不同棉田昆虫群落的比较研究

本文对 2种不同栽培措施 (直播棉田与覆盖棉田 ) ,4种不同施药水平 (不施药、施 1次药、施 4次药、施 6次药 )的棉田的昆虫群落的特征指数进行了分析比较。连续多次施药会降低棉田昆虫群落的丰富度、多样性和均匀度。因此 ,在棉田害虫的综合治理中 ,应当不施药或尽量少施药 ,以利于充分利用天敌的自然控制作用 ,维持棉田生态系统的稳定。     

Large-scale purification of fungal glucoamylases using anion-exchange resin chromatography

Anion-exchange chromatography on polystyrene resin is shown to be more effective than DEAE-cellulose for purification of glucoamylase from crude enzyme extracts of Aspergillus awamori or from commercial preparations. The glucoamylase from A. awamori culture medium was purified to electrophoretic homogeneity with yields approaching 80%.     

成年住院患者真菌感染的流行病学及预后因素分析

目的 了解成年住院患者真菌感染的流行病学特点及预后相关因素,为早期发现和治疗真菌感染提供依据。方法 分析2015年5月至2016年4月于浙江省人民医院进行住院治疗的真菌感染患者（共434例,年龄均大于16岁,均为院内感染,不含真菌性阴道炎）的流行病学特征,,并对影响患者预后的因素进行回顾性分析。结果 434例住院患者真菌感染病例中,病原菌主要为白假丝酵母,占78.81%,易感病区为主要呼吸内科、血液科、重症监护室,分别占21.89%、9.45%和8.76%。易感部位主要是下呼吸道,占74.66%。在真菌感染患者的预后因素分析中,性别（男）、年龄、肿瘤、呼吸衰竭、心脏疾病和免疫抑制剂方面差异均具有统计学意义（P呼吸衰竭>性别（男）>肿瘤>年龄>心脏疾病。结论 真菌感染主要由白假丝酵母引起,好发于下呼吸道;患者主要集中在呼吸内科、血液科和重症监护室等。年龄较大的男性真菌感染患者预后不及一般患者,当伴有肿瘤、呼吸衰竭、使用免疫抑制剂等预后因素时,预后会更差。因此,在治疗此类患者时,应密切监测患者情况,并及时给予抗真菌治疗,以提高患者的治愈率和存活率。     

灵芝免疫调节蛋白LZ-8的制备和晶体分析

LZ-8蛋白是从灵芝菌丝中分离到的真菌免疫调节蛋白,具有多种免疫调节功能,然而这一蛋白的作用机制尚不清楚。通过蛋白质晶体结构的解析,能够得到蛋白质空间结构特点,从而阐述蛋白质功能的机制。旨在得到LZ-8蛋白的晶体,并获得空间结构数据。以pET21a为表达载体,获得诱导表达的rLZ-8,通过亲和层析、分子筛凝胶层析和阴离子交换层析纯化,蛋白纯度在98%以上,采用悬滴气相扩散法得到蛋白晶体,并获得3.2?数据,为进一步对真菌免疫调节蛋白功能和结构的研究奠定了基础。     

Comparison of fungal communities among ten macrophyte rhizospheres

The fungal community composition, size and several physico-chemical properties were individually investigated in ten macrophyte rhizospheric substrates using nested PCR-denaturing gradient gel electrophoresis and soil chemical methods. Results indicated that both Dothideomycetes and Sordariomycetes were dominant fungi in macrophyte rhizospheric substrates, and denitrifying fungi (Fusarium graminearum) was found in nine of ten macrophyte rhizospheres. Fungal Shannon-Wiener diversity index (H) and richness (S) in Thalia dealbata, Typha latifolia, Iris hexagona and Hemerocallis aurantiaca rhizospheres were higher than those in other six rhizospheres. Fungal number and biomass were 1.91 × 10³ CFUs g^?1 dw and 1.53 μg ergosterol g^?1 dw in Iris pseudacor rhizosphere, and were greater than in other nine rhizospheres. The correlation analysis showed that fungal number and biomass significantly and positively correlated to total soil phosphorus, while fungal H and S were significantly and negatively correlated to total organic carbon. The principal components analysis (PCA) showed that the fungal community significantly divided ten macrophyte rhizospheres into four groups, showing the significant difference of fungal communities among ten rhizospheric substrates. The current study revealed for the first time the importance of rhizospheric fungal community in distinguishing macrophyte rhizospheres, thus will undoubtedly widen our insight into fungal communities in aquatic rhizospheres.     

