The Crystal Structure of Human α2-Macroglobulin Reveals a Unique Molecular Cage

Proteolysis Lab, Molecular Biology Institute of Barcelona, CSIC, Barcelona Science Park c/Baldiri Reixac, 15-21, 08028 Barcelona (Spain)
Angewandte Chemie International Edition (Impact Factor: 11.26). 04/2012; 51(14):3340-4. DOI: 10.1002/anie.201108015
Source: PubMed


I'm your Venus: The crystal structure of the human methylamine-induced form of α(2) -macroglobulin (α(2) M) shows its large central cavity can accommodate two medium-sized proteinases (see structure, front part clipped off to better show central cavity). Twelve major entrances provide access for small substrates to the cavity and the still-active trapped "prey". The structure unveils the molecular basis of the unique "venus flytrap" mechanism of α(2) M.

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