Trypsin-like proteinases and trypsin inhibitors in fruiting bodies of higher fungi

The activity of trypsin-like proteinases and trypsin inhibitors was measured in fruiting bodies of various species of basidial fungi (Basidiomycetes). Fruiting bodies of all fungi contained these enzymes, with the exceptions of polypore (Coriolus versicolor (Fr.) Karst) and hedgehog fungus (Hericium erinaceus (Fr.) Quel), belonging to the families Polyporaceae and Hericiaceae, respectively, in which the enzyme activities were barely detectable. The activity of trypsin-like proteinases was the highest in fruiting bodies of Boletaceae and Agaricaceae. Fruiting bodies of all fungi contained trypsin inhibitors. The highest activity of trypsin inhibitors was detected in basidiomycetes of the families Boletaceae, Agaricaceae, and Pleurotaceae, including Boletus castanus (Fr.) Karst, orange-cap boletus (Leccinum aurantiacum (Fr.) Sing), and brown-cap boletus (Leccinum melanum (Fr.) Karst).     

Taxonomic and Ecological Structure of Basidial Macromycetes Biota in Polar Deserts of the Northern Hemisphere

The results of a study of the more than century-long history of taxonomic and ecological structures of basidial macromycete biota in polar deserts of the Northern Hemisphere are discussed. Nowadays, 77 species of macromycetes are known from this region, 40 species of which are agaricoid fungi, 30 are aphyllophoroid, and 7 are gasteromycetes. The highest number of species is known for the Franz Josef Land archipelago and Severanya Zemlya. All the identified species of agaricoid and 86% of gasteroid fungi are native representatives from extremely high latitudes collected under natural conditions, whereas 80% of the aphyllophoroid fungi are alien elements. All alien species are able to exist in the region exclusively in human-modified habitats, colonizing anthropogenic woody and grass substrates, and they disappear with the depletion of these resources. Despite the existence of mycobiota at the limit of the global thermal gradient, a specific species complex of macromycetes that does not occur anywhere in the world is formed here. Symbiotrophic species (basidial lichens and mycorrhiza-formers) are the most adaptable to such extreme conditions. General features of the organization with Antarctic mycobiota are established. The possibility that new species will appear in the region is discussed in connection with the intensification of human economic activity and global climate change.     

Effect of culture medium composition on the activity of extracellular lectins of Lentinus edodes

The time course of lectin production in culture liquid of the basidial fungus Lentinus edodes strain F-249 in different media under the conditions of submerged culture was studied. The activity of agglutinins depended on the ratio between carbon and nitrogen sources and pH of culture medium. The activity of lectin in culture medium was maximal when the fungus was grown in a medium containing L-arabinose as a source of carbon and L-asparagine as a source of nitrogen (C : N ratio, (9.5-12): 1)) on the day 15-18 of culturing at pH 8-9.     

Trypsin-Like Proteinases and Trypsin Inhibitors in Fruiting Bodies of Higher Fungi

The activity of trypsin-like proteinases and trypsin inhibitors was measured in fruiting bodies of various species of basidial fungi (Basidiomycetes). Fruiting bodies of all fungi contained these enzymes, with the exceptions of polypore (Coriolus versicolor (Fr.) Karst) and hedgehog fungus (Hericium erinaceus (Fr.) Quel), belonging to the families Polyporaceae and Hericiaceae, respectively, in which the enzyme activities were barely detectable. The activity of trypsin-like proteinases was the highest in fruiting bodies of Boletaceae and Agaricaceae. Fruiting bodies of all fungi contained trypsin inhibitors. The highest activity of trypsin inhibitors was detected in basidiomycetes of the families Boletaceae, Agaricaceae, and Pleurotaceae, including Boletus castanus (Fr.) Karst, orange-cap boletus (Leccinum aurantiacum (Fr.) Sing), and brown-cap boletus (Leccinum melanum (Fr.) Karst).     

Thiomorpholine transformation by the fungus Bjerkandera adusta

A screening of lignin-degrading basidial fungi that can grow in the presence of thiomorpholine derivatives (the mixture of 1,4-perhydrothiazines) has been performed. Strain Bjerkandera adusta VKM F-3477 was shown to have the maximal rate of growth in the presence of these compounds, and its capacity for thiomorpholine degradation was studied. The methods of quantitative analysis of thiomorpholine and its degradation products on the basis of thin layer chromatography and high-performance liquid chromatography were developed. It was shown that the B. adusta strain did not utilize thiomorpholine as a carbon source but transformed it into thiomorpholine sulfoxide that accumulated in the medium. Mn peroxidase produced by B. adusta in the course of thiomorpholine transformation is not directly involved in its oxidation.     

