Bacillus amyloliquefaciensCotA degradation of the lignin model compound guaiacylglycerol-β-guaiacyl ether

Abstract

The cotA gene from Bacillus amyloliquefaciens MN-13 was cloned and expressed in Escherichia coli Transetta. Nucleotide sequence analysis showed an open reading frame of 1542 bp encoding a polypeptide comprised of 513 amino acids. The degradation of lignin model compounds by recombinant CotA was investigated by HPLC-MS with guaiacylglycerol-β-guaiacyl ether as the substrate. The compounds including guaiacol, 3-(4-hydro-3-methoxyphenyl)-3-oxo-propanol and 4-hydro-3-methoxy acetophenone detected by HPLC-MS verified the rupture of β-O-4 bond and oxidation Cα bond of guaiacylglycerol-β-guaiacyl ether by CotA. 4-vinylguaiacol and 1-(4-hydroxy-3-methoxyl phenyl)-1-(2-methoxyl) phenoxyl ethylene were first time found in the degradation products of guaiacylglycerol-β-guaiacyl ether. The appearance of 4-vinylguaiacol and 4-hydro-3-methoxy acetophenone confirmed the cleavage of Cβ-Cγ bond. 1-(4-hydroxy-3-methoxyl phenyl)-2-(2-methoxyl) phenoxyl ethylene was coupled by the radical reaction of 4-vinylguaiacol with guaiacol. Otherwise, no corresponding degradation product was found to give a proof of cleavage of Cα-Cβ bond in guaiacylglycerol-β-guaiacyl ether by CotA.

Characterization of Two Marine Lignin-Degrading Consortia and the Potential Microbial Lignin Degradation Network in Nearshore Regions

“…Meanwhile, the appearance of phenylpropane derivates such as 2-hydroxyisobutyric acid (retention time [RT], 8.55 min), acetophenone (RT, 13.09 min), 4-hydroxy-3-methoxyacetophenone (RT, 14.92 min), 2,6-dimethoxyhydroquinone (RT, 15.57 min), and 4,5-dimethoxy-2-[(E)-2-phenylethenyl] benzoic acid (RT, 15.90 min) in LIG-B sample clearly validated the lignin degradation by this consortium ( Table 1 ). Furthermore, the presence of acetophenone and acetophenone derivates found in LIG-B treated sample were also the indicative of β-O-4 bonds cleavage catalyzed by bacterial laccases in consortium LIG-B ( 34 ). Similarly, the disappearance of the aforementioned original low molecular-weight aromatics was accompanied by the appearance of new low-molecular-weight compounds (2-hydroxyisobutyric acid, RT, 8.55 min; 2,3-dimethylsuccinic acid, RT, 12.10 min; methylmalonic acid, RT, 12.41 min; hexadecanoic acid, RT, 19.18 min) in LIG-S sample ( Table 1 ).…”

Complete genome sequencing and investigation on the fiber-degrading potential of Bacillus amyloliquefaciens strain TL106 from the tibetan pig

“…Therefore, it is important to exploit a new source of cellulase. B. amyloliquefaciens is a cellulose-degrading bacterium that is rich in CAZymes genes and can produce a variety of cellulosedegrading enzymes [39]. A full understanding of the B. amyloliquefaciens genome will aid exploitation of cellulolytic enzymes produced by this organism.…”

Bacterial Laccases: Some Recent Advances and Applications

“…2.9 laccase (Navas et al 2019). Overall, the tested bacterial laccases catalyse the oxidative coupling of GGE units, but not the cleavage of the Cα-Cβ bond with the exception of B. amyloliquefaciens CotA that degraded GGE in a set of products identified as guaiacol, 4-vinylguaiacol, vanillin and other related compounds (Yang et al 2018). The presence of these compounds indicates that the main degradation pathway of GGE follows the oxidation of Cα and the cleavage of β-O-4 and Cβ-Cγ bonds, highlighting the potential of the B. amyloliquefaciens CotA laccase for lignin degradation.…”