A BACILLUS-CEREUS MEMBER OF THE SNF2 FAMILY

The complete sequence of a Bacillus cereus member of the SNF2 family o f putative helicases showed conservation of all seven motifs typical o f this family. Bcsnf predicted a protein of 1064 aa where the conserve d SNF2 domain was located at the carboxy terminus, whereas the 633 ami no-terminal aa showed no homology to any protein in the databases. A p utative transcriptional start was identified by primer extension, indi cating that Bcsnf is not a part of a larger operon. No phenotypical ch anges were observed after insertional inactivation of Bcsnf. The compl etely sequenced genomes of Mycoplasma genitalium and Haemophilus influ enzae contain one ORF each with similarity to the SNF2 family: MG018 a nd HI0616, respectively. A phylogenetic tree of the SNF2 family showed that BcSNF and MG018 were most closely related, and appeared closer t o the eukaryotic members of the SNF2 family than to the two other bact erial members of the family. HepA from Escherichia coli and HI0616.