HydA2 Antibodies

Target Information

HydA2 encodes an oxygen-sensitive, chloroplast-localized [FeFe]-hydrogenase that is induced under anaerobic conditions in the green alga Chlamydomonas reinhardtii. The gene product is synthesized as a nuclear-encoded precursor that is imported into the chloroplast, where it functions in cellular hydrogen metabolism. HydA2 is a ~505 amino-acid enzyme (detected as an ~49 kDa protein in anaerobically induced cells) whose catalytic core contains the conserved motifs of [FeFe]-hydrogenases and houses the H-cluster active site, comprising a [4Fe-4S] subcluster linked to a catalytically active 2Fe subcluster (with CO and CN ligands) that supports reversible proton reduction to molecular hydrogen (H2) and H2 oxidation. Comparative modeling indicates that HydA2 forms a monomeric enzyme with an H2-gas channel architecture similar to bacterial [FeFe]-hydrogenases, while differing by lacking the N-terminal accessory Fe-S centers found in some bacterial enzymes and by containing additional algal-specific sequence insertions. Functionally, genetic analyses show HydA2 can independently catalyze H2 production, contributing-alongside HydA1-to fermentative and photosynthetically driven H2 evolution during anoxia, thereby linking chloroplast redox metabolism to hydrogen turnover.

Synonyms

HYDA2