Role of Protein in Fungal Biomineralization of Copper Carbonate Nanoparticles

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一组厌氧真菌菌系产阿魏酸酯酶的初步研究

利用玉米秸秆粉为唯一碳源的筛选培养基,从肉牛瘤胃液中筛选构建了一组厌氧真菌菌系,研究了该菌系产阿魏酸酯酶的特征.阿魏酸酯酶的最适pH为8.0,最适温度为40℃,最高酶活力为19.1 mU/mL,在pH 6.0 ～8.0及35～45℃之间,酶活性保持相对稳定.Mg2+对酶活力具有激活作用,Fe2、Cu2+、Fe3+等均抑制酶活力.     

A Comparative Study of Caffeine Degradation by Four Different Fungi

The objective of the present study is to investigate the caffeine-degrading abilities of different fungi and to apply this knowledge to environmental remediation and industrial decaffeination process. Chrysosporium keratinophilum, Gliocladium roseum, Fusarium solani, and Aspergillus restrictus were isolated from the coffee pulp obtained from a coffee estate. Pure cultures of fungi were isolated on standard conventional potato dextrose broth (PDB) medium and authenticated. Pure cultures were subjected to a caffeine tolerance study at different concentrations of caffeine (1–8 g/L) in potato dextrose agar (PDA) and minimal media. On PDA, Fusarium solani could tolerate caffeine concentration up to 8 g/L, whereas Chrysosporium keratinophilum, Gliocladium roseum, and Aspergillus restrictus could tolerate up to 6 g/L. On minimal agar medium containing different concentrations of caffeine (1–8 g/L), Fusarium solani tolerated up to 8 g/L and the other fungi up to 2 g/L. A time-bound caffeine degradation study was undertaken at 1 g/L concentration of caffeine and glucose in nitrogen-containing and nitrogen-free liquid minimal media by subjecting the four fungi to shake flask culture at 120 rpm and 30°C. Degradation of caffeine up to 7 days at 24-h intervals was analyzed by high-performance liquid chromatography (HPLC). Gliocladium roseum followed by Aspergillus restrictus showed maximum degradation of caffeine at 0.47 and 0.3 mg/ml, respectively, by 96 h in nitrogen-containing minimal medium, whereas Fusarium solani showed maximum degradation of caffeine by 48 h (0.35 mg/ml) and Chrysosporium keratinophilum by 72 h (0.29 g/ml). In nitrogen-free minimal medium, Chrysosporium keratinophilum showed maximum degradation of caffeine at 72 h (0.45 mg/ml), followed by Gliocladium roseum, Fusarium solani (0.3 mg/ml), and Aspergillus restrictus (0.25 mg/ml) at 96 h. Overall, Chrysosporium keratinophilum showed a comparatively higher rate of caffeine degradation in minimal medium with or without a nitrogen source as compared with the other three fungi, indicating that nitrogen affects caffeine metabolism.     

1型糖尿病患者骨密度的变化及相关因素分析

目的：观察1 型糖尿病患者骨密度（bone mineral density,BMD）的变化及其影响因素。方法：采用双能X 线骨密度仪测定108 例1 型糖尿病患者及106 例非糖尿病人群腰椎1 至4（L1、L2、L3、L4、、L1-4 总体）及左侧髋部（股骨颈、大转子、ward＇s 三角、股骨干及左髋总体）骨密度,同时测定受试者年龄、身高、体重、腰围、臀围,1 型糖尿病患者病程、糖化血红蛋白（HbA1c）等指标,利用多元回归分析1型糖尿病患者骨密度的相关因素。结果：L1-4 总体BMD 和左髋总体BMD 与年龄、HbA1c 呈负相关,与BMI呈正相关（P〈0.05）;左髋总体BMD 与性别有关（P〈0.05）。结论：1型糖尿病患者BMD 低于对照人群,1型糖尿病患者的性别、年龄、BMI、HbA1c 水平与BMD 关系密切。     

