title: An unusual gene containing a dnaJ N-terminal box flanks the putative origin of replication of Mycoplasma genitalium.
abstract: Origins of replication are known to be highly conserved among widely divergent microbial species, with the gene order in those regions being dnaA-dnaN-recF-gyrB. On the basis of sequence identities to entries in GenBank, the gene order of a 6-kb fragment of Mycoplasma genitalium DNA was determined to be dnaN-orf311-gyrB-gyrA-serS, which is structurally similar to the ancestral origin of replication. We have directly linked the dnaN gene to the M. genitalium dnaA gene by PCR amplification. However, we found a novel open reading frame, designated orf311, in place of an expected sequence encoding recF. Orf311 contains a DnaJ box motif at its N terminus, but it has no overall homology to any other protein or sequence in the database. We are unable to detect any recF homolog in M. genitalium by hybridization or during a random sequencing survey of the genome.
authors.affiliation: Department of Microbiology and Immunology, University of North Carolina at Chapel Hill.
authors.forename: C C
authors.initials: CC
authors.lastname: Bailey
authors.forename: K F
authors.initials: KF
authors.lastname: Bott
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D002874:Chromosome Mapping; D002876:Chromosomes, Bacterial; D027081:DNA Gyrase; D004261:DNA Replication / Q000235:genetics*; D004250:DNA Topoisomerases, Type II / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D004259:DNA-Directed DNA Polymerase; D005798:Genes, Bacterial / Q000235:genetics*; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D009174:Mycoplasma / Q000235:genetics*; D016366:Open Reading Frames / Q000235:genetics; D017386:Sequence Homology, Amino Acid
chemical_list: D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; C066312:DnaA protein, Bacteria; D050956:HSP40 Heat-Shock Proteins; D006360:Heat-Shock Proteins; C066218:recF protein, Bacteria; D004259:DNA-Directed DNA Polymerase; C083980:dnaN protein, Bacteria; D027081:DNA Gyrase; D004250:DNA Topoisomerases, Type II