Bates E E, Gilbert H J
Department of Agricultural Biochemistry and Nutrition, University of Newcastle upon Tyne, U.K.
Gene. 1989 Dec 21;85(1):253-8. doi: 10.1016/0378-1119(89)90491-5.
The complete nucleotide sequence of pLB4, a cryptic plasmid isolated from Lactobacillus plantarum NCDO1088 has been determined. Three open reading frames, which encode proteins of 42, 25 and 6 kDa, have been identified. In vitro transcription/translation of pLB4-derived DNA restriction fragments confirm the existence of all three polypeptides, which show homology to replication proteins and site-specific recombinases from other Gram+ plasmids. Three major regions of dyad symmetry with delta G of -28.8, -15.0 and -17.0 kcal were observed. One of these regions contains a sequence which shows perfect homology to the nick site of the Gram+ replicons, pE194, pLS1 and pADB201. In addition, a 21-bp sequence located upstream from the site-specific recombinase shows 80% homology to the recombination sites of pE194 and pT181.
已确定从植物乳杆菌NCDO1088中分离出的隐蔽质粒pLB4的完整核苷酸序列。已鉴定出三个开放阅读框，它们编码42 kDa、25 kDa和6 kDa的蛋白质。对源自pLB4的DNA限制性片段进行体外转录/翻译，证实了所有三种多肽的存在，这些多肽与其他革兰氏阳性质粒的复制蛋白和位点特异性重组酶具有同源性。观察到三个具有-28.8、-15.0和-17.0千卡ΔG的二元对称主要区域。其中一个区域包含一个与革兰氏阳性复制子pE194、pLS1和pADB201的切口位点具有完全同源性的序列。此外，位于位点特异性重组酶上游的一个21 bp序列与pE194和pT181的重组位点具有80%的同源性。
