title: Recombinant plant gamma carbonic anhydrase homotrimers bind inorganic carbon.
abstract: Gamma carbonic anhydrases (gammaCA) are widespread in Prokaryotes. In Eukaryotes, homologous genes were found only in plant genomes. In Arabidopsis and maize, the corresponding gene products are subunits of mitochondrial Complex I. At present, only gammaCA homotrimers of Methanosarcina thermophila (CAM) show reversible carbon dioxide (CO(2)) hydration activity. In the present work, it is shown that recombinant plant gammaCA2 could form homotrimers and bind H(14)CO(3)(-). However, they are unable to catalyse the reversible hydration of CO(2). These results suggest that plant gammaCAs do not act as carbonic anhydrases but with a related activity possibly contributing to recycle CO(2) in the context of photorespiration.
authors.affiliation: Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), CC 1245, 7600 Mar del Plata, Argentina.
authors.forename: Victoria
authors.initials: V
authors.lastname: Martin
authors.forename: Fernando
authors.initials: F
authors.lastname: Villarreal
authors.forename: Isabelle
authors.initials: I
authors.lastname: Miras
authors.forename: Alda
authors.initials: A
authors.lastname: Navaza
authors.forename: Ahmed
authors.initials: A
authors.lastname: Haouz
authors.forename: Rodolfo M
authors.initials: RM
authors.lastname: González-Lebrero
authors.forename: Sergio B
authors.initials: SB
authors.lastname: Kaufman
authors.forename: Eduardo
authors.initials: E
authors.lastname: Zabaleta
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology*; D001639:Bicarbonates / Q000378:metabolism; D002244:Carbon / Q000378:metabolism*; D002250:Carbon Radioisotopes; D002255:Carbonic Acid / Q000378:metabolism; D024402:Carbonic Anhydrase II / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D011485:Protein Binding; D055503:Protein Multimerization; D020836:Protein Structure, Quaternary; D021122:Protein Subunits / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism; D012995:Solubility; D014867:Water / Q000378:metabolism
chemical_list: D001639:Bicarbonates; D002250:Carbon Radioisotopes; D021122:Protein Subunits; D011994:Recombinant Proteins; D014867:Water; D002255:Carbonic Acid; D002244:Carbon; D024402:Carbonic Anhydrase II