Function and mechanism of a low-molecular-weight peptide produced by Gloeophyllum trabeum in biodegradation of cellulose.
A special low-molecular-weight peptide named Gt factor, was isolated and purified via HPLC from the culture extract of the brown-rot fungus Gloeophyllum trabeum. It had high-affinity Fe(3+)-chelating ability and could reduce Fe(3+) to Fe(2+). In the presence of O(2), it could produce hydroxyl radicals HO*. The effects of Gt factor on cellulose degradation suggested that Gt factor could disrupt inter- and intra- hydrogen bonds in cellulose chains by a HO*-involved mechanism. This resulted in depolymerization of cellulose chains, which produced more reducing and non-reducing ends, thus making cellulose accessible for further degradation. This pathway was quite different from the hydrolytic processes driven by cellulases, and Gt factor might play an important role in the early stage of cellulose depolymerization by brown-rot fungi.
Wang
Wei
W
State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, People's Republic of China.
Gao
Pei Ji
PJ
D001487:Basidiomycota / Q000737:chemistry* / Q000145:classification / Q000201:enzymology; D001673:Biodegradation, Environmental; D002478:Cells, Cultured; D002482:Cellulose / Q000737:chemistry* / Q000378:metabolism; D005290:Ferric Compounds / Q000737:chemistry; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification* / Q000378:metabolism; D006860:Hydrogen Bonding; D006878:Hydroxides / Q000737:chemistry; D007501:Iron; D007502:Iron Chelating Agents / Q000737:chemistry; D008970:Molecular Weight; D010084:Oxidation-Reduction; D012680:Sensitivity and Specificity; D013045:Species Specificity; D013379:Substrate Specificity; D014934:Wood
D005290:Ferric Compounds; D005656:Fungal Proteins; D006878:Hydroxides; D007502:Iron Chelating Agents; D002482:Cellulose; C031356:hydroxide ion; D007501:Iron