Streptomyces avermitilis CECT 3339 produces a ferulic acid esterase able to release ferulic acid from sugar beet pulp soluble feruloylated oligosaccharides

Abstract

: Sugar beet pulp (SBP) is a waste product of the sugar industry which is rich in ferulic acid. Few ferulic acid esterases (FAEs) that are capable of releasing ferulic acid from SBP or from SBP soluble feruloylated oligosaccharides (SFO-SBP) have been described. Streptomyces avermitilis CECT 3339 was grown in medium containing SBP or destarched wheat bran (DSWB) as the carbon source. FAE activity was evaluated in terms of the micro-organism's capacity to release ferulic acid from DSWB, SBP, SFO-DSWB and SFO-SBP. S avermitilis showed FAE activity in both media and was able to release ferulic acid from DSWB, SFO-DSWB and SFO-SBP. A comparison of the FAE activity detected in each medium indicated that diþ erent activities were induced by each type of carbon source.1999 Society of Chemical Industry ( Keywords : Streptomyces ; ferulic acid esterase ; sugar beet pulp ; wheat bran INTRODUCTIONFerulic acid esterase (FAE) is an enzyme capable of hydrolysing sugar-phenolic acid ester linkages. There has recently been considerable interest in FAE and its potential application in obtaining ferulic acid from agro-industrial waste materials such as those produced by the milling, brewing and sugar industries.1 The enzyme has been described in fungi and bacteria,2 but only four FAE producing streptomycetes have been previously reported : Streptomyces olivochromogenes, Streptomyces sp strains C-248 and C-254,3 and Streptomyces avermitilis.4Sugar beet pulp (SBP), a by-product of the sugar industry, is relatively rich in ferulic acid (approximately 1%). Very few FAEs, however, are capable of releasing ferulic acid from SBP5 or from the soluble feruloylated oligosaccharides which may be obtained from SBP (SFO-SBP).6,7 In fact, only one FAE capable of releasing ferulic acid from SBP or SFO-SBP has been described in streptomycetes.8 The aim of the present investigation was to evaluate the ferulic acid releasing FAE activity of S avermitilis CECT 3339 from SFO-SBP and other substrates when grown in the presence of destarched wheat bran (DSWB) or SBP.

The specificity and the ability ofAspergillusferuloyl esterase to releasep‐coumaric acid from complex cell walls of oat hulls

“…The molecular architecture of the cell walls of plants, and the enzymology of the degradation of the molecular structures found there, is a subject of great fundamental and practical importance 1. Cinnamoyl esterases, members of the carboxylic acid esterase class of enzymes, have been found to break the ester linkage between hydroxycinnamic acids and the attached sugar and release cinnamic acid(s) from cinnamic acid methyl esters,2, 3 feruloylated oligosaccharides,4, 5 and complex plant cell walls 6–9. These esterases act synergistically with other hydrolytic enzymes to facilitate complete degradation of the complex cell wall 10.…”

A non-modular type B feruloyl esterase from Neurospora crassa exhibits concentration-dependent substrate inhibition

“…Most of the FAEs have been shown to act synergistically with xylanases, cellulases and pectinases to break down complex plant cell wall carbohydrates [4,5]. Several members of the enzyme group have been purified and characterized from aerobic and anaerobic microbes that utilize plant cell wall carbohydrates [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20]. These enzymes have been classified as either type A or type B, depending on their substrate specificity for aromatic moieties.…”

“…The two major FAEs of Aspergillus niger have been the focus of several studies over the last decade. However, in recent years, our knowledge of the FAE family has expanded, with reports of new enzyme activities, the characterization of gene sequences and the first crystal structure [15][16][17][18][19]29]. Molecular analysis of FAE genes and their predicted protein sequences has revealed that many of these enzymes are modular, comprising a catalytic domain translationally fused to a non-catalytic cellulose-binding domain (CBD) [15,16,19,30], or are produced as monomeric enzyme units pre-designated to be assembled into longer cohesive units, such as the cellulosome of Clostridium [31].…”

Hydroxycinnamic acids and ferulic acid esterase in relation to biodegradation of complex plant cell walls

“…Ferulic acid esterase has been found to break the ester linkage between ferulic acid and the attached sugar, and so liberate ferulic acid from chemical model compounds -isolated feruloylated oligosaccharides Faulds et al 1995a, b;Williamson et al 1998a;Sancho et al 1999;Ferreira et al 1999) and from complex plant cell walls such as coastal bermudagrass ), wheat bran (Mackenzie and Bilous 1988;Williamson 1993, 1995;Relat et al 1994;Bartolomé et al 1995Bartolomé et al , 1997aFaulds et al 1995a;Kroon et al 1999), maize bran (Faulds et al 1995b), barley spent grain (Moore et al 1996;Bartolomé et al 1997a, b;Bartolomé and Gómez-Cordovés 1999;Sancho et al 1999), sugar beet pulp (Brézillon et al 1996;Ferreira et al 1999) and oat hulls (Yu et al 2000;2002a, b). Certain ferulic acid esterases have also been reported to be able to release ferulate dimers (Bartolomé et al 1997a), which play an important structural role in strengthening and cross-linking primary plant cell walls (Ishii 1997;Iiyama and Lam 2001).…”

“…This latter study on ferulic acid esterase from Aspergillus niger showed that only certain substitutions on the aromatic ring can be allowed in the hydroxycinnamic acid esters and this gives specificity to this enzyme. Ferreira et al (1999) found that a purified ferulic acid esterase from Streptomyces avernitilis was capable of releasing ferulic acid from sugar beet pulp. This enzyme was also reported to have different levels of activity on methyl ferulate and methyl ρ-coumarate (releasing ferulic and ρ-coumaric acids), but no activity was observed on methyl caffeate.…”