Substrate Report for: Methyl-ferulate

ESTHER: Martinez-Martinez_2018_ACS.Chem.Biol_13_225
PubMedSearch: Martinez-Martinez 2018 ACS.Chem.Biol 13 225
PubMedID: 29182315
Gene_locus related to this paper: 9zzzz-a0a2k8jn75, 9zzzz-a0a2k8jt94, 9zzzz-a0a0g3fj44, 9zzzz-a0a0g3fh10, 9zzzz-a0a0g3fh03, 9bact-a0a1s5qkj8, 9zzzz-a0a0g3feh5, 9zzzz-a0a0g3fkz4, 9zzzz-a0a0g3fh07, 9zzzz-a0a0g3fh34, 9zzzz-a0a0g3fh31, 9bact-KY458167, alcbs-q0vqa3, 9bact-a0a1s5qki8, 9zzzz-a0a0g3feq8, 9zzzz-a0a0g3feh8, 9zzzz-a0a0g3fh19, 9bact-KY203037, 9bact-a0a1s5ql22, 9bact-a0a1s5qm34, 9bact-KY203034, 9bact-r9qzg0, 9bact-a0a1s5qly8, 9zzzz-a0a0g3fkz8, 9zzzz-a0a0g3feg9, 9zzzz-KY203033, 9zzzz-a0a0g3fes4, 9zzzz-a0a0g3fh42, 9bact-a0a1s5qlx2, 9zzzz-KY483651, 9bact-a0a1s5qmh4, 9zzzz-KY203032, 9zzzz-EH87, 9zzzz-a0a0g3fei1, 9zzzz-a0a0g3fet2, 9zzzz-KY483647, 9zzzz-EH82, 9zzzz-a0a0g3fe15, 9bact-KY203031, 9bact-t1w006, 9zzzz-a0a0g3fet6, 9bact-KY458164, geoth-g8myf3, 9bact-a0a1s5ql04, 9gamm-a0a1y0ihk7, 9bact-a0a1s5qly6, 9bact-a0a1s5qkg4, 9bact-a0a1s5qkm4, 9gamm-s5tv80, 9gamm-a0a0c4zhg2, 9zzzz-t1b379, 9gamm-KY483646, 9bact-KY458160, 9zzzz-a0a0g3fj57, 9gamm-s5t8349, 9arch-KY203036, 9bact-KY458168, 9zzzz-a0a0g3fes0, 9zzzz-t1be47, 9bact-KY458159, 9zzzz-a0a0g3fh39, 9bact-t1vzd5, 9prot-EH41, 9bact-Lip114, alcbs-q0vt77, 9bact-a0a1s5qke6, 9bact-a0a1s5qkf3, 9prot-SRP030024, 9gamm-s5t532, 9bact-a0a1s5qkl2, 9bact-a0a1s5qkk8, 9zzzz-KY203030, 9zzzz-t1d4I7, 9prot-KY019260, 9bact-a0a1s5qm38, 9arch-KY458161, 9prot-KY010302, 9zzzz-a0a0g3fl25, 9actn-KY010298, 9gamm-s5u059, 9bact-a0a1s5qmi7, 9bact-KY010297, 9bact-KY483642, 9bact-a0a1s5qkj1, 9bact-KY010299, 9bact-KY483648, alcbs-q0vtl7, 9bact-a0a1s5qf1, 9bact-a0a1s5qkg0, 9bact-a0a0h4tgu6, 9bact-MilE3, 9bact-LAE6, 9alte-MGS-MT1, 9bact-r9qzf7, 9gamm-k0c6t6, alcbs-q0vl36, alcbs-q0vlq1, alcbs-q0vq49, bacsu-pnbae, canar-LipB, canan-lipasA, geost-lipas, marav-a1u5n0, pseps-i7k8x5, staep-GEHD, symth-q67mr3, altma-s5cfn7, cycsp-k0c2b8, alcbs-q0vlk5, 9bact-k7qe48, 9bact-MGS-M1, 9bact-MGS-M2, 9bact-a0a0b5kns5, 9zzzz-a0a0g3fej4, 9zzzz-a0a0g3fj60, 9zzzz-a0a0g3fej0, 9zzzz-a0a0g3fj64, 9bact-a0a0b5kc16, 9zzzz-a0a0g3feg6, 9zzzz-a0a0g3feu6

