Recombinant plant gamma carbonic anhydrase homotrimers bind inorganic carbon.
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.
Martin
Victoria
V
Instituto de Investigaciones Biológicas (IIB-CONICET-UNMdP), CC 1245, 7600 Mar del Plata, Argentina.
Villarreal
Fernando
F
Miras
Isabelle
I
Navaza
Alda
A
Haouz
Ahmed
A
González-Lebrero
Rodolfo M
RM
Kaufman
Sergio B
SB
Zabaleta
Eduardo
E
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
D001639:Bicarbonates; D002250:Carbon Radioisotopes; D021122:Protein Subunits; D011994:Recombinant Proteins; D014867:Water; D002255:Carbonic Acid; D002244:Carbon; D024402:Carbonic Anhydrase II