Novozymes

About: Novozymes is a company organization based out in Copenhagen, Denmark. It is known for research contribution in the topics: Nucleic acid & Polynucleotide. The organization has 2506 authors who have published 2828 publications receiving 89266 citations. The organization is also known as: Novo Enzymes A/S & Novozymes A/S.

Introducing endo-xylanase activity into an exo-acting arabinofuranosidase that targets side chains

Abstract: The degradation of the plant cell wall by glycoside hydrolases is central to environmentally sustainable industries. The major polysaccharides of the plant cell wall are cellulose and xylan, a highly decorated β-1,4-xylopyranose polymer. Glycoside hydrolases displaying multiple catalytic functions may simplify the enzymes required to degrade plant cell walls, increasing the industrial potential of these composite structures. Here we test the hypothesis that glycoside hydrolase family 43 (GH43) provides a suitable scaffold for introducing additional catalytic functions into enzymes that target complex structures in the plant cell wall. We report the crystal structure of Humicola insolens AXHd3 (HiAXHd3), a GH43 arabinofuranosidase that hydrolyses O3-linked arabinose of doubly substituted xylans, a feature of the polysaccharide that is recalcitrant to degradation. HiAXHd3 displays an N-terminal five-bladed β-propeller domain and a C-terminal β-sandwich domain. The interface between the domains comprises a xylan binding cleft that houses the active site pocket. Substrate specificity is conferred by a shallow arabinose binding pocket adjacent to the deep active site pocket, and through the orientation of the xylan backbone. Modification of the rim of the active site introduces endo-xylanase activity, whereas the resultant enzyme variant, Y166A, retains arabinofuranosidase activity. These data show that the active site of HiAXHd3 is tuned to hydrolyse arabinofuranosyl or xylosyl linkages, and it is the topology of the distal regions of the substrate binding surface that confers specificity. This report demonstrates that GH43 provides a platform for generating bespoke multifunctional enzymes that target industrially significant complex substrates, exemplified by the plant cell wall.

Oxyfunctionalization of Aliphatic Compounds by a Recombinant Peroxygenase From Coprinopsis cinerea

Abstract: The goal of this study is the selective oxy- functionalization of aliphatic compounds under mild and environmentally friendly conditions using a low-cost enzymatic biocatalyst. This could be possible taking advan- tage from a new peroxidase type that catalyzes monoox- ygenase reactions with H2O2 as the only cosubstrate (peroxygenase). With this purpose, recombinant peroxyge- nase, from gene mining in the sequenced genome of Coprinopsis cinerea and heterologous expression using an industrial fungal host, is tested for the first time on aliphatic substrates. The reaction on free and esterified fatty acids and alcohols, and long-chain alkanes was followed by gas chromatography, and the different reaction products were identifiedbymassspectrometry.Regioselectivehydroxylation of saturated/unsaturated fatty acids was observed at the v-1 and v-2 positions (only at the v-2 position in myristoleic acid). Alkyl esters of fatty acids and monoglycerides were also v-1 or v-2 hydroxylated, but di- and tri-glycerides were not modified. Fatty alcohols yielded hydroxy derivatives at the v-1 or v-2 positions (diols) but also fatty acids and their hydroxy derivatives. Interestingly, the peroxygenase was able to oxyfunctionalize alkanes giving, in addition to alcohols at positions 2 or 3, dihydroxylated derivatives at both sides of the molecule. The predominance of mono- or di-hydroxyl- ated derivatives seems related to the higher or lower proportion of acetone, respectively, in the reaction medium. The recombinant C. cinerea peroxygenase appears as a promising biocatalyst for alkane activation and production of aliphatic oxygenated derivatives, with better properties than the previously reported peroxygenase from Agrocybe aegerita, and advantages related to its recombinant nature for enzyme engineering and industrial production. Biotechnol. Bioeng. 2013;110: 2323-2332. 2013 Wiley Periodicals, Inc.