Conversion of polychlorophenols by laccases with 1-hydroxybenzotriazole as a mediator

The action of purified laccase from the basidial fungi Cerrena unicolor and Trametes sp. on 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) was studied, including reactions involving I-hydroxybenzotriazole as a mediator. Oxidation of 2,4,6-TCP by laccase without the mediator yielded 2,6-dichlorobenzoquinone as a primary conversion product, whereas PCP was not oxidized. Products of further conversion of 2,4,6-TCP and PCP formed with the presence of the mediator.     

Study of Nutritional and Environmental Factors Affecting the Fruiting Competence of Rhizoctonia solani AG-1

The study of nutritional, physiological and physical factors affecting basidiospore development in Rhizoctonia solani evidenced the critical influence of the physiological state of the mycelium subjected to a nutritional stress for fruiting induction. Comparison of four preculture media allowed identification of the optimal nutrient status provided by glucose, yeast extract and bacto-peptone, for subsequent basidial differentiation on a starved water agar medium. While variations of glucose and yeast extract concentrations are not determinant for basidial differentiation, the breakdown observed with a low bactopeptone concentration underscores a major role for the nitrogen content which however should be considered in a balance with the carbon source. The basidial differentiation was shown: (i) to increase as the age of the preculture used to inoculate water agar increases; (ii) to be stimulated by a dark/light regime, and (iii) to be induced and increased by a cold temperature shock (8^oC) when the mycelium was derived from young precultures. The effect of the cold temperature shock indicates that the preculture conditions can induce long-term physiological modifications in the myccelia. While the fruiting response to nutritional factors is similar whatever the strain used the response to environmental factors depends mainly on the genotype of the strains.     

Cellulase and xylanase activities in higher basidiomycetes.

Extracellular carboxymethylcellulase, xylanase, beta-glucosidase, and beta-xylosidase activities of four cultures of higher basidial fungi were studied in relation to the source of carbon in the nutrient medium. It was shown that beta-glucosidases and beta-xylosidases of all basidiomycetes and cellulases and xylanases of Pholiota aurivella IBR437 and Gloeophyllum saepiarium IBR155, the causal agents of wood brown rot, are constitutive enzymes; however, their activities depend on the source of carbon in the growth medium. Cellulases and xylanases of Coriolus pubescens IBR663 and Lentinus tigrinus IBR100 degrading wood through white rot are inducible enzymes. The synthesis of cellulases and xylanases was induced upon fungal growth on media containing crystalline cellulose and plant raw materials; carboxymethylcellulose and xylan were less effective. The induction of C. pubescens IBR663 cellulase and xylanase was observed when avicel was added to the culture growing on a mannitol-containing medium. Glucose at a concentration of 0.2-0.8% caused catabolite repression of C. pubescens IBR663 cellulase and xylanase. After utilization of glucose, leading to a decrease in its concentration below 0.1%, the synthesis of enzymes was resumed. These data indicate that the synthesis of cellulases and xylanases in the examined macromycetes is under common regulatory control.     

根际圈在污染土壤修复中的作用与机理分析

根际圈以植物根系为中心聚集了大量的生命物质及其分泌物,构成了极为独特的“生态修复单元”。本文叙述了根在根际圈污染土壤修复中的生理生态作用,富集、固定重金属,吸收、降解有机污染物等功能;菌根真菌对根际圈内重金属的吸收、屏障及螯合作用,对有机污染物的降解作用;根际圈内细菌对重金属的吸附与固定,对有机污染物的降解作用以及根际圈真菌和细菌的联合修复作用等,同时对可能存在的机理进行了分析,认为根际圈对污染土壤的修复作用是植物修复的重要组成部分和主要理论基础之一,并指出利用重金属超富集植物修复重金属污染土壤具有广阔的应用前景;筛选对水溶性有机污染物高吸收富集及其根 发泌能力强的特异植物,同时接种利于有机污染物降解的专性或非专性真菌和细菌可能会成为有机污染土壤植物修复研究的重要方向之一。     

Biodegradation of Polyester Polyurethane by Endophytic Fungi

Bioremediation is an important approach to waste reduction that relies on biological processes to break down a variety of pollutants. This is made possible by the vast metabolic diversity of the microbial world. To explore this diversity for the breakdown of plastic, we screened several dozen endophytic fungi for their ability to degrade the synthetic polymer polyester polyurethane (PUR). Several organisms demonstrated the ability to efficiently degrade PUR in both solid and liquid suspensions. Particularly robust activity was observed among several isolates in the genus Pestalotiopsis, although it was not a universal feature of this genus. Two Pestalotiopsis microspora isolates were uniquely able to grow on PUR as the sole carbon source under both aerobic and anaerobic conditions. Molecular characterization of this activity suggests that a serine hydrolase is responsible for degradation of PUR. The broad distribution of activity observed and the unprecedented case of anaerobic growth using PUR as the sole carbon source suggest that endophytes are a promising source of biodiversity from which to screen for metabolic properties useful for bioremediation.     

