Structure of hydroxynitrile lyase from Manihot esculenta in complex with substrates acetone and chloroacetone: implications for the mechanism of cyanogenesis.

نویسندگان

  • H Lauble
  • S Förster
  • B Miehlich
  • H Wajant
  • F Effenberger
چکیده

The crystal structures of hydroxynitrile lyase from Manihot esculenta (MeHNL) complexed with the native substrate acetone and substrate analogue chloroacetone have been determined and refined at 2.2 A resolution. The substrates are positioned in the active site by hydrogen-bond interactions of the carbonyl O atom with Thr11 OG, Ser80 OG and, to a lesser extent, Cys81 SG. These studies support a mechanism for cyanogenesis as well as for the stereospecific MeHNL-catalyzed formation of (S)-cyanohydrins, which closely resembles the base-catalyzed chemical reaction of HCN with carbonyl compounds.

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عنوان ژورنال:
  • Acta crystallographica. Section D, Biological crystallography

دوره 57 Pt 2  شماره 

صفحات  -

تاریخ انتشار 2001