title: Characterization of two novel plasmids from Geobacillus sp. 610 and 1121 strains.
abstract: We describe two cryptic low molecular weight plasmids, pGTD7 (3279bp) and pGTG5 (1540bp), isolated from Geobacillus sp. 610 and 1121 strains, respectively. Homology analysis of the replication protein (Rep) sequences and detection of ssDNA indicate that both of them replicate via rolling circle mechanism. As revealed by sequence similarities of dso region and Rep protein, plasmid pGTD7 belongs to pC194/pUB110 plasmid family. The replicon of pGTD7 was proved to be functional in another Geobacillus host. For this purpose, a construct pUCK7, containing a replicon of the analyzed plasmid, was created and transferred to G. stearothermophilus NUB3621R strain by electroporation. Plasmid pGTG5, based on Rep protein sequence similarity, was found to be related mostly to some poorly characterized bacterial plasmids. Rep proteins encoded by these plasmids contain conservative motifs that are most similar to those of Microviridae phages. This feature suggests that pGTG5, together with other plasmids containing the same motifs, could constitute a new family of bacterial plasmids. To date, pGTG5 is the smallest plasmid identified in bacteria belonging to the genus Geobacillus. The two plasmids described in this study can be used for the construction of new vectors suitable for biotechnologically important bacteria of the genus Geobacillus.
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Natural Sciences, Vilnius University, M. K. Ciurlionio 21/27, Vilnius LT-03101, Lithuania. Electronic address: ruta.kananaviciute@gf.vu.lt.
authors.forename: Rūta
authors.initials: R
authors.lastname: Kananavičiūtė
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Natural Sciences, Vilnius University, M. K. Ciurlionio 21/27, Vilnius LT-03101, Lithuania.
authors.forename: Elena
authors.initials: E
authors.lastname: Butaitė
authors.affiliation: Department of Microbiology and Biotechnology, Faculty of Natural Sciences, Vilnius University, M. K. Ciurlionio 21/27, Vilnius LT-03101, Lithuania.
authors.forename: Donaldas
authors.initials: D
authors.lastname: Citavičius
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics*; D056915:DNA Copy Number Variations; D004261:DNA Replication; D004269:DNA, Bacterial / Q000235:genetics / Q000302:isolation & purification*; D004277:DNA, Single-Stranded / Q000235:genetics / Q000302:isolation & purification*; D056506:Geobacillus / Q000145:classification / Q000235:genetics*; D009690:Nucleic Acid Conformation; D010957:Plasmids / Q000235:genetics*; D012336:RNA, Ribosomal, 16S / Q000235:genetics / Q000302:isolation & purification; D012093:Replicon / Q000235:genetics; D017422:Sequence Analysis, DNA
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004277:DNA, Single-Stranded; D012336:RNA, Ribosomal, 16S
keywords: Cryptic plasmid; Geobacillus sp.; Rolling circle replication