Biomass-to-bio-products application of feruloyl esterase from Aspergillus clavatus

Abstract

The structural polysaccharides contained in plant cell walls have been pointed to as a promising renewable alternative to petroleum and natural gas. Ferulic acid is a ubiquitous component of plant polysaccharides, which is found in either monomeric or dimeric forms and is covalently linked to arabinosyl residues. Ferulic acid has several commercial applications in food and pharmaceutical industries. The study herein introduces a novel feruloyl esterase from Aspergillus clavatus (AcFAE). Along with a comprehensive functional and biophysical characterization, the low-resolution structure of this enzyme was also determined by small-angle X-ray scattering. In addition, we described the production of phenolic compounds with antioxidant capacity from wheat arabinoxylan and sugarcane bagasse using AcFAE. The ability to specifically cleave ester linkages in hemicellulose is useful in several biotechnological applications, including improved accessibility to lignocellulosic enzymes for biofuel production.

Biotransformation of ferulic acid to protocatechuic acid by Corynebacterium glutamicum ATCC 21420 engineered to express vanillate O-demethylase

“…FA can be extracted using ferulic acid esterases (FAEs) from plant biomass (Gopalan et al 2015). FA is extracted from wheat bran using Penicillium funiculosum FAE (Kroon et al 2000), from corn bran using Neosartoryaspinosa crude FAE (Shin et al 2006), and from wheat arabinoxylan using Aspergillus clavatus FAE (Damasio et al 2013). Further, FA is extracted from sugar beet pulp using a crude extract of Aspergillus niger (Bonnin et al 2002) and from autoclaved maize bran using A. niger FAE (Benoit et al 2006).…”

Genomics Review of Holocellulose Deconstruction by Aspergilli

“…The active site cavity is confined by a lid, analogous to the case in lipases, and by a loop that confers plasticity to the substrate-binding site (221). Feruloyl esterases were initially classified by aromatic functional categories (222,223), and later the classification was extended to subfamilies A, B, C, and D, based on primary amino acid sequence similarity and substrate specificity against four model substrates, i.e., methyl 3-methoxy-4-hydroxycinnamate (MFA), methyl 3,4-dihydroxycinnamate (MCA), methyl 4-hydroxycinnamate (MpCA), and methyl 3,5-dimethoxy-4-hydroxycinnamate (MSA) (224,225). Table 10 shows that feruloyl esterases are represented in variable copy numbers in all aspergilli, in some cases showing much more than 2 copies (3 copies in A. clavatus, 8 in A. flavus and A. terreus, 10 in A. oryzae, and 11 copies in A. niger).…”

Ultraviolet-absorbing compounds from the cell walls of an aquatic liverwort are more efficiently extracted by alkaline than by enzymatic digestion

“…This may be related to the fact that xyloglucan, an important component of hemicellulose, appears to be present at low concentration in bryophytes (Popper & Fry, 2003), and thus its degradation might not be especially relevant to the release of UVACs. In contrast, hemicellulose breakdown liberates important amounts of some specific UVACs, such as ferulic acid, in some tracheophyte materials (wheat arabinoxylan and sugarcane bagasse: Damasio et al, 2013). In future, other enzymes could be investigated for their ability to release UVACs more effectively from the distinctive cell walls of bryophytes, and thus to improve the extraction of UVACs.…”

“…In future, other enzymes could be investigated for their ability to release UVACs more effectively from the distinctive cell walls of bryophytes, and thus to improve the extraction of UVACs. In particular, esterases that can release efficiently specific UVACs, such as HCAs, may represent promising candidates (Kuhnel et al, 2012;Damasio et al, 2013).…”