The metabolism of biphenyl structures in lignin by the wood-rotting fungus Coriolus versicolor

Abstract In the degradation of lignin by the wood-rotting fungus Coriolus versicolor , understanding the metabolism of biphenyl structure is one of the most important steps in elucidation of the depolymerization process. This study gave the first evidence of aromatic ring fission of a biphenyl structure type by C. versicolor . The degradation of biphenyl structures of lignin by this fungus occurred to a slight extent as a result of a non-specific system. This phenomenon was observed only in a medium in which phenol oxidase was actively produced by this fungus.     

云芝菌丝体多糖的分离纯化研究

利用热水抽提从云芝菌丝体中提取胞内多糖,初步纯化后,用DEAE-Sepharose CL-6B进行分离,从中分离出两个带电荷多糖组分即CVP-I和CVP-Ⅱ,对这两个组分分别用Sepharose CL-6B凝胶柱层析进行纯度鉴定,均出现单一峰,然后用紫外扫描发现这两个组分均出现蛋白多糖的特征吸收,从而可以判断这两个组分是蛋白结合多糖。     

Formation of new acetal linkages in the metabolism of syringaresinol structure of lignin by Coriolus versicolor

Abstract In the metabolism of a lignin substructure model; syringaresinol by wood-rot fungi ( Coriolus versicolor ), formation of a new type of acetal linkage was detected. The new acetal linkage was formed by the addition of a primary alcohol group of metabolites to the quinone methide of syringaresinol, and these reactions were catalyzed by the phenol oxidizing enzyme. This is a first evidence indicating the possibility that the acetal linkage was one of the intermonomer linkages in lignin or one of the linkages in lignin-carbohydrate complex in plant cell wall.     

彩绒革盖菌在猪粪堆肥中应用的初步研究

在以猪粪为原料的静态条垛堆肥的堆体试验中添加了彩绒革盖菌,研究其对堆肥发酵的影响。研究表明彩绒革盖菌在堆肥二次发酵时期有利于堆体温度的提升和保温,说明了在进入堆肥后期彩绒革盖菌对其中剩余的木质素等成分有很好的分解能力,有利于堆肥的腐熟和养分的释放,初步表明彩绒革盖菌是一株理想的堆肥发酵菌株。     

Desorption of zinc by extracellularly produced metabolites of Trichoderma harzianum, Trichoderma reesei and Coriolus versicolor

AIMS: To determine the role of fungal metabolites in the desorption of metals. METHODS AND RESULTS: Desorption of Zn from charcoal by three different fungi was compared against metal desorption with reverse osmosis water, a 0.1% Tween 80 solution and a 0.1 mol l(-1) CaCl(2) solution. All three fungal filtrates desorbed three times more Zn than either 0.1% Tween 80 or 0.1 mol l(-1) CaCl(2). Metal chelator production in Trichoderma harzianum and Coriolus versicolor was constitutively expressed while chelator production in Trichoderma reesei was induced by Zn. The presence of Zn inhibited the production of metal chelators by C. versicolor. Only C. versicolor was found to produce oxalic acid (a strong metal chelator). All fungi caused a marked decrease in pH, although this was not enough to explain the increased desorption of the metals by the different fungal filtrates. CONCLUSIONS: Metal chelation via organic acids and proteins are the main mechanisms by which the fungal filtrates increase zinc desorption. SIGNIFICANCE AND IMPACT OF THE STUDY: The results of this study explain why plants inoculated with T. harzianum T22 take up more metal from soil, than noninoculated plants while metabolites produced by fungi could be used for metal leaching from contaminated soils.     

云芝糖肽的液体发酵培养基的研究

通过液体发酵的摇瓶实验,考察碳源、氮源、碳氮比和乙醇浓度对云芝糖肽的产率影响,确定葡萄糖和玉米淀粉为适宜碳源,蛋白胨和黄豆饼粉为适宜氮源,合适的碳氮比为20∶1,适宜的乙醇体积分数为1.5%。采用以上的培养基进行70 L发酵罐进行扩大实验和10 t工业生产规模试验。发酵周期32 h,最终生物量达到13.0 g/L,云芝糖肽产率平均为2.21 g/L,与摇瓶发酵水平相当。此外工业实验还确定了云芝液体发酵的pH值、残糖浓度以及菌丝体形态等终点指标。     

Cloning and sequencing of a second laccase gene from the white-rot fungus Coriolus versicolor

A second laccase gene, CVLG1, was isolated from Coriolus versicolor. CVLG1 encodes a precursor protein of 526 amino acids which contains a 23-amino acid signal sequence, and the coding region is interrupted by 11 introns. The number of potential N-glycosylation sites in this product is 12 and the greatest among that of polyporales laccases. Moreover, this protein shares about 70% homology with other polyporales laccases. Genomic Southern analysis showed that C. versicolor laccases are encoded by more than four genes including CVLG1 and a transposed allele of this gene.     

