The role of Cellobiose Dehydrogenases in Cellulose Biodegradation by Filamentous Fungi

纤维二糖脱氢酶在丝状真菌纤维素生物降解中的作用

• 批准号: 04660176
• 负责人: SAMEJIMA Masahiro
• 金额: $ 1.28万
• 依托单位: The University of Tokyo
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1992
• 资助国家: 日本
• 起止时间: 1992 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-04660176/
• 关键词: Cellulose; Cellobiose; Biodegradation; Dehydrogenase; Oxidase; Oxidoreductase; Wood rotting fungi; Phanerochaete chysosporium; 酸化環元酵素

The white rotting fungi, Phanerochaete chrysosporium, produces two types of cellobiose dehydrogenases, namely cellobiose oxidase (CBO) and cellobiose ; quinone oxidoreductase (CBQ), in the course of cellulose biodegradation. We have demonstrated that CBQ is derived from CBO by proteases co-exisisted in the culture medium of the later stage. Therefore, only CBO must be associated directly on cellulose biodegradation. I have revealed that the Fe (III) containing compound such as cytochrome c are more suitable electron acceptor than molecular oxygen, which was thought as a electron acceptor for CBO in the original article.CBO is unable to solubilize cotton cellulose by itself, but also there is no obvious synergistic effects between cellulases and CBO on solubilization of cotton cellulose. From this result, CBO seems not to have any important role in the solubilization of cellulose. This idea is confirmed by the very low activity for the oxidation of the reducing ends in polymeric cellulose compared with those for cellodexrins. Furthermore, the CBO adsorption of cellulose occurs on a part of the amorphous surface.From all these observations, the role of CBO in the cellulose biodegradation must be some important function of cellodextrin or cellobiose metabolism, for example, membrane transportation of metabolites or the linkage between metabolism of these compounds and energy production, rather than the decomposition of insoluble cellulose.

白色腐真菌黄孢原毛平革菌在降解纤维素的过程中产生两种纤维二糖氧化酶，即纤维二糖氧化酶（CBO）和纤维二糖醌氧化还原酶（CBQ）。我们已经证明CBQ是由CBO通过蛋白酶在后期培养基中共存而衍生的。因此，只有CBO必须与纤维素生物降解直接相关。发现含Fe（III）的化合物如细胞色素c比分子氧更适合作为CBO的电子受体，CBO本身不能溶解棉纤维素，而且纤维素酶与CBO之间也没有明显的协同增溶作用。从这个结果来看，CBO似乎在纤维素的增溶中没有任何重要作用。与纤维糊精相比，聚合纤维素中还原末端的氧化活性非常低，证实了这一观点。CBO在纤维素生物降解过程中的作用可能是纤维糊精或纤维二糖代谢的重要功能，如代谢产物的膜转运或这些化合物的代谢与能量产生之间的联系，而不是不溶性纤维素的分解。

项目成果

Masahiro Samejima: "A comparison of the catalytic propenties of cellobiose:quimed oxidoructase and cellobiose oxidasetion phanerochaets chryiosporium" Eur.J.Biochem.90. 171-181 (1992)

Masahiro Samejima：“纤维二糖催化特性的比较：quimed 氧化还原酶和纤维二糖氧化酶 phanerochaets chryiosporium”Eur.J.Biochem.90。

鮫島 正浩: "Phanerochaete chrysosporiumの生産するセロビオース脱水素酵素の性質とリグノセルロース生分解におけるその役割" 第37回リグニン討論会講演要旨集. 9-12 (1992)

Masahiro Samejima：“Phanerochaete chrysosporium 产生的纤维二糖脱氢酶的特性及其在木质纤维素生物降解中的作用”第 37 届木质素研讨会摘要 9-12（1992 年）。

Karl-Erik L.Eriksson: "Recent advances in fungal cellobiose oxidoreductases" Enzyme Microbial Technology. 15. 1002-1008 (1993)

Karl-Erik L.Eriksson：“真菌纤维二糖氧化还原酶的最新进展”酶微生物技术。

Karl-Erik L.Eriksson: "Recent advances in tungal cellobiose oxidoredustase" Enzyme Microbial Technology. 15. 1002-1008 (1993)

Karl-Erik L.Eriksson：“真菌纤维二糖氧化还原酶的最新进展”酶微生物技术。

Masahiro Samejima, and Karl-Erik L.Eriksson: "A comparison of the catalytic properties of cellobiose : quinone oxidoreductase and cellobiose oxidase from Phanerochaete chrysosporium :" Eur.J.Biochem.90. 171-181 (1992)

Masahiro Samejima 和 Karl-Erik L.Eriksson：“纤维二糖催化特性的比较：醌氧化还原酶和来自 Phanerochaete chrysosporium 的纤维二糖氧化酶：”Eur.J.Biochem.90。