Current updates on fungal endocarditis

Fungal endocarditis (FE) is a rare disease but in recent years its incidence as well as mortality is increasing particularly in developing nations. Candida and Aspergillus species occupy the prominent position as etiological agents of this invasive disease. Intravenous devices such as pacemakers, central line related thrombosis and prolonged use of antibiotics are major risk factors for FE. The epidemiology of endocarditis cases is also evolving over time with exceptionally rare species causing more invasive disease. Research over the last decade has also delineated the underlying pathogenic mechanism of FE. Improved understanding of these mechanisms will help to combat the increasing problem of antimicrobial drug resistance. The diagnosis of FE is dependent on the sensitivity and specificity of the method as fungi generally do not grow well in blood cultures. More advanced techniques including molecular and immunological assays now play a central role in accurate identification of causative fungal pathogens especially in culture negative scenario. In developing nations such as India, blood culture reports are generally negative due to prior antibiotic therapy. Echocardiography has emerged as the potential imaging technique for identifying invasive endocarditis including small masses of vegetation or abscess. Successful treatment often requires both the surgical interventions and prolonged antifungal therapy. In the present review, we briefly highlight the mechanisms of pathogenesis of this rare emerging disease along with the risk factors involved, the diagnostic criteria and the treatment strategy.     

肝硬化患者无菌腹水中真菌DNA的检测及易位研究

目的检测和分析肝硬化患者无菌腹水中真菌DNA存在状况。方法选取118例无菌腹水的肝硬化患者为研究对象,分别采集患者刚入院时的腹水、血液和粪便标本。应用PCR技术直接检测标本的真菌DNA并克隆测序。并收集患者临床资料,对患者临床症状及检验结果进行分析比较。结果1名患者的腹水、血液、粪便中同时检测到真菌DNA,14名患者的腹水和粪便中同时检测到真菌DNA,3名患者的血液和粪便中同时检测到真菌DNA,大部分序列间的相似性高于99％。测序检测到最多的菌种为Candidaalbicans。结论肝硬化患者无菌腹水中能够检测到真菌DNA,并且提示在肝硬化患者腹水和血清中检测到的真菌DNA易位于肠道。     

Comparative studies on amino and thiol groups in myosins from different sources.

Myosins from rabbit white and red skeletal, rabbit heart, fish skeletal and chicken gizzard muscles, as well as from human platelets were subjected to trinitrophenylation by trinitrobenzene sulfonate and alkylation by N-ethylmeleimide which affected their amino and thiol groups, respectively. The blocking of amino groups was carried out in the presence or in the absence of Mg-ADP and was followed both spectrophotometrically and enzymatically. Essential amino groups, whose modification throughly changes the enzymic characteristics of myosin, were found in heart and in all skeletal muscle myosins but were absent in myosins from chicken gizzard muscle and from human platelets. The reaction of these amino groups was highly retarded in the presence of Mg-ADP. Alkylation of thiols led to loss of the K+-activated ATPase (ATP phosphohydrolase, EC 3.6.1.3) in all myosins. However, the rate of loss of activity varied from one myosin to another and, for a given myosin, was affected by the presence of nucleotides and by the value of the ionic strength. The change in Ca(2+)-activated ATPase activity (ATP phosphohydrolase, EC 3.6.1.3) on alkylation was influenced by the presence of Mg - ADP during the reaction. In the absence of this nucleotide, the Ca(2+)-ATPase activity increased and reached a plateau as a consequence of modification. The extent of activation largely depended on the origin of the myosin. When alkylation was carried out in the presence of Mg-ADP, the Ca(2+)-ATPase activity as a function of time exhibited a maximum but the descending part of the curve was absent in myosins from heart and gizzard muscles.     

