Structure, mechanism and function in the ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) superfamily
Zusammenfassung der Projektergebnisse
RuBisCO is the most abundant enzyme on earth that catalyzes the fixation of more than 95% of all atmospheric CO2 via carboxylation of D-ribulose 1,5 bisphosphate. RuBisCO-like proteins (RLPs) are homologues of RuBisCO but do not catalyze the RuBisCO reaction because they lack essential functional groups for carboxylation of D-ribulose-1,5-bisphosphate. Therefore, the challenge is to identify reactions catalyzed by these RLPs and to establish their evolutionary relationship to true RuBisCOs. In this research project, proteomics, transcriptomics and in extracto-NMR were combined with a newly developed (knock-out) metabolomics platform to determine the physiological role of the Rhodospirillum rubrum RLP. This study unravelled an unexpected link in bacterial central carbon metabolism between S-adenosylmethionine (SAM)-dependent polyamine metabolism and isoprenoid biosynthesis, indicating an interesting evolutionary link between CO2-fixing RubisCO and sulfur metabolism. Finally, the methodology used in this research project provides a novel approach for the functional assignment of unknown proteins on organismic level, which is a challenge in the era of large-scale genome sequencing.
