pEXlacOP. The lacS gene and a genomic fragment, encompassing both lacS and lacTr genes, were inserted into the polycloning site of the pEXSs plasmid to produce the pEXlacS and pEXlacOP DNA constructs. SsV1ORI indicates the 1,700-bp fragment carrying the autonomous replication sequence of the S. shibatae SSV1 viral genome. AspATPr and AspATTer are the promoter and terminator sequences of the S. solfataricus aspartate aminotransferase gene, respectively. hph is the E. coli randomly mutagenized hygromycin phosphotransferase gene. The E. coli pGEM5Zf(−) plasmid moiety lies between the two lacZ gene fragments and comprises the sequences necessary for propagation (ORI) and transformant selection for ampicillin resistance (Ampr) in E. coli.