Mode and origin of replication of pSAM2, a conjugative integrating element of Streptomyces ambofaciens.
pSAM2 is an 11 kb integrating element from Streptomyces ambofaciens that is capable of replication. It generates single-stranded DNA during replication, and is therefore the first Streptomyces integrating element to be described that may belong to the family of elements, called the ssDNA elements, that replicate by a rolling-circle mechanism. The direction of replication has been identified. The plus origin (ori) of replication and minus origin (M-O) have been located. Streptomyces lividans harbouring replicating pSAM2 also contain numerous small covalently closed circular DNA molecules (scm) derived from pSAM2. These scm contain ori and extend on both sides of the putative nick site. Sequences at the junction points of these scm are heterogeneous but short direct repeats were always found in the vicinity of these junctions.
Hagège
J
J
Institut de Génétique et Microbiologie, URA CNRS 1354, Bâtiment 400, Université Paris-Sud, Orsay, France.
Pernodet
J L
JL
Friedmann
A
A
Guérineau
M
M
D000595:Amino Acid Sequence; D001483:Base Sequence; D003227:Conjugation, Genetic; D004261:DNA Replication / Q000235:genetics*; D004251:DNA Transposable Elements / Q000235:genetics*; D004269:DNA, Bacterial / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics; D004277:DNA, Single-Stranded / Q000378:metabolism; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000235:genetics; D018741:Replication Origin / Q000235:genetics*; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism
D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D004277:DNA, Single-Stranded