Structural basis for a filamentous morpheein model of human cystathionine beta-synthase - PubMed
5 hours ago
- #cryo-EM
- #morpheein
- #cystathionine beta-synthase
- Human cystathionine beta-synthase (CBS) is an enzyme crucial for sulfur amino acid metabolism, hydrogen sulfide production, and cellular redox balance.
- CBS functions as a filamentous morpheein, with its stability, turnover, and activity controlled by dynamic quaternary structural transitions.
- Three distinct filamentous assemblies identified via cryo-EM: ligand-free trans-dimers forming basal filaments, adenosylornithine-bound cis-dimers in stabilized filaments, and S-adenosylmethionine-bound allo-dimers in highly stable stacked filaments.
- These reversible assemblies integrate oligomerization and allosteric regulation within a morpheein framework, redefining CBS biology.
- Findings offer new insights for targeting dysregulated CBS in diseases like homocystinuria, cancer, and Down syndrome.