Abstract

Esterases receive special attention because their wide distribution in biological systems and environments and their importance for physiology and chemical synthesis. The prediction of esterases substrate promiscuity level from sequence data and the molecular reasons why certain such enzymes are more promiscuous than others, remain to be elucidated. This limits the surveillance of the sequence space for esterases potentially leading to new versatile biocatalysts and new insights into their role in cellular function. Here we performed an extensive analysis of the substrate spectra of 145 phylogenetically and environmentally diverse microbial esterases, when tested with 96 diverse esters. We determined the primary factors shaping their substrate range by analyzing substrate range patterns in combination with structural analysis and protein-ligand simulations. We found a structural parameter that helps ranking (classifying) promiscuity level of esterases from sequence data at 94% accuracy. This parameter, the active site effective volume, exemplifies the topology of the catalytic environment by measuring the active site cavity volume corrected by the relative solvent accessible surface area (SASA) of the catalytic triad. Sequences encoding esterases with active site effective volumes (cavity volume/SASA) above a threshold show greater substrate spectra, which can be further extended in combination with phylogenetic data. This measure provides also a valuable tool for interrogating substrates capable of being converted. This measure, found to be transferred to phosphatases of the haloalkanoic acid dehalogenase superfamily and possibly other enzymatic systems, represents a powerful tool for low-cost bioprospecting for esterases with broad substrate ranges, in large scale sequence datasets.

ESTHER: Wefers_2017_J.Mol.Biol_429_2509
PubMedSearch: Wefers 2017 J.Mol.Biol 429 2509
PubMedID: 28669823
Gene_locus related to this paper: 9bace-b3c9d0.2, 9bace-b3cet1

Abstract

Arabinoxylans are constituents of the human diet. Although not utilizable by the human host, they can be fermented by colonic bacteria. The arabinoxylan backbone is decorated with arabinose side chains that may be substituted with ferulic acid, thus limiting depolymerization to fermentable sugars. We investigated the polypeptides encoded by two genes upregulated during growth of the colonic bacterium Bacteroides intestinalis on wheat arabinoxylan. The recombinant proteins, designated BiFae1A and BiFae1B, were functionally assigned esterase activities. Both enzymes were active on acetylated substrates, although each showed a higher ferulic acid esterase activity on methyl-ferulate. BiFae1A showed a catalytic efficiency of 12mM s(-1) on para-nitrophenyl-acetate, and on methyl-ferulate, the value was 27 times higher. BiFae1B showed low catalytic efficiencies for both substrates. Furthermore, the two enzymes released ferulic acid from various structural elements, and NMR spectroscopy indicated complete de-esterification of arabinoxylan oligosaccharides from wheat bran. BiFae1A is a tetramer based on the crystal structure, whereas BiFae1B is a dimer in solution based on size exclusion chromatography. The structure of BiFae1A was solved to 1.98A resolution, and two tetramers were observed in the asymmetric unit. A flexible loop that may act as a hinge over the active site and likely coordinates critical interactions with the substrate was prominent in BiFae1A. Sequence alignments of the esterase domains in BiFae1B with the feruloyl esterase from Clostridium thermocellum suggest that both domains lack the flexible hinge in BiFae1A, an observation that may partly provide a molecular basis for the differences in activities in the two esterases.

