title: New feruloyl esterases to access phenolic acids from grass biomass.
abstract: In the Sorangium cellulosum strain So ce56 genome, two putative esterase-encoding genes (loci sce1896 and sce8927) were cloned, expressed in Escherichia coli, and the resulting enzymes (designated ScFAE1 and ScFAE2) were used to assess the possible release of ferulic acid (FA) from triticale and wheat brans, and an aqueous fraction of steam-exploded wheat straw. The two polypeptides, sharing only 30% sequence identity, exhibit a typical catalytic Ser-Asp-His triad, a characteristic of α/β-hydrolase fold proteins. Both ScFAE1 (35 kDa) and ScFAE2 (34 kDa) were purified to apparent homogeneity and comparison of their kinetic parameters indicated an apparent higher affinity of ScFAE2 than ScFAE1 towards the various feruloyl substrates. This property was reflected by the observation that ScFAE2 was capable of yielding up to 85% of FA from destarched triticale bran. In the steam-exploded wheat sample, more than 85% yield of FA or p-coumaric acid was also effected by ScFAE2 without the decomposition of valuable chemical such as furfural. The two cloned FAEs represent the first of myxobacterial origin to be characterized and they are classified as new members of the type D family of FAEs.
authors.affiliation: Biotechnology Research Institute, National Research Council Canada, 6100 Royalmount Avenue, Montreal, QC H4P 2R2, Canada.
authors.forename: Meiqun
authors.initials: M
authors.lastname: Wu
authors.forename: Kofi
authors.initials: K
authors.lastname: Abokitse
authors.forename: Stephan
authors.initials: S
authors.lastname: Grosse
authors.forename: Hannes
authors.initials: H
authors.lastname: Leisch
authors.forename: Peter C K
authors.initials: PC
authors.lastname: Lau
mesh_terms: D000468:Alkalies / Q000737:chemistry; D000595:Amino Acid Sequence; D018533:Biomass; D002265:Carboxylic Ester Hydrolases / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D017124:Conserved Sequence; D003373:Coumaric Acids / Q000378:metabolism; D004591:Electrophoresis, Polyacrylamide Gel; D057075:Enzyme Assays; D004795:Enzyme Stability; D006863:Hydrogen-Ion Concentration; D062385:Hydroxybenzoates / Q000302:isolation & purification / Q000378:metabolism*; D007700:Kinetics; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009231:Myxococcales / Q000201:enzymology*; D006109:Poaceae / Q000378:metabolism*; D016415:Sequence Alignment; D013379:Substrate Specificity; D014908:Triticum / Q000737:chemistry
chemical_list: D000468:Alkalies; D003373:Coumaric Acids; D062385:Hydroxybenzoates; C004999:ferulic acid; D002265:Carboxylic Ester Hydrolases; C070196:feruloyl esterase; C017616:phenolic acid