Oxygenic photosynthetic organisms produce sugars through the Calvin-Benson cycle, a metabolism that is tightly linked to the light reactions of photosynthesis and is regulated by different mechanisms, including the formation of protein complexes. Two enzymes of the cycle, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), form a supramolecular complex with the regulatory protein CP12 with the formula (GAPDH-CP122-PRK)2, in which both enzyme activities are transiently inhibited during the night. Small-angle X-ray scattering analysis performed on both the GAPDH-CP12-PRK complex and its components, GAPDH-CP12 and PRK, from Arabidopsis thaliana showed that (i) PRK has an elongated, bent and screwed shape, (ii) the oxidized N-terminal region of CP12 that is not embedded in the GAPDH-CP12 complex prefers a compact conformation and (iii) the interaction of PRK with the N-terminal region of CP12 favours the approach of two GAPDH tetramers. The interaction between the GAPDH tetramers may contribute to the overall stabilization of the GAPDH-CP12-PRK complex, the structure of which is presented here for the first time.
Unravelling the shape and structural assembly of the photosynthetic GAPDH-CP12-PRK complex from Arabidopsis thaliana by small-angle X-ray scattering analysis / Del Giudice, Alessandra; Pavel, Nicolae Viorel; Galantini, Luciano; Falini, Giuseppe; Trost, Paolo; Fermani, Simona; Sparla, Francesca. - In: ACTA CRYSTALLOGRAPHICA. SECTION D. - ISSN 1399-0047. - STAMPA. - 71:Pt 12(2015), pp. 2372-2385. [10.1107/S1399004715018520]
Unravelling the shape and structural assembly of the photosynthetic GAPDH-CP12-PRK complex from Arabidopsis thaliana by small-angle X-ray scattering analysis
FALINI, GIUSEPPE;TROST, PAOLO BERNARDO;FERMANI, SIMONA;SPARLA, FRANCESCA
2015
Abstract
Oxygenic photosynthetic organisms produce sugars through the Calvin-Benson cycle, a metabolism that is tightly linked to the light reactions of photosynthesis and is regulated by different mechanisms, including the formation of protein complexes. Two enzymes of the cycle, glyceraldehyde-3-phosphate dehydrogenase (GAPDH) and phosphoribulokinase (PRK), form a supramolecular complex with the regulatory protein CP12 with the formula (GAPDH-CP122-PRK)2, in which both enzyme activities are transiently inhibited during the night. Small-angle X-ray scattering analysis performed on both the GAPDH-CP12-PRK complex and its components, GAPDH-CP12 and PRK, from Arabidopsis thaliana showed that (i) PRK has an elongated, bent and screwed shape, (ii) the oxidized N-terminal region of CP12 that is not embedded in the GAPDH-CP12 complex prefers a compact conformation and (iii) the interaction of PRK with the N-terminal region of CP12 favours the approach of two GAPDH tetramers. The interaction between the GAPDH tetramers may contribute to the overall stabilization of the GAPDH-CP12-PRK complex, the structure of which is presented here for the first time.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.