ESTHER: Bauer_2006_Proc.Natl.Acad.Sci.U.S.A_103_11417
PubMedSearch: Bauer 2006 Proc.Natl.Acad.Sci.U.S.A 103 11417
PubMedID: 16844780
Gene_locus related to this paper: emeni-axe1, emeni-CUTI3, emeni-faec

Abstract

To facilitate analysis of plant cell wall polysaccharide structure and composition, we cloned 74 genes encoding polysaccharide-degrading enzymes from Aspergillus nidulans, Aspergillus fumigatus, and Neurospora crassa and expressed the genes as secreted proteins with C-terminal Myc and 6x His tags. Most of the recombinant enzymes were active in enzyme assays, and optima for pH and temperature were established. A subset of the enzymes was used to fragment polysaccharides from the irregular xylem 9 (irx9) mutant of Arabidopsis. The analysis revealed a decrease in the abundance of xylan in the mutant, indicating that the IRX9 gene, which encodes a putative family 43 glycosyltransferase, is required for xylan synthesis.

ESTHER: Lin_2023_Int.J.Biol.Macromol__123365
PubMedSearch: Lin 2023 Int.J.Biol.Macromol 123365
PubMedID: 36690236
Gene_locus related to this paper: humin-HiFae1, malci-McFae1, 9zzzz-CE1.6RZN, 9zzzz-DAC80243, 9pezi-a0a481sy08, aspni-FAEA, aspor-q2uh24, aspor-q2umx6, aspor-q2unw5, aspor-q2up89, neucr-faeb, magoy-l7ic25

Abstract

Feruloyl esterases (FAEs, EC 3.1.1.73) catalyze the hydrolytic cleavage of ester bonds between feruloyl and arabinosyl moieties in arabinoxylans. Recently, we discovered that two bacterial FAEs could catalyze release of diferulic acid moieties (diFAs) from highly substituted, cross-linked corn bran arabinoxylan. Here, we show that several fungal FAEs, notably AnFae1 (Aspergillus niger), AoFae1 (A. oryzae), and MgFae1 (Magnaporthe oryzae (also known as M. grisae)) also catalyze liberation of diFAs from complex arabinoxylan. By comparing the enzyme kinetics of diFA release to feruloyl esterase activity of the enzymes on methyl- and arabinosyl-ferulate substrates we demonstrate that the diFA release activity cannot be predicted from the activity of the enzymes on these synthetic substrates. A detailed structure-function analysis, based on AlphaFold2 modeled enzyme structures and docking with the relevant di-feruloyl ligands, reveal how distinct differences in the active site topology and surroundings may explain the diFA releasing action of the enzymes. Interestingly, the analysis also unveils that the carbohydrate binding module of the MgFae1 may play a key role in the diFA releasing ability of this enzyme. The findings contribute further understanding of the function of FAEs in the deconstruction of complex arabinoxylans and provide new opportunities for enzyme assisted upgrading of complex bran arabinoxylans.

ESTHER: Kasmaei_2022_Front.Microbiol_13_1050160
PubMedSearch: Kasmaei 2022 Front.Microbiol 13 1050160
PubMedID: 36569051
Gene_locus related to this paper: lenbu-d7ru28

Abstract

Ferulic acid is a common constituent of the plant cell-wall matrix where it decorates and can crosslink mainly arabinoxylans to provide structural reinforcement. Microbial feruloyl esterases (FAEs) specialize in catalyzing hydrolysis of the ester bonds between phenolic acids and sugar residues in plant cell-wall polysaccharides such as arabinoxylan to release cinnamoyl compounds. Feruloyl esterases from lactic acid bacteria (LAB) have been highlighted as interesting enzymes for their potential applications in the food and pharmaceutical industries; however, there are few studies on the activity and structure of FAEs of LAB origin. Here, we report the crystal structure and biochemical characterization of a feruloyl esterase (LbFAE) from Lentilactobacillus buchneri, a LAB strain that has been used as a silage additive. The LbFAE structure was determined in the absence and presence of product (FA) and reveals a new type of homodimer association not previously observed for fungal or bacterial FAEs. The two subunits associate to restrict access to the active site such that only single FA chains attached to arabinoxylan can be accommodated, an arrangement that excludes access to FA cross-links between arabinoxylan chains. This narrow specificity is further corroborated by the observation that no FA dimers are produced, only FA, when feruloylated arabinoxylan is used as substrate. Docking of arabinofuranosyl-ferulate in the LbFAE structure highlights the restricted active site and lends further support to our hypothesis that LbFAE is specific for single FA side chains in arabinoxylan.

