Formation of a recombinant plasmid designated pNH603 was observed when two plasmids from incompatibility group X, the multicopy plasmid pNH602 (a higher-copy-number deletion derivative of R6K) and the oligocopy plasmid R485, coexisted in a single Escherichia coli cell. According to its size and its restriction endonuclease cleavage pattern, plasmid pNH603 is a true cointegrate of pNH602 and R485. An insertion-sequence-like element coming from plasmid R485 is supposed to mediate the fusion of both replicons. The pNH603 copy number (1-2 per chromosome) indicates that the mechanism of replication of the low-copy-number plasmid is dominant in this cointegrate. No dissociation of pNH603 to parental plasmids was observed even in E. coli K-12 recA+ cells. On the other hand, deletion derivatives of four size classes originate from pNH603 in both recA+ and recA hosts. A miniplasmid designated pNH604, a representative of the most frequent 7 Mg/mol size class, was found, in a low number of copies per host chromosome.

• MeSH
• deoxyribonukleasa BamHI MeSH
• deoxyribonukleasa EcoRI MeSH
• DNA bakterií analýza   izolace a purifikace   ultrastruktura   MeSH
• elektroforéza v polyakrylamidovém gelu MeSH
• elektronová mikroskopie MeSH
• Escherichia coli genetika   MeSH
• plazmidy * MeSH
• rekombinace genetická MeSH
• replikace DNA MeSH
• restrikční enzymy MeSH
• transpozibilní elementy DNA MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• deoxyribonukleasa BamHI MeSH
• deoxyribonukleasa EcoRI MeSH
• DNA bakterií MeSH
• restrikční enzymy MeSH
• transpozibilní elementy DNA MeSH