(S)-hydroxynitrile lyase

Class of enzymes (S)-hydroxynitrile lyase 4.1.2.47 (S)-hydroxynitrile lyase (4.1.2.47, (S)-cyanohydrin producing hydroxynitrile lyase, (S)-oxynitrilase, (S)-HbHNL, (S)-MeHNL, hydroxynitrile lyase, oxynitrilase, HbHNL, MeHNL, (S)-selective hydroxynitrile lyase, (S)-cyanohydrin carbonyl-lyase (cyanide forming), hydroxynitrilase) is an enzyme with systematic name (S)-cyanohydrin lyase (cyanide forming). The first recombinant hydroxynitrile lyase and its application in the synthesis of (S)-cyanohydrins Förster, S. Roos, J. Effenberger, F. Wajant, H. Sprauer, A. Angew. Chem. Int. Ed. 1996 35 4 437–439 10.1002/anie.199604371 Substrate specificity of mutants of the hydroxynitrile lyase from Manihot esculenta Bühler, H. Effenberger, F. Förster, S. Roos, J. Wajant, H. ChemBioChem 2003 4 211–216 12616635 10.1002/cbic.200390033 2–3 Expression of hydroxynitrile lyase from Manihot esculenta in yeast and its application in (S)-mandelonitrile production using an immobilized enzyme reactor Semba, H. Dobashi, Y. Matsui, T. Biosci. Biotechnol. Biochem. 2008 72 1457–1463 18540112 10.1271/bbb.70765 6 free Improvement of a stereoselective biocatalytic synthesis by substrate and enzyme engineering: 2-hydroxy-(4-oxocyclohexyl)acetonitrile as the model Avi, M. Wiedner, R.M. Griengl, H. Schwab, H. Chemistry: A European Journal 2008 14 11415–11422 19006143 10.1002/chem.200800609 36 Hydroxynitrile lyase catalyzed cyanohydrin synthesis at high pH-values von Langermann, J. Guterl, J.K. Pohl, M. Wajant, H. Kragl, U. Bioprocess Biosyst. Eng. 2008 31 155–161 18204865 10.1007/s00449-008-0198-4 3 Atomic resolution crystal structures and quantum chemistry meet to reveal subtleties of hydroxynitrile lyase catalysis Schmidt, A. Gruber, K. Kratky, C. Lamzin, V.S. J. Biol. Chem. 2008 283 21827–21836 18524775 10.1074/jbc.m801056200 31 free Structural determinants of the enantioselectivity of the hydroxynitrile lyase from Hevea brasiliensis Gartler, G. Kratky, C. Gruber, K. J. Biotechnol. 2007 129 87–97 17250917 10.1016/j.jbiotec.2006.12.009 1 Crystallization and preliminary X-ray diffraction studies of a hydroxynitrile lyase from Hevea brasiliensis Wagner, U.G. Schall, M. Hasslacher, M. Hayn, M. Griengl, H. Schwab, H. Kratky, C. Acta Crystallogr. D 1996 52 591–593 15299689 10.1107/s0907444995016830 Pt 3 1996AcCrD..52..591W Preparation of optically active cyanohydrins using the (S)-hydroxynitrile lyase from Hevea brasiliensis Schmidt, M. Herve, S. Klempier, N. Griengl, H. Tetrahedron 1996 52 23 7833–7840 10.1016/0040-4020(96)00354-7 Aliphatic (S)-cyanohydrins by enzyme catalyzed synthesis Klempier, N. Griengl, H. Tetrahedron Lett. 1993 34 30 4769–4772 10.1016/s0040-4039(00)74084-6 This enzyme catalyses the interconversion between cyanohydrins and the carbonyl compounds derived from the cyanohydrin with free cyanide, as in the following two chemical reactions: an aliphatic (S)-hydroxynitrile an aliphatic aldehyde or ketone + cyanide an aromatic (S)-hydroxynitrile an aromatic aldehyde + cyanide In nature, the liberation of cyanide serves as a defense mechanism against herbivores and microbial attack in plants. Cyanogenesis in Plants Poultan, J.E. Plant Physiol. 