ESTHER: Phuengmaung_2019_Enzyme.Microb.Technol_131_109380
PubMedSearch: Phuengmaung 2019 Enzyme.Microb.Technol 131 109380
PubMedID: 31615673
Gene_locus related to this paper: pench-q3v6c9

Abstract

We previously described the fungus Penicillium chrysogenum 31B, which has high performance to produce the ferulic acid esterase (FAE) for de-esterifying ferulic acids (FAs) from sugar beet pulp. However, the characteristics of this fungus have not yet been determined. Therefore, in this study, we evaluated the molecular characteristics and natural substrate specificity of the Pcfae1 gene from Penicillium chrysogenum and examined its synergistic effects on sugar beet pectin. The Pcfae1 gene was cloned and overexpressed in Pichia pastoris KM71H, and the recombinant enzyme, named PcFAE1, was characterized. The 505 amino acids of PcFAE1 possessed a GCSTG motif (Gly164 to Gly168), characteristic of the serine esterase family. By comparing the amino acid sequence of PcFAE1 with that of the FAE (AoFaeB) of Aspergillus oryzae, Ser166, Asp379, and His419 were identified as the catalytic triad. PcFAE1 was purified through two steps using anion-exchange column chromatography. Its molecular mass without the signal peptide was 75 kDa. Maximum PcFAE1 activity was achieved at pH 6.0-7.0 and 50 degreesC. The enzyme was stable up to 37 degreesC and at a pH range of 3-8. PcFAE1 activity was only inhibited by Hg(2+), and the enzyme had activity toward methyl FA, methyl caffeic acid, and methyl p-coumaric acid, with specific activities of 6.97, 4.65, and 9.32 U/mg, respectively, but not on methyl sinapinic acid. These results indicated that PcFAE1 acted similar to FaeB type according the Crepin classification. PcFAE1 de-esterified O-[6-O-feruloyl-beta-d-galactopyranosyl-(14)]-d-galactopyranose, O-[2-O-feruloyl-alpha-l-arabinofuranosyl-(15)]-l-arabinofuranose, and O-[5-O-feruloyl-alpha-l-arabinofuranosyl-(13)]-O-beta-d-xylopyranosyl-(14)-d-xylopyranose, indicating that the enzyme could de-esterify FAs decorated with both beta-d-galactopyranosidic and alpha-l-arabinofuranosidic residues in pectin and xylan. PcFAE1 acted in synergy with endo-alpha-1,5-arabinanase and alpha-l-arabinofuranosidase, which releases FA linked to arabinan, to digest the sugar beet pectin. Moreover, when PcFAE1 was allowed to act on sugar beet pectin together with Driselase, approximately 90% of total FA in the substrate was released. Therefore, PcFAE1 may be an interesting candidate for hydrolysis of lignocellulosic materials and could have applications as a tool for production of FA from natural substrates.

ESTHER: Makela_2018_Microb.Biotechnol_11_869
PubMedSearch: Makela 2018 Microb.Biotechnol 11 869
PubMedID: 29697197
Gene_locus related to this paper: asptn-q0ci40