Effects of Mineral Structure and Microenvironment on K Release from Potassium Aluminosilicate Minerals by Cenococcum geophilum fr

K-bearing minerals with enormous reserve in the world, were not easy to provide the available K nutrient element for plant direct uptake because of the slow K release rate. With the potential potassium-solubilizing microorganisms, the slow K release rate from minerals would be improved significantly. In this work, Cenococcum geophilum Fr, one of the most common ectomycorrhizal fungi in boreal to temperate regions, was adopted to dissolve K-bearing minerals for K release. Five kinds of potassium aluminosilicate minerals were tested by bioleaching experiments in pure culture, including feldspar, nepheline, biotite, muscovite and illite. The available and unavailable potassium amounts in minerals before and after bioleaching were measured and compared with each other. The effect of mineral structure on the potassium solubilization efficiency by Cenococcum geophilum Fr. was discussed. Furthermore, the microenvironment formation between fungi and mineral surface to enhance the K release rate was investigated through detecting K, Al, Si concentrations and metabolites amounts (polysaccharide and organic acids) in microenvironment and external environment, respectively. Experimental results demonstrated that Cenococcum geophilum Fr. was a potential candidate of potassium solubilizing microorganisms, and both mineral structure and microenvironment have significant effects on the K release rate.     

The Degradation of Dimethoate and the Mineral Immobilizing Function for Cd2+ by Pseudomonas putida

Organophosphorus pollution and heavy metal pollution are prominent in China and have caused increasingly severe environmental pollution. This research used Pseudomonas putida to degrade dimethoate so as to induce the formation of calcium carbonate (CaCO₃) and calcium phosphate (Ca₃(PO₄)₂) in beef extract peptone medium. In addition, the mineral immobilizing function of the generated Ca₃(PO₄)₂ and CaCO₃ for Cd²⁺ was studied by adding different concentrations of Cd²⁺ to the culture solution. Meanwhile, transmission electron microscopy (TEM), scanning electronic microscopy (SEM), X-ray diffraction, gas chromatography and atomic absorption spectrophotometry were used to investigate the biodegradation of dimethoate, the concentration variation of Ca²⁺ and Cd²⁺, the mineral and chemical compositions of the precipitates. The results showed that the growth of P. Putida could increase the pH value of the culture solution and effectively degrade the organophosphorus pesticide dimethoate. Besides, the concentration of Ca²⁺ in the culture solution decreased significantly in the first four days and then tended to be stable. Moreover, the TEM and SEM results presented that there were large amounts of biogenic sedimentary CaCO₃ and a little Ca₃(PO₄)₂ in the precipitates. Furthermore, in the employed culture system, the removal rates of Cd²⁺, when added at two different concentrations (6 ppm and 15 ppm), reached 100%. Therefore, this study provided a new idea for treating wastewater polluted with organophosphorus pesticide and heavy metals by using microorganisms.     

Effects of Species Diversity on Establishment and Coexistence: A Phylloplane Fungal Community Model System

A model system was devised, evaluating the influence that species diversity (species richness) has on fungal establishment and coexistence. Seven members of the fungal phylloplane community of Vaccinium macrocarpon (American cranberry) were selected to assess how species diversity affected development and coexistence of another community member, Pestalotia vaccinii. Pestalotia was engaged in competitive interactions on 1% Malt Extract Agar (MEA) petri dishes with each of the seven individual saprotrophs (two-way interaction), in random combinations with three of the seven saprotrophs (four-way interaction), and in random combinations with five of the seven saprotrophs (six-way interaction). The saprotrophic fungi used in this study were Aspergillus sp., Alternaria alternata, Cladosporium cladosporoides, Curvularia lunata, Epicoccum purpuracens, Penicillium sp., and Pithomyces chartarum. We hypothesized that species diversity would have a significant impact on the establishment and coexistence of Pestalotia vaccinii in culture. In an effort to minimize density-dependent effects, the number of viable spores employed in the three types of interactions was kept constant. Target spore concentrations of 50 viable spores of P. vaccinii and 50 saprotroph spores were used, regardless of the number of species involved in the interaction. This proved to be a very important factor in the experiment. As our results show, species diversity had little or no effect on the establishment and coexistence of Pestalotia vaccinii; however, spore density played an extremely important role in the establishment and development of fungal propagules in our model.     