1990 94 2 401–405 16667728 1077245 10.1104/pp.94.2.401 Hydroxynitrile lyases of the α/β hydrolase fold are closely related to esterases. All members of the α/β hydrolase fold contain a conserved catalytic triad (nucleophile-histidine-aspartate).Ollis, D. L. Cheah, E. Cygler, M. Dijkstra, B. Frolow, F. Franken, S. M. Harel, M. Remington, S. J. Silman, I. Schrag, J. Sussman, J. L. Verschueren, K. H. G. Goldman, A. amp The α/β hydrolase fold Protein Eng. 5 3 197–211 1992 1409539 10.1093/protein/5.3.197 https://pure.rug.nl/ws/files/3321987/1992ProteinEngOllis.pdf 11370/2d4c057d-1a67-437d-ad10-701f7a60f1e6 free The nucleophile in this case is a serine. In contrast to esterases, serine proteases, lipases and other enzymes in this family, the nucleophile in hydroxynitrile lyases functions as a proton acceptor. Cui FC Pan XL Liu JY Catalytic mechanism of hydroxynitrile lyase from Hevea brasiliensis: a theoretical investigation. J Phys Chem B 114 29 9622–8 2010 20593768 10.1021/jp100373e Key amino acid residues in this reaction are the lysine at position 236 and the threonine at position 11.Gruber K, Gartler G, Krammer B, Schwab H, Kratky C Reaction mechanism of hydroxynitrile lyases of the α/β-hydrolase superfamily: the three-dimensional structure of the transient enzyme-substrate complex certifies the crucial role of LYS236. J Biol Chem 279 19 20501–10 2004 14998991 10.1074/jbc.M401575200 free Lys236 helps to orient the substrate while Thr11 serves to block the oxyanion hole that would convert the enzyme into an esterase. Padhi SK Fujii R Legatt GA Fossum SL Berchtold R Kazlauskas RJ Switching from an esterase to a hydroxynitrile lyase mechanism requires only two amino acid substitutions. Chem. Biol. 17 8 863–71 2010 20797615 10.1016/j.chembiol.2010.06.013 Commonly studied (S)-selective hydroxynitrile lyases include MeHNL from Manihot esculenta and HbHNL from Hevea brasiliensis. (R)-selective hydroxynitrile lyases have also been found to exist in Arabidopsis thaliana (AtHNL). AtHNL is thought to catalyze this reaction by a different mechanism. The active site of hydroxynitrile lyase from Prunus amygdalus: modeling studies provide new insights into the mechanism of cyanogenesis. Andexer JN, Staunig N, Eggert T, Kratky C, Pohl M, Gruber K Protein Sci. 2002 11 2 292–300 11790839 2373431 10.1110/PS.38102 Not all hydroxynitrile lyases belong to the α/β hydrolase family. PaHNL (Prunus amygdalus), (R)-selective like AtHNL, uses a flavin cofactor to catalyze cyanogenesis. Hydroxynitrile lyases with α/β-hydrolase fold: two enzymes with almost identical 3D structures but opposite enantioselectivities and different reaction mechanisms. Dreveny I, Kratky C, Gruber K ChemBioChem 2012 13 13 1932–9 22851196 10.1002/cbic.201200239 3444685 Natural Substrates of Hydroxynitrile Lyases Acetone cyanohydrin has been determined to be the natural substrate of HbHNL, though HbHNL also shows activity with mandelonitrile, the natural substrate of PaHNL. The cleavage of mandelonitrile into benzaldehyde and cyanide is what produces the characteristic amaretto smell of almonds. Prunasin hydrolases during fruit development in sweet and bitter almonds. Sánchez-Perez, R. Saez, F. Borch, J. Dicenta, F. Moller, B. Jorgensen, K. amp Plant Physiol. 2012 158 4 1916–1932 22353576 10.1104/pp.111.192021 3320195 The natural substrate of AtHNL is unknown as no cyanohydrins have been detected in Arabidopis thaliana. Unnatural Substrates In addition to cyanohydrin cleavage, HNLs have been found to catalyze the nitroaldol reaction at low levels. Purkarthofer, T. Gruber, K. Gruber-Khadjawi, M. Waich, K. Skranc, W. Mink, D. Griengl, H. A Biocatalytic Henry Reaction—The Hydroxynitrile Lyase from Hevea brasiliensis Also Catalyzes Nitroaldol Reactions Angewandte Chemie 45 21 3454–3456 2006 16634109 10.1002/anie.200504230 2006ACIE...45.3454P References External links (S)-hydroxynitrile+lyase Biology no Category:EC 4.1.2