A biotechnological approach to increase carbon assimilation in C3-plants

增加 C3 植物碳同化的生物技术方法

• 批准号: 25780487
• 负责人: Professorin Dr. Veronica Maurino
• 金额: --
• 依托单位: Abteilung Molekulare Pflanzenphysiologie
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2006
• 资助国家: 德国
• 起止时间: 2005-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/25780487?language=en
• 关键词: biotechnological; approach; increase; carbon; assimilation

Photorespiration starts with the competitive inhibition of CO2 fixation by O2 at the active site of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and results in a loss of at least 25% of the CO2 fixed in ambient air in C3-plants. Thus, photorespiration was considered a potentially wastefull proces that was limiting plant productivity. The prime function of the C2-pathway is to salvage glycolate 2-P by conversion to glycerate 3-P, which re-enters the C3-reductive cycle. We attempt to introduce two alternative and complete glycolate catabolic cycles into chloroplasts of the model plant Arabidopsis thaliana in order to release and re-fix the CO2 directly within the chloroplast, thereby reducing the oxygenase activity of Rubisco by increasing the CO2/O2 ratio. Thus, an autoregulatory cycle would be created which results in an attenuation of the photorespiratory pathway and an expected improvement in the efficiency of CO2 assimilation and consequently, faster biomass production. Analyses of transformants harboring fully operational glycolate cycles will also generate data to complement our understanding of function and regulation of the photorespiratory pathway and its interaction with other processes.

在c3植物中，光呼吸始于O2在核酮糖1,5-二磷酸羧化酶/加氧酶（Rubisco）活性位点对CO2固定的竞争性抑制，并导致至少25%固定在环境空气中的CO2损失。因此，光呼吸被认为是限制植物生产力的潜在浪费过程。c2途径的主要功能是通过转化甘油3-P来挽救甘油2-P，甘油3-P重新进入c3还原循环。我们试图在拟南芥模式植物的叶绿体中引入两个替代的完整的乙醇酸分解代谢循环，以便在叶绿体内直接释放和重新固定CO2，从而通过增加CO2/O2比来降低Rubisco的加氧酶活性。因此，将创建一个自调节循环，导致光呼吸途径的衰减和二氧化碳同化效率的预期改善，从而加快生物质生产。对具有完全可操作的乙醇酸循环的转化体的分析也将产生数据，以补充我们对光呼吸途径的功能和调节及其与其他过程的相互作用的理解。