Abstract

Feruloyl esterases (FAEs) are accessory enzymes for plant biomass degradation, which catalyse hydrolysis of carboxylic ester linkages between hydroxycinnamic acids and plant cell-wall carbohydrates. They are a diverse group of enzymes evolved from, e.g. acetyl xylan esterases (AXEs), lipases and tannases, thus complicating their classification and prediction of function by sequence similarity. Recently, an increasing number of fungal FAEs have been biochemically characterized, owing to their potential in various biotechnological applications and multitude of candidate FAEs in fungal genomes. However, only part of the fungal FAEs are included in Carbohydrate Esterase family 1 (CE1) of the carbohydrate-active enzymes (CAZy) database. In this work, we performed a phylogenetic analysis that divided the fungal members of CE1 into five subfamilies of which three contained characterized enzymes with conserved activities. Conservation within one of the subfamilies was confirmed by characterization of an additional CE1 enzyme from Aspergillus terreus. Recombinant A. terreus FaeD (AtFaeD) showed broad specificity towards synthetic methyl and ethyl esters, and released ferulic acid from plant biomass substrates, demonstrating its true FAE activity and interesting features as potential biocatalyst. The subfamily division of the fungal CE1 members enables more efficient selection of candidate enzymes for biotechnological processes.

ESTHER: Martinez-Martinez_2018_ACS.Chem.Biol_13_225
PubMedSearch: Martinez-Martinez 2018 ACS.Chem.Biol 13 225
PubMedID: 29182315
Gene_locus related to this paper: 9zzzz-a0a2k8jn75, 9zzzz-a0a2k8jt94, 9zzzz-a0a0g3fj44, 9zzzz-a0a0g3fh10, 9zzzz-a0a0g3fh03, 9bact-a0a1s5qkj8, 9zzzz-a0a0g3feh5, 9zzzz-a0a0g3fkz4, 9zzzz-a0a0g3fh07, 9zzzz-a0a0g3fh34, 9zzzz-a0a0g3fh31, 9bact-KY458167, alcbs-q0vqa3, 9bact-a0a1s5qki8, 9zzzz-a0a0g3feq8, 9zzzz-a0a0g3feh8, 9zzzz-a0a0g3fh19, 9bact-KY203037, 9bact-a0a1s5ql22, 9bact-a0a1s5qm34, 9bact-KY203034, 9bact-r9qzg0, 9bact-a0a1s5qly8, 9zzzz-a0a0g3fkz8, 9zzzz-a0a0g3feg9, 9zzzz-KY203033, 9zzzz-a0a0g3fes4, 9zzzz-a0a0g3fh42, 9bact-a0a1s5qlx2, 9zzzz-KY483651, 9bact-a0a1s5qmh4, 9zzzz-KY203032, 9zzzz-EH87, 9zzzz-a0a0g3fei1, 9zzzz-a0a0g3fet2, 9zzzz-KY483647, 9zzzz-EH82, 9zzzz-a0a0g3fe15, 9bact-KY203031, 9bact-t1w006, 9zzzz-a0a0g3fet6, 9bact-KY458164, geoth-g8myf3, 9bact-a0a1s5ql04, 9gamm-a0a1y0ihk7, 9bact-a0a1s5qly6, 9bact-a0a1s5qkg4, 9bact-a0a1s5qkm4, 9gamm-s5tv80, 9gamm-a0a0c4zhg2, 9zzzz-t1b379, 9gamm-KY483646, 9bact-KY458160, 9zzzz-a0a0g3fj57, 9gamm-s5t8349, 9arch-KY203036, 9bact-KY458168, 9zzzz-a0a0g3fes0, 9zzzz-t1be47, 9bact-KY458159, 9zzzz-a0a0g3fh39, 9bact-t1vzd5, 9prot-EH41, 9bact-Lip114, alcbs-q0vt77, 9bact-a0a1s5qke6, 9bact-a0a1s5qkf3, 9prot-SRP030024, 9gamm-s5t532, 9bact-a0a1s5qkl2, 9bact-a0a1s5qkk8, 9zzzz-KY203030, 9zzzz-t1d4I7, 9prot-KY019260, 9bact-a0a1s5qm38, 9arch-KY458161, 9prot-KY010302, 9zzzz-a0a0g3fl25, 9actn-KY010298, 9gamm-s5u059, 9bact-a0a1s5qmi7, 9bact-KY010297, 9bact-KY483642, 9bact-a0a1s5qkj1, 9bact-KY010299, 9bact-KY483648, alcbs-q0vtl7, 9bact-a0a1s5qf1, 9bact-a0a1s5qkg0, 9bact-a0a0h4tgu6, 9bact-MilE3, 9bact-LAE6, 9alte-MGS-MT1, 9bact-r9qzf7, 9gamm-k0c6t6, alcbs-q0vl36, alcbs-q0vlq1, alcbs-q0vq49, bacsu-pnbae, canar-LipB, canan-lipasA, geost-lipas, marav-a1u5n0, pseps-i7k8x5, staep-GEHD, symth-q67mr3, altma-s5cfn7, cycsp-k0c2b8, alcbs-q0vlk5, 9bact-k7qe48, 9bact-MGS-M1, 9bact-MGS-M2, 9bact-a0a0b5kns5, 9zzzz-a0a0g3fej4, 9zzzz-a0a0g3fj60, 9zzzz-a0a0g3fej0, 9zzzz-a0a0g3fj64, 9bact-a0a0b5kc16, 9zzzz-a0a0g3feg6, 9zzzz-a0a0g3feu6

