title: Cloning of the hsp70 (dnaK) genes from Rhizobium meliloti and Pseudomonas cepacia: phylogenetic analyses of mitochondrial origin based on a highly conserved protein sequence.
abstract: The genes for hsp70 (or dnaK) have been cloned and sequenced from Rhizobium meliloti and Pseudomonas cepacia, two bacterial species belonging to the alpha- and beta-subdivisions of gram-negative proteobacteria, respectively. On the basis of global alignment of HSP70 proteins, several sequence signatures have been identified that are distinctive of mitochondrial homologs and gram-negative proteobacteria on the one hand and the chloroplasts and cyanobacteria on the other. Detailed phylogenetic analyses of HSP70 sequences from various eubacteria and eukaryotic organellar and cytosolic homologs support the inference regarding the origin of mitochondria from a member of the alpha-proteobacteria and of chloroplasts from cyanobacteria. The analysis presented here also suggests a monophyletic origin of the mitochondrial homologs.
authors.affiliation: Department of Biochemistry, McMaster University, Hamilton, Ontario, Canada.
authors.forename: M
authors.initials: M
authors.lastname: Falah
authors.forename: R S
authors.initials: RS
authors.lastname: Gupta
mesh_terms: D000595:Amino Acid Sequence; D016956:Burkholderia cepacia / Q000145:classification / Q000235:genetics*; D002736:Chloroplasts / Q000235:genetics; D003001:Cloning, Molecular; D017124:Conserved Sequence; D000458:Cyanobacteria / Q000235:genetics; D029968:Escherichia coli Proteins; D005798:Genes, Bacterial / Q000235:genetics*; D006090:Gram-Negative Bacteria / Q000145:classification / Q000235:genetics; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D008928:Mitochondria / Q000235:genetics; D008969:Molecular Sequence Data; D010802:Phylogeny; D017386:Sequence Homology, Amino Acid; D016962:Sinorhizobium meliloti / Q000145:classification / Q000235:genetics*
chemical_list: D029968:Escherichia coli Proteins; D018840:HSP70 Heat-Shock Proteins; C063842:dnaK protein, E coli