云芝的化学成分及药理活性研究概况

通过文献检索对云芝的化学成分及药理活性方面进行了综述。研究发现云芝含甾体类、三萜类、有机酸类、生物碱类、葡糖醇类、蛋白质类、糖类、糖肽类等29个化合物,还含胞外黏性物质（ECMM）、胃蛋白酶抑制剂、真菌激发子、铁黏合螯合剂、环肽、18种人体所需的氨基酸和维生素B1、B2、B6及铜、铁、钾、锌等10多种人体所需的活性微量...     

彩绒革盖菌漆酶产酶条件研究

本文研究了碳源、氮源、愈创木酚、香兰素及培养条件对漆酶分泌的影响;结果表明,淀粉作碳源、干酷素作氮源有利于漆酶的分泌,适宜浓度的愈创木酚和香兰素等对漆酶的产生有一定的作用;pH在3.0－8.0的范围内对漆酶的分泌影响差别不大,培养温度,接种量、通气量对漆酶的分泌有较大影响。     

Coriolus versicolor催化酸性橙降解的研究

对利用白腐真菌Coriolus versicolor的菌丝球来催化染料酸性橙的降解作了报道。首先进行了不同初始浓度酸性橙的降解实验。在实验范围内,降解率随着初始浓度的增高而增高,平均降解率在91％左右。建立模型拟合了同一温度下不同初始浓度酸性橙降解的过程。初始浓度在20．99到101.6mg/L之间时,模型计算值与实验值大致吻合。考察了pH和温度对酸性橙降解的影响,发现菌丝球降解酸性橙的最适pH为6．0,温度以32℃左右为最佳。对补充了不同量碳源的酸性橙溶液进行重复分批降解实验表明,碳源的补充对重复分批降解是必不可少的。在重复过程中,降解率呈下降趋势。但在降解染料的同时添加适量的葡萄糖可以使菌丝的使用寿命显著延长。     

一株新分离的云芝栓孔菌Z-1应用于木质素降解及染料脱色

木质素是一种非结晶性的复杂三维网状酚类高分子聚合物,被认为是木质纤维素生物质抗降解的天然屏障.探索并开发高效降解木质素的微生物资源已成为近些年来的研究焦点.本研究对新分离的一株具有潜在木质素降解能力的菌株Z-1开展了系列研究.首先通过形态学和系统发育分析将菌株Z-1鉴定为云芝栓孔菌Trametes versicolor...     

Transformation of 2,4,6-trichlorophenol by the white rot fungi Panus tigrinus and Coriolus versicolor

The toxicity of thirteen isomers of mono-, di-, tri- and pentachlorophenols was tested in potato-dextrose agar cultures of the white rot fungi Panus tigrinus and Coriolus versicolor. 2,4,6-Trichlorophenol (2,4,6-TCP) was chosen for further study of its toxicity and transformation in liquid cultures of these fungi. Two schemes of 2,4,6-TCP addition were tested to minimize its toxic effect to fungal cultures: stepwise addition from the moment of inoculation and single addition after five days of growth. In both cases the ligninolytic enzyme systems of both fungi were found to be responsible for 2,4,6-TCP transformation. 2,6-Dichloro-1,4-hydroquinol and 2,6-dichloro-1,4-benzoquinone were found as products of primary oxidation of 2,4,6-TCP by intact fungal cultures and purified ligninolytic enzymes, Mn-peroxidases and laccases of both fungi. However, primary attack of 2,4,6-TCP in P. tigrinus culture was conducted mainly by Mn-peroxidase, while in C. versicolor it was catalyzed predominantly by laccase, suggesting a different mode of regulation of these enzymes in the two fungi.     