1株甲苯降解真菌的筛选鉴定及其降解甲苯的特性

从实验室保存的7株真菌筛选到1株能高效降解甲苯的菌株H1,基于形态特征、ITS序列系统学分析,将H1菌株鉴定为毛栓菌（Trametes hirsuta）。利用正交设计实验方法研究了温度、pH值、甲苯浓度和吐温80浓度对H1菌株降解甲苯的影响,研究得出该菌株降解甲苯的最适条件为30℃、pH 5.0、甲苯浓度300mg/L、吐温80浓度0.05%,在该条件下H1对甲苯的最大降解率为85.3%,降解率比未优化之前有了显著提高。比较了H1菌株在3种培养基产生漆酶的能力,H1在土豆葡萄糖培养基产酶能力最强,在第7天达到酶活高峰16 500 U/L。H1在甲苯为唯一碳源的培养基中,漆酶酶活最低,培养7 d时漆酶酶活为589 U/L。     

白腐真菌对染料废水脱色及降解的研究

染料废水是最难处理的工业废水之一,近年来许多学者就白腐真菌对染料废水的脱色进行了广泛的研究,系统介绍了白腐真菌对染料脱色和降解作用的研究进展,脱色机理及其影响因素,旨在为以后真菌对染料废水的脱色及降解提供参考和依据。     

股骨近端三维有限元模型评价髋部骨折患者骨密度

目的：探究骨密度与老年髋部骨折股骨近端三维有限元模型密度的关系。方法：选取8 例老年髋部骨折,其中4 例股骨颈骨 折,4 例股骨转子间骨折;左侧肢体3 例,右侧肢体5 例。分别测定腰椎骨密度和双侧髋关节CT 资料,运用Mimics软件和abaqus 软件对健侧股骨近端进行重建和计算出该模型的密度。结果：股骨转子间骨折组腰椎骨密度为(-4.05± 0.24) g/cm2,三维有限元模 型密度为[(1.15± 0.02)× 106],均低于股骨颈骨折组的(-3.15± 0.54) g/cm2,[(1.34± 0.06)× 106],两组比较差异均有统计学意义（均 P<0.05）。腰椎的骨密度与三维有限元模型密度成线性正相关（r=0.881,P=0.004）。结论：骨密度与老年髋部骨折股骨近端三维有限 元模型密度成线性正相关的关系,可为进一步用有限元分析法探讨老年髋部骨折部位与骨密度的关系提供理论依据。     

Fungal degradation of lantadene A, the pentacyclic triterpenoid hepatotoxin of lantana plant

Seven white-rot fungi, known to degrade complex biomolecules and xenobiotics were used for investigation on biodegradation of lantadene A (LA), the bioactive pentacyclic triterpenoid of Lantana camara. Pleurotus sajor-caju and Merulius tremellosus PRL-2845 did not degrade LA. Trametes versicolor MTCC-138, Heterobasidion annosum MTCC-146, Phellinus pini RAB-83-19, Pleurotus ostreatus MTCC-142 and Phlebia radiata 2 utilized LA to the extent of 11–15.7%. This is the first report on the fungal degradation of a pentacyclic triterpenoid.     

