Complete sequence of plasmid pMP1 from the marine environmental Vibrio vulnificus and location of its replication origin.

摘要: A novel cryptic plasmid, pMP1, from an environmental Vibrio vulnificus MP-4 isolated Mai Po Nature Reserve in Hong Kong, has been characterized. The 7.6-kb plasmid had guanine-cytosine content of 40.03% and encoded four open reading frames (ORFs) with >100 amino acids. predicted protein ORF1 contained 478 acids showing 29% identity 50% similarity over 309 to the integrase cholerae phage VP2. ORF2 a putative 596 acids, which were 23% 42% 455 tail tape measure TP901 Chromohalobacter salexigens phage. ORF3 ORF4 proteins 103 287 respectively, but showed no homologies any known proteins. Further experiments indicated that 3.2-kb fragment EcoRI digestion could self-replicate. Analysis sequence upstream features characteristic theta-type replicons: AT-rich region, six potential direct repeats (iterons) spaced approximately two DNA helical turn apart (about 23 bp), copies 9 bp dnaA boxes, three Dam methylation sites, five inverted repeats. Complementation confirmed by was required for replication. We propose encode new type Rep pMP1 is theta plasmid.