彩绒革盖菌固体发酵生产木质素酶工艺优化研究*

采用均匀设计U15(5^8)和双温度培养法进行彩绒革盖菌固体发酵生产木质素酶,对漆酶、愈创木酚酶、多酚氧化酶的活力进行回归分析。结果表明：应用双温度培养法进行彩绒革盖菌固体发酵生产木质素酶时,在自然补给氧气,培养基pH自然(约6．5),并保持环境湿度约60％的条件下,20d是适宜的发酵周期;玉米浆、麸皮、(NH4)2SO4、水分适宜作为固体培养基的成分;少量的Tween-80有利于木质素酶的生产。     

应用Coriolus vericolor 菌丝球脱色染料及印染废水的研究

对白腐真菌（Coriolus vericolor）产生漆酶进行了研究。发现该菌产漆酶的最适初始pH值为4．5。提高微量元素浓度或添加藜芦醇都可使C.versiclor的产酶能力增加,添加Tween80会有一定的抑制作用。采用C.versicolor菌丝球进行重复分批产酶试验,结果表明菌丝球的稳定性很好,同一批菌丝球可连续利用14次,平均每批酶活力可保持在6．72U／mL,产酶能力优于聚氨酯泡沫固定化菌丝。将粗酶液用要料的脱色降解试验,在酶活力为3．3IU／mL,酸性橙浓度为500mg/L条件下,经过24h反应,脱色率达到98．5％;对含弱酸大红和卡布龙红的印染废水进行脱色试验,脱色率也达到了93％。     

Improvement in thermal stability and reactivity of pyranose oxidase from Coriolus versicolor by random mutagenesis

A mutant producing a pyranose oxidase, which has a higher thermal stability and lower Km values for d-glucose and 1,5-anhydro-d-glucitol than those of the wild type enzyme, was obtained. A single amino acid substitution, Lys for Glu at position 542, had occurred. This altered enzyme, E542K, was not only stable at 55°C, which was 5°C higher than the wild-type enzyme, but was stable in alkaline solution at pH 8.0–11.0. Km values of E542K for d-glucose and 1,5-anhydro-d-glucitol were 0.7 mM and 14.3 mM, respectively, in contrast with 1.4 mm and 35.3 mM for the wild-type enzyme. A little effect was observed in kcat values, and improvement in reactivity was mainly due to the decreases in Km values. This altered pyranose oxidase is useful for food analysis and diagnosis.     

碳素和氮素对Coriolus versicolor胞外酶分泌的影响

采用单因子相互比较法研究了不同碳素和氮素对彩绒革盖菌胞外漆酶,愈创木酚氧化酶,多酚氧化酶,锰过氧化物酶等木素降解酶分泌的影响,结果淀粉作碳源,干酪素作氮源有利于漆酶的分泌,麦芽粉作碳源,酵母膏作氮源有利于愈创木酚氧化酶和多酚氧化酶的分泌,淀粉作碳源,玉米粉作氮源有利于锰过氧化物酶的分泌。     

Laccase activity in lignin degradation by Coriolus versicolor in vivo and in vitro studies

Abstract Laccase activity in ligninolytic cultures of Coriolus versicolor was inhibited by the addition of antibodies. The degree and rate of lignin degradation was unaffected by this inhibition in comparison with cultures which had normal laccase activity. Although experiments in vitro showed that milled wood lignin was depolymerised by laccase in the presence of hydrogen peroxide, and that this reaction was inhibited by antibody, it is concluded that this degradative reaction was not the function of laccase in vivo.     

Metabolism of non-phenolic diarylpropane lignin substructure model compound by Coriolus versicolor

Abstract A lignin substructure model, 1-(4-ethoxy-3,5-dimethoxyphenyl)-2-(4-ethoxy-3-methoxyphenyl)-propane-1,3-diol(I), was actively metabolized by a white-rot fungus Coriolus versicolor in low nitrogen stationary cultures favouring the ligninolytic activity in the fungus. Cleavage of the dimer I between C_α and C_β of the propanoid side chain was the major degradative reaction by the fungus.     

碳源和氮源对彩绒革盖菌液体发酵合成漆酶的影响

研究了碳源、氮源对彩绒革盖菌液体发酵合成漆酶的影响。结果表明,在所选的几种碳、氮源中,麸皮为试验菌株合成漆酶的较好碳源;酵母浸膏、酒石酸铵、蛋白胨均是比较理想的氮源。不同的碳氮比对彩绒革盖菌漆酶的产量有着显著的影响,高碳高氮是其生产漆酶的最佳条件。在适宜的培养条件下该菌株能合成高活力的漆酶,其酶活力可达298 U/mL以上,产酶周期为6~7 d。