Abstract

Esterases receive special attention because their wide distribution in biological systems and environments and their importance for physiology and chemical synthesis. The prediction of esterases substrate promiscuity level from sequence data and the molecular reasons why certain such enzymes are more promiscuous than others, remain to be elucidated. This limits the surveillance of the sequence space for esterases potentially leading to new versatile biocatalysts and new insights into their role in cellular function. Here we performed an extensive analysis of the substrate spectra of 145 phylogenetically and environmentally diverse microbial esterases, when tested with 96 diverse esters. We determined the primary factors shaping their substrate range by analyzing substrate range patterns in combination with structural analysis and protein-ligand simulations. We found a structural parameter that helps ranking (classifying) promiscuity level of esterases from sequence data at 94% accuracy. This parameter, the active site effective volume, exemplifies the topology of the catalytic environment by measuring the active site cavity volume corrected by the relative solvent accessible surface area (SASA) of the catalytic triad. Sequences encoding esterases with active site effective volumes (cavity volume/SASA) above a threshold show greater substrate spectra, which can be further extended in combination with phylogenetic data. This measure provides also a valuable tool for interrogating substrates capable of being converted. This measure, found to be transferred to phosphatases of the haloalkanoic acid dehalogenase superfamily and possibly other enzymatic systems, represents a powerful tool for low-cost bioprospecting for esterases with broad substrate ranges, in large scale sequence datasets.

ESTHER: Wefers_2017_J.Mol.Biol_429_2509
PubMedSearch: Wefers 2017 J.Mol.Biol 429 2509
PubMedID: 28669823
Gene_locus related to this paper: 9bace-b3c9d0.2, 9bace-b3cet1

Abstract

Arabinoxylans are constituents of the human diet. Although not utilizable by the human host, they can be fermented by colonic bacteria. The arabinoxylan backbone is decorated with arabinose side chains that may be substituted with ferulic acid, thus limiting depolymerization to fermentable sugars. We investigated the polypeptides encoded by two genes upregulated during growth of the colonic bacterium Bacteroides intestinalis on wheat arabinoxylan. The recombinant proteins, designated BiFae1A and BiFae1B, were functionally assigned esterase activities. Both enzymes were active on acetylated substrates, although each showed a higher ferulic acid esterase activity on methyl-ferulate. BiFae1A showed a catalytic efficiency of 12mM s(-1) on para-nitrophenyl-acetate, and on methyl-ferulate, the value was 27 times higher. BiFae1B showed low catalytic efficiencies for both substrates. Furthermore, the two enzymes released ferulic acid from various structural elements, and NMR spectroscopy indicated complete de-esterification of arabinoxylan oligosaccharides from wheat bran. BiFae1A is a tetramer based on the crystal structure, whereas BiFae1B is a dimer in solution based on size exclusion chromatography. The structure of BiFae1A was solved to 1.98A resolution, and two tetramers were observed in the asymmetric unit. A flexible loop that may act as a hinge over the active site and likely coordinates critical interactions with the substrate was prominent in BiFae1A. Sequence alignments of the esterase domains in BiFae1B with the feruloyl esterase from Clostridium thermocellum suggest that both domains lack the flexible hinge in BiFae1A, an observation that may partly provide a molecular basis for the differences in activities in the two esterases.

