From Linum usitatissimum

Roberge, C., Fleitz, F., Pollard, D. and Devine, P., Synthesis of optically active cyanohydrins from aromatic ketones evidence of an increased substrate range and inverted stereoselectivity for the hydroxynitrile lyase from Linum usitatissimum. Tetrahedron Asymm., 2007,18, 208. 

Despite their lack of stabilizing disulfide bridges Potl inhibitors feature a common, stable fold. The N-terminus is coiled, although in some structures a small /3-strand has been identified. After a turn the structure adopts an a-helical structure, followed by a turn and an other /3-strand. The sequence then features an extended turn or loop motif that contains the reactive site of the inhibitor before it proceeds with a /3-strand running almost parallel to the /3-strand after the a-helix. After another turn and coiled motif a short /3-strand antiparallel to the other /3-strands precedes the coiled C-terminus. Usually the N-terminal residue in the reactive site is an acidic residue followed by an aromatic amino acid, that is, tyrosine or phenylalanine. Figure 11 shows the complex of chymotrypsin inhibitor (Cl) 2 with subtilisin, the hexamer of Cl 2 from H. vulgare and a structural comparison with a trypsin inhibitor from Linum usitatissimum ... 

Linoleic (18 2) and linolenic acids (18 3) from Linum usitatissimum, the hax plant. This is grown not only for linseed oil but for hbre, to produce linen. 

HNLs comprise a heterogenous enzyme family, since hydroxynitrile lyase activity has evolved in different structural frames by convergent evolution [17, 18]. Thus, (S) -specific HNLs based on an a/P-hydrolase fold framework from Manihot esculmta (cassava) [19-21], Hevea hrasilensis (rubber tree) [22-26], and Sorghum hicolor (millet) [27-33] have been described. (R)-specific HNLs based on the structural framework of oxidoreductases were isolated from Linum usitatissimum (flax) [30, 34-37] and Rosaceae (e.g., bitter almonds) [31, 38]. Despite their potential in biocatalysis only few HNLs (from cassava and rubber tree) are available by recombinant gene expression, which is a prerequisite for their technical application [20, 24]. Thus, cloning, recombinant expression, and... 

J. Albrecht, 1. Jansen, M. R. Kula, Improved purification of an (R)-oxynitrilase from Linum usitatissimum (flax) and investigation of the substrate range. Biotechnol. Appl. Biochem. 1993,... 

Cloning and expression of (R)-hydroxynitrile lyase from Linum usitatissimum (flax)./. Mol. Catal. B -Enzymaticl999, 6, 315-332. 

Cutler, A.J., Sternberg, M. and Corm, E.E. (1985) Properties of a microsomal enzyme system from Linum usitatissimum (linen flax), which oxidizes valine to acetone cyanohydrin and isoleucine to 2-methylbutanone cyanohydrin. Arch. Biochem. Biophys., 238,272-9. 

Hahlbrock, K. and Gonn, E.E. (1970) The biosynthesis of cyanogenic glycosides in higher plants purification and properties of a uridine diphosphate-glucose-ketone cyanohydrin p-glucosyltransferase from Linum usitatissimum (L.). /. Biol. Chem., 245, 917-22. 

Xu, L.L., Singh, B.K. and Conn, E.E. (1988) Purification and characterization of acetone cyanohydrin lyase from Linum usitatissimum. Arch. Biochem. Biophys., 263, 256-64. 

LINSEED (Flax), Lint semen is harvested from Linum usitatissimum L., family Linaceae. The plant has been cultivated for centuries in Europe for textile purposes. In the epidermis of the seed coat there is 3-6% mucilage consisting of galacturonic acid, galactose, rhamnose, and arabinose, mannuronic acid. Linseed is cheap and simple to use as a laxative 1 spoon of linseed is allowed to swell overnight in a cup of water, and next morning the contents of the cup are swallowed. Its value has been demonstrated in two studies of patients with constipation. 

Other (R)-oxynitrilases have also been used for the purpose of cyanohydrin formation. One of them is the oxynitrilase from Linum usitatissimum (flax). 

P)-Oxynitrilase from Linum usitatissimum has been used for the synthesis of (R)-butan-2-one cyanohydrin on a preparative scale 651. 

Flax, fibre from Linum usitatissimum (the source of linseed oil) and numerous other plants. 

As described in Sec. III.A, PaHNL from bitter almonds is an excellent biocatalyst for the preparation of (.R)-cyanohydrins. Since the functional overexpression of PaHNL was not successful so far and some substrates, e.g., acrolein, gave only low optical yields, the catalytic suitability of the (J )-specific HNL from Linum usitatissimum [30] for the preparation of (/ )-cyanohydiins was recently investigated [31]. The HNL from L. usitatissimum has been cloned and overexpressed in P. pastoris giving convenient access to recombinant enzyme for synthetic plications [31]. In Table 10 the LuHNL-catalyzed addition of HCN to alddiydes and ketones yielding the corresponding (P)-cyanohydrins is summarized [31b]. 

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