title: Rhizobium meliloti adenylate cyclase: probing of a NTP-binding site common to cyclases and cation transporters.
abstract: Alignments between amino acid sequences of eukaryotic adenylate (ACase) and guanylate (GCase) cyclases and the prokaryotic Rhizobium meliloti ACase revealed four conserved regions. Two were the target of site-directed mutagenesis. A positive charge at position 44 converted the enzyme to GCase, a negative charge at this position had no effect. A second modification indicated that residues 107 and 124 contribute to the nucleoside triphosphate binding pocket's conformation. This latter region was used to scan protein sequences data banks. A similar region was detected in the family of E1-E2 type ATPases. Topographical resemblance between these ATPases, eukaryotic ACases and several transporters suggest that they evolved from a common ancestor.
authors.affiliation: CNRS URA 1129, Département de Biochimie et Génétique Moléculaire, Institut Pasteur, Paris, France.
authors.forename: A
authors.initials: A
authors.lastname: Beuve
authors.forename: E
authors.initials: E
authors.lastname: Krin
authors.forename: A
authors.initials: A
authors.lastname: Danchin
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism*; D000262:Adenylyl Cyclases / Q000378:metabolism*; D001665:Binding Sites; D001692:Biological Transport; D002412:Cations / Q000378:metabolism; D005057:Eukaryotic Cells / Q000201:enzymology; D006162:Guanylate Cyclase / Q000378:metabolism; D066298:In Vitro Techniques; D009711:Nucleotides / Q000378:metabolism*; D016415:Sequence Alignment; D016962:Sinorhizobium meliloti / Q000201:enzymology*; D013379:Substrate Specificity
chemical_list: D002412:Cations; D009711:Nucleotides; D000251:Adenosine Triphosphatases; D000262:Adenylyl Cyclases; D006162:Guanylate Cyclase