Complete genome sequence of the alkaliphilic bacterium Bacillus haloduransand genomic sequence comparison with Bacillus subtilis

The 4 202 353 bp genome of the alkaliphilic bacterium Bacillus halodurans C -125 contains 4066 predicted protein coding sequences (CDSs), 2141 (52.7%) of which have functional assignments, 1182 (29%) of which are conserved CDS s with unknown function and 743 (18.3%) of which have no match to any prote in database. Among the total CDSs, 8.8% match sequences of proteins found o nly in Bacillus subtilis and 66.7% are widely conserved in comparison with the proteins of various organisms, including B.subtilis. The B.halodurans g enome contains 112 transposase genes, indicating that transposases have pla yed an important evolutionary role in horizontal gene transfer and also in internal genetic rearrangement in the genome. Strain C-125 lacks some of th e necessary genes for competence, such as comS, srfA and rapC, supporting t he fact that competence has not been demonstrated experimentally in C-125. There is no paralog of tupA, encoding teichurono-peptide, which contributes to alkaliphily, in the C-125 genome and an ortholog of tupA cannot be foun d in the B.subtilis genome. Out of 11 sigma factors which belong to the ext racytoplasmic function family, 10 are unique to B.halodurans, suggesting th at they may have a role in the special mechanism of adaptation to an alkali ne environment.