title: The identification of and relief from Fe3+ inhibition for both cellulose and cellulase in cellulose saccharification catalyzed by cellulases from Penicillium decumbens.
abstract: Lignocellulosic biomass is an underutilized, renewable resource that can be converted to biofuels. The key step in this conversion is cellulose saccharification catalyzed by cellulase. In this work, the effect of metal ions on cellulose hydrolysis by cellulases from Penicillium decumbens was reported for the first time. Fe(3+) and Cu(2+) were shown to be inhibitory. Further studies on Fe(3+) inhibition showed the inhibition takes place on both enzyme and substrate levels. Fe(3+) treatment damages cellulases' capability to degrade cellulose and inhibits all major cellulase activities. Fe(3+) treatment also reduces the digestibility of cellulose, due to its oxidation. Treatment of Fe(3+)-treated cellulose with DTT and supplementation of EDTA to saccharification systems partially relieved Fe(3+) inhibition. It was concluded that Fe(3+) inhibition in cellulose degradation is a complicated process in which multiple inhibition events occur, and that relief from Fe(3+) inhibition can be achieved by the supplementation of reducing or chelating agents.
authors: State Key Laboratory of Microbial Technology, Shandong University, Jinan, Shandong 250100, China.
authors: Mingyu
authors: M
authors: Wang
authors: Ziming
authors: Z
authors: Mu
authors: Junli
authors: J
authors: Wang
authors: Shaoli
authors: S
authors: Hou
authors: Lijuan
authors: L
authors: Han
authors: Yanmei
authors: Y
authors: Dong
authors: Lin
authors: L
authors: Xiao
authors: Ruirui
authors: R
authors: Xia
authors: Xu
authors: X
authors: Fang
mesh_terms: D055162:Biocatalysis / Q000187:drug effects*; D050260:Carbohydrate Metabolism / Q000187:drug effects*; D002480:Cellulase / Q000037:antagonists & inhibitors* / Q000378:metabolism; D002482:Cellulose / Q000378:metabolism*; D004229:Dithiothreitol / Q000494:pharmacology; D004492:Edetic Acid / Q000494:pharmacology; D006861:Hydrogen Peroxide / Q000494:pharmacology; D006868:Hydrolysis / Q000187:drug effects; D007477:Ions; D007501:Iron / Q000494:pharmacology*; D010407:Penicillium / Q000187:drug effects / Q000201:enzymology*
chemical_list: D007477:Ions; D002482:Cellulose; D004492:Edetic Acid; D006861:Hydrogen Peroxide; D007501:Iron; D002480:Cellulase; D004229:Dithiothreitol