title: Structural analysis of four large plasmids harboring in a unicellular cyanobacterium, Synechocystis sp. PCC 6803.
abstract: The genome of the unicellular cyanobacterium Synechocystis sp. PCC 6803 consists of a single chromosome and several plasmids of different sizes, and the nucleotide sequences of the chromosome and three small plasmids (5.2 kb, 2.4 kb, and 2.3 kb) have already been sequenced. We newly determined the nucleotide sequences of four large plasmids, which have been identified in our laboratory (pSYSM:120 kb, pSYSX:106 kb, pSYSA:103 kb, and pSYSG:44 kb). Computer-aided analysis was performed to explore the genetic information carried by these plasmids. A total of 397 potential protein-encoding genes were predicted, but little information was obtained about the functional relationship of plasmids to host cell, as a large portion of the predicted genes (77%) were of unknown function. The occurrence of the potential genes on plasmids was divergent, and parA was the only gene common to all four large plasmids. The distribution data of a Cyanobacterium-specific sequence (HIP1: 5'-GCGATCGC-3') suggested that respective plasmids could have originated from different cyanobacterial strains.
authors.affiliation: Kazusa DNA Research Institute, 2-6-7 Kazusa-kamatari, Kisarazu, Chiba 292-0818, Japan.
authors.forename: Takakazu
authors.initials: T
authors.lastname: Kaneko
authors.forename: Yasukazu
authors.initials: Y
authors.lastname: Nakamura
authors.forename: Shigemi
authors.initials: S
authors.lastname: Sasamoto
authors.forename: Akiko
authors.initials: A
authors.lastname: Watanabe
authors.forename: Mitsuyo
authors.initials: M
authors.lastname: Kohara
authors.forename: Midori
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Sayaka
authors.initials: S
authors.lastname: Shimpo
authors.forename: Manabu
authors.initials: M
authors.lastname: Yamada
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
mesh_terms: D001483:Base Sequence; D000458:Cyanobacteria / Q000235:genetics*; D008969:Molecular Sequence Data; D010957:Plasmids