Open AccessExpression of the mobM gene of the streptococcal plasmid pMV158 in Lactococcus lactis subsp. lactis
Author(s) -
Farı́as Marı́a Eugenia,
Grohmann Elisabeth,
Espinosa Manuel
Publication year - 1999
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1999.tb13690.x
Subject(s) - lactococcus lactis , plasmid , biology , gene , bacteria , transcription (linguistics) , dna , microbiology and biotechnology , genetics , lactic acid , linguistics , philosophy
The streptococcal plasmid pMV158 is not auto‐transferable, but it can be mobilised between bacteria by the use of functions supplied by plasmids of the pIP501/pAMβ1 family. Plasmid pMV158 encodes a protein, MobM, which is involved in its mobilisation. This process initiates when MobM specifically cleaves supercoiled pMV158 plasmid DNA at the origin of transfer, oriT . Plasmid pMV158 has been transferred to Lactococcus lactis by conjugation aided by plasmid pAMβ1. In the lactococcal host, MobM‐mediated specific pMV158‐relaxed molecules were detected. The intracellular amount of MobM has been quantified by immunoblot analyses and shown to be about 3500 molecules per cell. In the same host, we have mapped the initiation point of transcription of mobM . Transcription of this gene is directed from a promoter with an extended −10 region which overlaps with the pMV158‐ oriT .