Crystal structure and molecular mechanism of an E/F type bilin lyase-isomerase.

ABSTRACT: Chromophore attachment of the light-harvesting apparatus represents one of the most important post-translational modifications in photosynthetic cyanobacteria. Extensive pigment diversity of cyanobacteria critically depends on bilin lyases that covalently attach chemically distinct chromophores to phycobiliproteins. However, how bilin lyases catalyze bilin ligation reactions and how some lyases acquire additional isomerase abilities remain elusive at the molecular level. Here, we report the crystal structure of a representative bilin lyase-isomerase MpeQ. This structure has revealed a "question-mark" protein architecture that unambiguously establishes the active site conserved among the E/F-type bilin lyases. Based on structural, mutational, and modeling data, we demonstrate that stereosel

SUBMITTER: Kumarapperuma I 

PROVIDER: S-EPMC8995348 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature