The Aspergillus niger faeB gene encodes a second feruloyl esterase involved in pectin and xylan degradation and is specifically induced in the presence of aromatic compounds

Abstract

The faeB gene encoding a second feruloyl esterase from Aspergillus niger has been cloned and characterized. It consists of an open reading frame of 1644 bp containing one intron. The gene encodes a protein of 521 amino acids that has sequence similarity to that of an Aspergillus oryzae tannase. However, the encoded enzyme, feruloyl esterase B (FAEB), does not have tannase activity. Comparison of the physical characteristics and substrate specificity of FAEB with those of a cinnamoyl esterase from A. niger [Kroon, Faulds and Williamson (1996) Biotechnol. Appl. Biochem. 23, 255-262] suggests that they are in fact the same enzyme. The expression of faeB is specifically induced in the presence of certain aromatic compounds, but not in the presence of other constituents present in plant-cell-wall polysaccharides such as arabinoxylan or pectin. The expression profile of faeB in the presence of aromatic compounds was compared with the expression of A. niger faeA, encoding feruloyl esterase A (FAEA), and A. niger bphA, the gene encoding a benzoate-p-hydroxylase. All three genes have different subsets of aromatic compounds that induce their expression, indicating the presence of different transcription activating systems in A. niger that respond to aromatic compounds. Comparison of the activity of FAEA and FAEB on sugar-beet pectin and wheat arabinoxylan demonstrated that they are both involved in the degradation of both polysaccharides, but have opposite preferences for these substrates. FAEA is more active than FAEB towards wheat arabinoxylan, whereas FAEB is more active than FAEA towards sugar-beet pectin.

Association of tannase-producing Staphylococcus lugdunensis with colon cancer and characterization of a novel tannase gene

“…28 No amino acid sequence predicted from ORF3 exhibited signifi cant homology to those of published genes, including tannase. 29,30 To identify the gene for tannase, we constructed deletion derivatives of pTZtan18 and subcloned ORF2 and ORF3; production of tannase in the strain carrying the plasmid was tested (Fig. 1).…”

Plant-Polysaccharide-Degrading Enzymes from Basidiomycetes

“…The molecular masses of FAEs of the white rot fungi P. eryngii and P. sapidus are 67 kDa and 55 kDa, respectively, which are higher than those of the FAEs of A. awamori (35 kDa) (176) and A. niger FaeA (36 kDa) (177,178) but lower than that of A. niger FaeB (74 kDa) (178). P. eryngii FaeA (PeFaeA) and P. sapidus Est1 are 93% similar at the amino acid sequence level (173).…”

Regulation of the α-glucuronidase-encoding gene (aguA) from Aspergillus niger

“…Work performed since then on the effects of CREA on xylanolytic genes has demonstrated that carbon source concentrations of around 1% cause significant reductions in expression levels due to CREAmediated repression (de Vries et al 1999). In addition, a recent study demonstrated that glucuronic acid causes CREA-mediated repression of the induction by ferulic acid of feruloyl esterase-encoding genes from A. niger (de Vries et al 2002). Therefore, in this study, lower carbon source concentrations were used and it is thus not surprising that no aguA expression was previously detected in a wild-type strain using 1% glucuronic acid.…”