Insights into the structure and function of the rate-limiting enzyme of chlorophyll degradation through analysis of a bacterial Mg-dechelatase homolog.

ABSTRACT: The Mg-dechelatase enzyme encoded by the Stay-Green (SGR) gene catalyzes Mg²⁺ dechelation from chlorophyll a. This reaction is the first committed step of chlorophyll degradation pathway in plants and is thus indispensable for the process of leaf senescence. There is no structural information available for this or its related enzymes. This study aims to provide insights into the structure and reaction mechanism of the enzyme through biochemical and computational analysis of an SGR homolog from the Chloroflexi Anaerolineae (AbSGR-h). Recombinant AbSGR-h with its intact sequence and those with mutations were overexpressed in Escherichia coli and their Mg-dechelatase activity were compared. Two aspartates - D34 and D62 were found to be essential f

SUBMITTER: Dey D 

PROVIDER: S-EPMC8531759 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature