title: Functional analysis of the plasmid pM4 replicon from Lactobacillus plantarum M4: determination of the minimal replicon and functionality identification of the putative sso.
abstract: In order to determine the minimal replicon and the single strand origin (sso) of the plasmid pM4, different fragments of pM4 were amplified by polymerase chain reaction (PCR) and cloned into pBEm, a replication probe vector for Lactobacillus. The deletion analysis results showed that the minimal replicon of pM4 could be determined within a 1280bp fragment consisting of double strand origin (dso) and rep gene encoding replication protein. Based on plasmid segregation stability assay and its ability to convert single-stranded DNA (ssDNA) to double-stranded DNA (dsDNA) by Southern hybridization, an sso of replication was located at nucleotides -118-92 in the plasmid pM4, about 300bp upstream of dso. In addition, the host range assay indicated that plasmid pM4 could replicate in L. casei 05-21, L. rhamnosus AS 1.2466(T) and L. plantarum 05-19 of all the tested Lactobacillus strains. Analysis of the pM4 replicon will allow its use in constructing a food-grade vector for application in food industry.
authors: Key Laboratory of Functional Dairy of Ministry of Education of the People's Republic of China & Municipal Government of Beijing, College of Food Science & Nutritional Engineering, China Agricultural University, Beijing, China.
authors: Sheng
authors: S
authors: Yin
authors: Yanling
authors: Y
authors: Hao
authors: Zhengyuan
authors: Z
authors: Zhai
authors: Wei
authors: W
authors: Zhang
authors: Hui
authors: H
authors: Zhou
authors: Guohong
authors: G
authors: Wang
authors: Xianli
authors: X
authors: Shi
authors: Yunbo
authors: Y
authors: Luo
mesh_terms: D004261:DNA Replication; D004277:DNA, Single-Stranded / Q000235:genetics; D005516:Food Microbiology; D005822:Genetic Vectors; D048191:Lactiplantibacillus plantarum / Q000235:genetics*; D010957:Plasmids / Q000235:genetics*; D018741:Replication Origin / Q000235:genetics; D012093:Replicon / Q000235:genetics*
chemical_list: D004277:DNA, Single-Stranded