Chlorination and cleavage of lignin structures by fungal chloroperoxidases.
Two fungal chloroperoxidases (CPOs), the heme enzyme from Caldariomyces fumago and the vanadium enzyme from Curvularia inaequalis, chlorinated 1-(4-ethoxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)-1,3-dihydroxypropane, a dimeric model compound that represents the major nonphenolic structure in lignin. Both enzymes also cleaved this dimer to give 1-chloro-4-ethoxy-3-methoxybenzene and 1,2-dichloro-4-ethoxy-5-methoxybenzene, and they depolymerized a synthetic guaiacyl lignin. Since fungal CPOs occur in soils and the fungi that produce them are common inhabitants of plant debris, CPOs may have roles in the natural production of high-molecular-weight chloroaromatics and in lignin breakdown.
Ortiz-Bermúdez
Patricia
P
Department of Bacteriology, University of Wisconsin, Madison, Wisconsin 53706, USA.
Srebotnik
Ewald
E
Hammel
Kenneth E
KE
D002711:Chloride Peroxidase / Q000502:physiology*; D019281:Dimerization; D005656:Fungal Proteins / Q000502:physiology*; D008031:Lignin / Q000737:chemistry / Q000378:metabolism*; D003904:Mitosporic Fungi / Q000201:enzymology*
D005656:Fungal Proteins; D008031:Lignin; D002711:Chloride Peroxidase