A biotechnological approach to increase carbon assimilation in C3-plants
Zusammenfassung der Projektergebnisse
In this work a novel biotechnological approach to increase carbon assimilation and biomass in C3-plants was tested in the model plant A. thaliana. The selection and characterization of single, triple and quadruple mutants was achieved. The analysis of the GTT and GMM plants showed that the expression of the whole pathway could partially rescue the GO phenotype. Nevertheless, the plants remain smaller than the wild type. Furthermore, an improvement of the GMM pathway could not be achieved by introducing catalase into the chloroplasts (GMMK plants). In order to circumvent the deleterious effects of both, excess H2O2 produced in the chloroplasts due to the expression of GO and the altered malate/fumarate metabolism due to the overexpression of NADP-ME, the E. coli catalase gene was co-expressed in double GO-MS transformants, generating the GMK pathway. The analysis of the GMK plants demonstrated that it is possible to enhance biomass accumulation in A. thaliana by introducing a C4-like CO2 concentrating mechanism. Further analysis of the photosynthetic performance of these plants (carbon assimilation rate, compensation point) is being conducted.