Motif-Independent Prediction of a Secondary Metabolism Gene Cluster Using Comparative Genomics: Application to Sequenced Genomes of Aspergillus and Ten Other Filamentous Fungal Species

Despite their biological importance, a significant number of genes for secondary metabolite biosynthesis (SMB) remain undetected due largely to the fact that they are highly diverse and are not expressed under a variety of cultivation conditions. Several software tools including SMURF and antiSMASH have been developed to predict fungal SMB gene clusters by finding core genes encoding polyketide synthase, nonribosomal peptide synthetase and dimethylallyltryptophan synthase as well as several others typically present in the cluster. In this work, we have devised a novel comparative genomics method to identify SMB gene clusters that is independent of motif information of the known SMB genes. The method detects SMB gene clusters by searching for a similar order of genes and their presence in nonsyntenic blocks. With this method, we were able to identify many known SMB gene clusters with the core genes in the genomic sequences of 10 filamentous fungi. Furthermore, we have also detected SMB gene clusters without core genes, including the kojic acid biosynthesis gene cluster of Aspergillus oryzae. By varying the detection parameters of the method, a significant difference in the sequence characteristics was detected between the genes residing inside the clusters and those outside the clusters.     

石蜡油对离子注入动物细胞真空环境的保护效应初探

利用石蜡油的高效护水功能进行动物细胞(HeLa细胞)的真空及注入保护,研究了不同的预处理时间对细胞活性的影响,并将石蜡油浸泡细胞2 m in~6 m in选为最佳保护时间。当细胞经过2 m in~6 m in的预处理后再进行真空、注入,结果显示成活率大幅度提高。     

A comparison of nine species of arbuscular mycorrhizal fungi on the development and nutrition of micropropagated Rubus idaeus L. cv. Glen Prosen (Red Raspberry)

Growth, development and nutrient status of micropropagated Rubus idaeus cv. Glen Prosen in response to inoculation with nine species of arbuscular mycorrhizal (AM) fungi from three different genera was investigated. The nine species of AM fungi included, Glomus clarum, G. etunicatum, G. intraradices, Gigaspora rosea, Gi. gigantea, Gi. margarita, Scutellospora calospora, S. heterogama and S. persica. Plant responses to AM fungi varied from growth enhancement to growth depression. Depressive growth effects were specific to Gigaspora species. Furthermore, particular species of AM fungi had unique effects on the mineral status of the raspberry plants. Importance of isolate selection for inoculation of micropropagated raspberry plants is discussed. This revised version was published online in June 2006 with corrections to the Cover Date.     

Endophytic Fungal Assemblages from Inner Bark and Twig of Terminalia arjuna W. & A. (Combretaceae)

Summary Fungal endophytes reside in healthy tissues of all terrestrial plant taxa studied to date and are diverse and abundant in tropical woody angiosperms. Endophytic fungi were isolated from Terminalia arjuna, an important ethno pharmacological plant extensively used in ayurvedic medicines to treat heart ailments. Isolations were made from symptomless fresh inner bark as well as twig samples of five plants collected from three locations of riparian vegetation during two seasons (monsoon and winter) of 2003 and 2004. Two hundred and seventy eight isolates, representing 22 genera, were obtained from both seasons. Monsoon seasonal isolations representing 22 genera showed greater diversity. Coelomycetes were more numerous during the winter season than hyphomycetes and ascomycetes. Among the endophytes, the genus Pestalotiopsis dominated the endophyte assemblage of T. arjuna collected from different locations, dominance was greater during the winter season than the monsoon season. Endophytic colonization frequency was greater in inner bark (18.5%) than twigs (4.6%). The genera Pestalotiopsis (54.5%), Chaetomium (10.5%) and Myrothecium (9%) were the most predominant endophytes. Rarefaction indices indicated the highest expected number of species for bark samples, monsoon isolations and location 1 (Mysore).     

Fungal associations of Danish Calluna vulgaris roots with special reference to ericoid mycorrhiza

Fungi were isolated from young, serial-washed roots of Calluna sampled from a Danish heathland, Hjelm Hede. Of the 626 isolates, those that were dark, sterile and septate were divided into 13 morphological groups based on their appearance in culture on malt agar. Mycorrhizal synthesis in vitro showed that several groups formed typical ericoid mycorrhiza with seedlings of Calluna; these ericoid mycorrhizal fungi were morphologically similar to Hymenoscyphus ericae. The identities of the other dark, septate fungi are uncertain. Oidiodendron spp. were isolated in a very low frequency; these fungi also formed typical ericoid mycorrhiza. The Calluna root system on Hjelm Hede demonstrated a high morphological diversity among the associated dark, septate fungi suggesting that more than one fungus could coexist in the same host root system.     

