EUKARYOTIC gamma CARBONIC ANHYDRASE HOMOTRIMERS BIND INORGANIC CARBON

MARTIN, M. V.; VILLARREAL, F.; MIRAS, I.; NAVAZA, A.; ZABALETA, E

San Miguel de Tucumán

Congreso; XLV Reunión Anual SAIB; 2009

Gamma Carbonic Anhydrases (CAs) are widespread inProkaryotes. In Eukaryotes,homologous genes were found only in plant genomes coding forsubunits of the mitochondrial Complex I. At present, only ãCAhomotrimers of Methanosarcina thermophila (CAM) showreversible carbon dioxide hydration activity. However,homologous CcmM from cyanobacteria, was found to be inactiveonly conserving binding to bicarbonate. In the present work, it isshown that plant ãCA2 homotrimers bind H14CO but are unable to 3catalyse the reversible hydration of CO . These results suggest that 2plant ãCAs do not act as carbonic anhydrases but with a relatedactivity possibly contributing to recycle CO in the context of 2photorespiration