The effects of transported Asian dust on the composition and concentration of ambient fungi in Taiwan

This study was conducted to evaluate the effects of transported Asian dust and other environmental parameters on the levels and compositions of ambient fungi in the atmosphere of northern Taiwan. We monitored Asian dust events in Taipei County, Taiwan from January 2003 to June 2004. We used duplicate Burkard portable air samplers to collect ambient fungi before, during, and after dust events. Six transported Asian dust events were monitored during the study period. Elevated concentrations of Aspergillus (A. niger, specifically), Coelomycetes, Rhinocladiella, Sporothrix and Verticillium were noted (p < 0.05) during Asian dust periods. Botryosporium and Trichothecium were only recovered during dust event days. Multiple regression analysis showed that fungal levels were positively associated with temperature, wind speed, rainfall, non-methane hydrocarbons and particulates with aerodynamic diameters ≤10 μm (PM₁₀), and negatively correlated with relative humidity and ozone. Our results demonstrated that Asian dust events affected ambient fungal concentrations and compositions in northern Taiwan. Ambient fungi also had complex dynamics with air pollutants and meteorological factors. Future studies should explore the health impacts of ambient fungi during Asian dust events, adjusting for the synergistic/antagonistic effects of weather and air pollutants.     

Conversion of polychlorophenols by laccases with 1-hydroxybenzotriazole as a mediator

The action of purified laccase from the basidial fungi Cerrena unicolor and Trametes sp. on 2,4,6-trichlorophenol (2,4,6-TCP) and pentachlorophenol (PCP) was studied, including reactions involving 1-hydroxybenzotriazole as a mediator. Oxidation of 2,4,6-TCP by laccase without the mediator yielded 2,6-dichlorobenzoquinone as a primary conversion product, whereas PCP was not oxidized. Products of further conversion of 2,4,6-TCP and PCP formed with the presence of the mediator.     

丛枝菌根对有机污染土壤的修复作用及机理

丛枝菌根(AM)是丛枝菌根真菌(AMF)与植物根系相互作用的互惠共生体,能改良土壤结构,增强植物抗性.自然界中已知的AMF有170多种,分布广泛,且可与大多数植物共生.利用AM修复有机污染土壤正成为一个崭新的研究方向.本文综述了AM对多环芳烃、酞酸脂、石油和农药等一些典型有机污染物污染土壤的修复作用.AM修复有机污染土壤的机理主要包括:AMF代谢有机污染物;AM分泌酶,降解污染物;AM影响根系分泌作用,并促进根际微生物对有机污染物的降解;AMF宿主植物吸收积累污染物.AM修复研究中,高效AMF的筛选、复合菌种效应、土壤老化、AM作用下植物对有机污染物的吸收积累等几方面仍有待于深入研究.     

环境污染物对丛枝菌根(AM)形成及功能的影响

丛枝菌根(AM)具有植物和微生物的双重特性,在污染土壤修复中受到越来越多的重视.AM在修复污染土壤的同时,也深受污染物毒害的影响,从而降低AM在污染土壤修复中的作用.如何减少环境污染物对AM的不利影响,是AM应用中需要考虑的问题.从有机和无机污染物角度, 综述了不同污染物对AM形成及功能的影响,并分析了可能的影响机理.大量研究表明,无论是有机污染物还是无机污染物,都会对AM的结构、形成和功能产生破坏性影响,主要表现在孢子萌发、侵染率、菌丝伸长受抑制等.有机污染物可能通过影响光合产物向AM真菌的分配, 间接影响AM真菌的活性,而重金属则通过抑制AM真菌活性, 直接对其产生影响.     

Effect of culture medium composition on the activity of extracellular lectins of <Emphasis Type="Italic">Lentinus edodes</Emphasis>

The time course of lectin production in culture liquid of the basidial fungus Lentinus edodes strain F-249 in different media under submerged culture conditions was studied. The activity of agglutinins depended on the ratio between carbon and nitrogen sources and the pH of the culture medium. The lectin activity in culture medium was maximal when the fungus was grown in a medium containing L-arabinose as a source of carbon and L-asparagine as a source of nitrogen (C:N ratio, (9.5–12):1) on day 15–18 of culturing at pH 8.0–9.0.Translated from Prikladnaya Biokhimiya i Mikrobiologiya, Vol. 41, No. 2, 2005, pp. 200–203.Original Russian Text Copyright © 2005 by Tsivileva, Nikitina, Garibova.     