ESTHER: Zwane_2014_J.Ind.Microbiol.Biotechnol_41_1027
PubMedSearch: Zwane 2014 J.Ind.Microbiol.Biotechnol 41 1027
PubMedID: 24664515
Gene_locus related to this paper: asptu-FAEA

Abstract

The production of ferulic acid esterase involved in the release of ferulic acid side groups from xylan was investigated in strains of Aspergillus tubingensis, Aspergillus carneus, Aspergillus niger and Rhizopus oryzae. The highest activity on triticale bran as sole carbon source was observed with the A. tubingensis T8.4 strain, which produced a type A ferulic acid esterase active against methyl p-coumarate, methyl ferulate and methyl sinapate. The activity of the A. tubingensis ferulic acid esterase (AtFAEA) was inhibited twofold by glucose and induced twofold in the presence of maize bran. An initial accumulation of endoglucanase was followed by the production of endoxylanase, suggesting a combined action with ferulic acid esterase on maize bran. A genomic copy of the A. tubingensis faeA gene was cloned and expressed in A. niger D15#26 under the control of the A. niger gpd promoter. The recombinant strain has reduced protease activity and does not acidify the media, therefore promoting high-level expression of recombinant enzymes. It produced 13.5 U/ml FAEA after 5 days on autoclaved maize bran as sole carbon source, which was threefold higher than for the A. tubingensis donor strain. The recombinant AtFAEA was able to extract 50 % of the available ferulic acid from non-pretreated maize bran, making this enzyme suitable for the biological production of ferulic acid from lignocellulosic plant material.

ESTHER: Bauer_2006_Proc.Natl.Acad.Sci.U.S.A_103_11417
PubMedSearch: Bauer 2006 Proc.Natl.Acad.Sci.U.S.A 103 11417
PubMedID: 16844780
Gene_locus related to this paper: emeni-axe1, emeni-CUTI3, emeni-faec

Abstract

To facilitate analysis of plant cell wall polysaccharide structure and composition, we cloned 74 genes encoding polysaccharide-degrading enzymes from Aspergillus nidulans, Aspergillus fumigatus, and Neurospora crassa and expressed the genes as secreted proteins with C-terminal Myc and 6x His tags. Most of the recombinant enzymes were active in enzyme assays, and optima for pH and temperature were established. A subset of the enzymes was used to fragment polysaccharides from the irregular xylem 9 (irx9) mutant of Arabidopsis. The analysis revealed a decrease in the abundance of xylan in the mutant, indicating that the IRX9 gene, which encodes a putative family 43 glycosyltransferase, is required for xylan synthesis.

ESTHER: Crepin_2004_Appl.Microbiol.Biotechnol_63_567
PubMedSearch: Crepin 2004 Appl.Microbiol.Biotechnol 63 567
PubMedID: 14595525
Gene_locus related to this paper: neucr-FAED

Abstract

Feruloyl esterases constitute an interesting group of enzymes that have the potential for use over a broad range of applications in the agri-food industries. In order to expand the range of available enzymes, we have examined the presence of feruoyl esterase genes present in the genome sequence of the filamentous fungus Neurospora crassa. We have identified an orphan gene (contig 3.544), the translation of which shows sequence identity with known feruloyl esterases. This gene was cloned and the corresponding recombinant protein expressed in Pichia pastoris to confirm that the enzyme (NcFaeD-3.544) exhibits feruloyl esterase activity. Unusually the enzyme was capable of p-coumaric acid release from untreated crude plant cell wall materials. The substrate utilisation preferences of the recombinant enzyme place it in the recently recognised type-D sub-class of feruloyl esterase.