Complete Genome Structure of the Thermophilic Cyanobacterium Thermosynechococcus elongatus BP-1

Abstract

The entire genome of a thermophilic unicellular cyanobacterium, Thermosynechococcus elongatus BP-1, was sequenced. The genome consisted of a circular chromosome 2,593,857 bp long, and no plasmid was detected. A total of 2475 potential protein-encoding genes, one set of rRNA genes, 42 tRNA genes representing 42 tRNA species and 4 genes for small structural RNAs were assigned to the chromosome by similarity search and computer prediction. The translated products of 56% of the potential protein-encoding genes showed sequence similarity to experimentally identified and predicted proteins of known function, and the products of 34% of these genes showed sequence similarity to the translated products of hypothetical genes. The remaining 10% lacked significant similarity to genes for predicted proteins in the public DNA databases. Sixty-three percent of the T. elongatus genes showed significant sequence similarity to those of both Synechocystis sp. PCC 6803 and Anabaena sp. PCC 7120, while 22% of the genes were unique to this species, indicating a high degree of divergence of the gene information among cyanobacterial strains. The lack of genes for typical fatty acid desaturases and the presence of more genes for heat-shock proteins in comparison with other mesophilic cyanobacteria may be genomic features of thermophilic strains. A remarkable feature of the genome is the presence of 28 copies of group II introns, 8 of which contained a presumptive gene for maturase/reverse transcriptase. A trace of genome rearrangement mediated by the group II introns was also observed.

Structural insights into DndE from Escherichia coli B7A involved in DNA phosphorothioation modification

“…In addition, we measured the interaction of DndE B7A-N110 with PAPS, ATP or ADP using the isothermal titration calorimetry assay (Supplementary information, Figure S3). In contrast with the early prediction [10][11]13], DndE B7A-N110 showed no binding affinities to any of them (Supplementary information, Figure S3), consistent with the fact that the DndE B7A-N110 structure includes neither a 5′-PSB motif nor a 3′-PB motif for PAPS and PAP binding [14], nor a glycine-rich P loop for ATP or ADP phosphate binding as seen in the NCAIR synthetase [15,16]. Taken together, the crystal structure of DndE B7A-N110 reveals that DndE is neither a sulfotransferase nor a NCAIR synthase analogue, but a possible nicked ds-DNA binding protein with a previously unrecognized fold.…”

“…DndD, known as SpfD in Pseudomonas fluorescens Pf0-1, has ATPase activity possibly related to DNA structure alteration or nicking during PT incorporation [5,12]. Sequence identity (46%) and similarity (61%) to phosphoribosylaminoimidazole carboxylase (NCAIR synthetase) from Anabaena variabilis [11] suggest that DndE could be a NCAIR synthase analogue [13]. However, DndE may also act as a sulfotransferase due to a specific PAPS binding sequence AAVGK-TLLIHLHR contained in the C-terminus of DndE from Streptomyces lividans (DndE strep ) [10].…”

The Histidine Kinase Hik34 Is Involved in Thermotolerance by Regulating the Expression of Heat Shock Genes in Synechocystis

“…PCC 7120 (Kaneko et al, 2001), Thermosynechococcus elongatus BP-1 (Nakamura et al, 2002), Synechococcus sp. WH8102 (Palenik et al, 2003), Prochlorococcus marinus MIT9313 (Rocap et al, 2003), P. marinus MED4 (Rocap et al, 2003), and P. marinus SS120 (Dufresne et al, 2003), as described by Mary and Vaulot (2003).…”

slr1923 of Synechocystis sp. PCC6803 Is Essential for Conversion of 3,8-Divinyl(proto)chlorophyll(ide) to 3-Monovinyl(proto)chlorophyll(ide)

“…PCC6803 (Synechocystis 6803; Kaneko et al, 1996), Anabaena sp. PCC7120 (Kaneko et al, 2001), Thermosynechococcus elongatus BP-1 (Nakamura et al, 2002), and Gloeobacter violaceus PCC7421 (Nakamura et al, 2003), or the unicellular red alga Cyanidiochyzan merolae 10D (Matsuzaki et al, 2004). Based on the fact that these organisms synthesize MV-chl(ide), it is reasonable to assume that there exists an 8-vinyl reductase gene(s) whose amino acid sequence is rather different from those found in higher plants or C. tepidum.…”