Detection of mutagenic activity in particulate air pollutants.

Ames's strains of Salmonella typhimurium were used to evaluate the mutagenic activity of airbone particulate materials collected at six different points in the industrial area of Ohmuta and the residential area Fukuoka. Tests were done in presence of rat-liver S-9 fraction isolated from rats that had been treated with Aroclor 1254. When the number of revertant colonies per plate was plotted against the amount of methanol extract of particulate air pollutants, using strain TA98, approximately linear relationships were observed for active samples. Generally, mutagenic activity of the samples increased in proportion to the density of air pollutants. In our system, 38--349 microng of methanol extract, from 0.225--4.51 m3 of air from the factory districts in Ohmuta City gave 100 his+ revertants per plate. On the other hand, 54--2300 microng of air pollutants, from 1.29--14.1 m3 of air from the residential districts in Fukuoka City, gave a comparable activity. Every sample from each area had mutagenic activity. Chemicals in air pollutants were fractionated by alumina column chromatography and identified by gas chromatography and mass spectrometry. More than 28 compounds, including 12 unknown substances were identified as polycyclic hydrocarbons. Twelve of these compounds are already known to be carcinogens and to induce reversions to histidine independence in strain TA98 of Salmonella.     

Comparative characteristics of the bacterial complex in the hyphosphere of basidial macromycetes

A comparison of bacterial complexes from the hyphosphere of 33 basidial macromycetes species (typical representatives of forest biogeocenosis) has been studied. In addition, their similarity to the control soil bacterial complex has been investigated. The changes in the total number of bacteria, the proportion of the potentially viable cell number of saprotrophic bacteria, the structure of the bacterial saprotrophic complex, and the ratio of different phylogenetic groups of prokaryotes in the hyphosphere of basidial macromycetes were determined. A marked species-specific nature of the influence of basidial macromycetes on soil bacterial complexes was specified. Similarities in the saprotrophic bacterial complexes of aphyllophoroid and gasteroid in the hyphosphere of Basidiomycota were revealed.     

一株产漆酶土壤真菌F-5的分离及土壤修复潜力

漆酶因可氧化许多种有机污染物,在土壤污染修复方面的应用潜力受到广泛重视。筛选具有较高漆酶活性的土壤真菌,可以为污染土壤修复提供生物资源。通过培养基中愈创木酚颜色反应,从土壤中筛选获得1株真菌菌株F-5。18S rRNA基因序列显示该菌株属于巨座壳科(Family Magnaporthaceae)。单因素试验和正交试验结果显示,蔗糖和蛋白胨分别是最有利于该菌产漆酶的碳源和氮源。在适当培养条件下,真菌F-5培养液酶活性可达4033U/L,表现出该菌具有较强的产漆酶能力。在多环芳烃(PAHs)污染土壤的生物修复中,真菌F-5可使土壤中苯并(a)芘、二苯并(a,h)蒽等高环、高毒性多环芳烃降解,并使土壤多环芳烃毒性当量大幅降低。因此,真菌F-5适合修复PAHs污染土壤。     

景观生态学在大气污染研究中的应用

快速城市化和工业化进程造成了一系列大气污染问题,亟需在宏观尺度上解析大气污染时空分布规律。景观生态学关注格局与过程耦合,景观"源汇"理论可对应解析大气污染物的源与汇效应,将景观生态学的理论与方法引入大气污染研究中已成为解决当前区域发展与大气污染权衡的有效途径。从景观生态学视角辨识了景观与大气污染物的源汇关系,系统梳理了景观格局与大气污染的定量关系,指出当前景观格局指标仍需进一步完善以表征大气污染时空分布特征,而高质量大气污染物时空数据的缺乏是限制景观格局与大气污染过程耦合分析的重要因素,拓展应用景观"源汇"理论,定量解析景观格局对大气污染的源汇效应,同时进一步研发遥感反演技术,实现大气污染物分布格局的精细刻画,将为区域景观规划提供重要支撑。强化大气污染研究中的景观生态学分析途径,将有助于深化景观生态学格局与过程耦合研究体系,也将为景观可持续管理提供有力的科学支撑。     

Air pollution and its effect on health

An experimental study of the effect of air pollutants on health can be undertaken only subsequent to the creation of synthetically polluted atmosphere in exposure chambers as a readily available and easily controllable laboratory tool. The many and varied pollutants must be studied singly and in combination so as to reproduce any synergistic or antagonistic effects that may exist. A study of pollutant substances at their source is wholly inadequate in view of the pronounced photo-chemical activity in the atmosphere. The products of this activity may well be the significant ones insofar as morbid effects are concerned. In the acute and subacute biological studies, both in vitro and in vivo systems are being used with the experimental progression being from the simple to the complex.