阿仑膦酸钠联合阿法骨化醇对预防全髋关节置换术后患者骨矿物质流失的疗效

目的：探讨初次行全髋关节置换术后使用阿仑膦酸钠单一用药或阿仑膦酸钠与阿法骨化醇联合用药对患者假体周围骨矿物 质流失的疗效。方法：将60 名患者按照随机数字表法分为阿仑膦酸钠单一药物治疗组（n=18）、阿仑膦酸钠和阿法骨化醇联合治 疗组（n=20）和无药物治疗组（n=22）。术后1、12、24 和48 周,对患者假体周围骨矿物质密度（BMD）和生化标志物进行检测,比较 检测区域测量值的变化。结果：单个测量周期中,单一药物治疗组和联合药物治疗组在股骨矩区域的BMD 均高于无药物治疗组 （P＜0.01）。单一药物治疗组和联合药物治疗组尿Ⅰ型胶原N端肽的血浆浓度与骨碱性磷酸酶浓度显著低于无药物治疗组（P＜ 0.01）。结论：单一药物治疗和联合治疗能显著预防假体周围的骨矿物质流失,尤其对预防股骨矩位置的骨矿物质流失效果显著。     

一类嗜角蛋白真菌——金孢属的应用价值评介

金孢属(Chrysosporium)真菌在地球上分布广泛,具有较强的环境适应能力,能产生许多有用的代谢物。它们是一个喜角蛋白的类群,大多数可以产生角蛋白酶。此类真菌在国民经济中有广泛的应用价值。文中评述了金孢属真菌产生的抗癌、抗真菌、抗寄生虫等抗生素类物质的研究进展,以及此类真菌在生物防治、食品工业、日用化工、皮革生产、纺织工业、造纸工业、功能酶的生产、环境检测与保护等方面的研究状况及其潜在的应用价值和研究意义,同时介绍了金孢属的某些种作为人或动物病原菌的研究进展。     

Hormonal Control of the Shoot-to-Root Ratio Is Not Related to Water Deficiency in Wheat Plants under Mineral Deficiency

We measured the content of hormones, the rate of growth, and some parameters of water regime (water content, transpiration, and stomatal and hydraulic conductivities) one and two days after wheat plant transfer from 10 to 1% Hoagland-Arnon nutrient medium. It was shown that, a day after dilution of nutrient solution, the content of various cytokinin forms decreased in the xylem sap, shoots, and roots. This decrease was most pronounced in the case of zeatin in the xylem sap and zeatin riboside in the mature zone of the first leaf. ABA was found to accumulate in shoots. A day after dilution of nutrient solution, we observed root elongation evidently induced by mineral nutrient deficiency, and this accelerated root growth was maintained later. Two days after dilution of nutrient solution, we observed the slowing of shoot weight accumulation, whereas root weight remained unchanged. Plant growth response could be related to ABA accumulation in shoots and cytokinin depletion in the whole plant. A reduced hydraulic conductivity and water content in the growing leaf zone was detected only two days after dilution of nutrient solution. Thus, changes in the growth rates and hormone contents could not result from disturbances in water regime induced by mineral nutrient deficiency.     

棘豆蠕孢菌多糖抗氧化活性研究

以总还原力、羟自由基(.OH)抑制活性、超氧阴离子自由基O 2的清除率、亚硝酸根离子(NO2-)的清除率为评价指标,探明内生真菌棘豆蠕孢菌(Embellisia oxytropis Q.Wang,Nagao&Kakish)次级代谢产物多糖的抗氧化作用。结果表明:棘豆蠕孢菌多糖的抗氧化活性随着多糖浓度的增加而增大,呈量效关系,其中胞内多糖对自由基和亚硝酸根离子具有较好的清除作用,清除率高达80%以上,与维生素C对照组接近。