Comparative phylogeography, genetic differentiation and contrasting reproductive modes in three fungal symbionts of a multipartite bark beetle symbiosis

Multipartite symbioses are complex symbiotic relationships involving multiple interacting partners. These types of partnerships provide excellent opportunities in which to apply a comparative approach to identify common historical patterns of population differentiation and species-specific life history traits. Using three symbiotic blue-stain fungal species (Ophiostomatacea) associated with outbreaking populations of the mountain pine beetle (Dendroctonus ponderosae Hopkins) in western Canada, we applied phylogenetic, population genetic and demographic approaches to clarify phylogeographic patterns among the three fungal species. Broadly, the three species showed significant population differentiation, forming northern and southern populations, despite dramatic differences in haplotype diversity. Finer structuring and population demographic patterns were less consistent, showing some interspecific incongruence. By contrasting these species simultaneously, we were able to identify differences in recombination rate and ecological traits that can explain the observed patterns of incongruence among the fungal species. By applying a comparative approach to partners of a multipartite symbiosis, we were able to distinguish congruent population structuring and species-specific differences that help us to understand the complexity and evolution of this symbiotic system.     

Detection of fungal spores from contaminated surfaces by the polymerase chain reaction

A method has been developed to detect fungal spores in dust samples collected from internal surfaces of air-conditioning ducts. The method is based on the utilization of the polymerase chain reaction (PCR) with specific primers for fungal species. PCR amplification is carried out directly in boiled samples avoiding time-consuming DNA preparation steps. The presence of bovine serum albumin in the reaction mixture overcame the inhibitory effect of the humic acids present in the dust.     

Comparative study of biochemical properties of glucoamylases from the filamentous fungi Penicillium and Aspergillus

Here we report the first isolation to homogeneous forms of two glucoamylases from the fungus Penicillium verruculosum and their study in comparison with known glucoamylases from Aspergillus awamori and Aspergillus niger. Genes that encode glucoamylases from P. verruculosum were cloned and expressed in the fungus Penicillium canescens, and the recombinant glucoamylases were obtained with subsequent study of their molecular weights, isoelectric points, optimal temperature and pH values, and stability. The catalytic activities of the recombinant glucoamylases were determined in relation to soluble potato starch. Changes in molecular mass distribution and content of low molecular weight products during starch hydrolysis by glucoamylases from P. verruculosum, A. awamori, and A. niger were studied. An exo-depolymerization mechanism was established to be the pathway for destruction of starch by the glucoamylases.     

鹌鹑、果蝇遗传实验价值的比较研究

果蝇是生物学科遗传实验的经典材料,鹌鹑是新近开发的实验动物。对两者的实验价值进行比较研究结果表明：果蝇具有生活史短、繁殖率高、性状突出,在教学实验中还表现出知识性强,实验面宽等特点;鹌鹑具有直观性强、时代间隔短、繁殖率高、贴近生活、服务生产、供人观赏、饲养简便、遗传性状突出、知识性强等特点。同时,两者也都有不足。通过比较研究为合理安排生物实验课,进行校本实验开发提供科学依据。     

New insights into the fungal community from the raw genomic sequence data of fig wasp Ceratosolen solmsi

Background

To date, biologists have discovered a large amount of valuable information from assembled genomes, but the abundant microbial data that is hidden in the raw genomic sequence data of plants and animals is usually ignored. In this study, the richness and composition of fungal community were determined in the raw genomic sequence data of Ceratosolen solmsi (RGSD-CS).

Results

To avoid the interference from sequences of C. solmsi, the unmapped raw data (about 17.1%) was obtained by excluding the assembled genome of C. solmsi from RGSD-CS. Comparing two fungal reference datasets, internal transcribed spacer (ITS) and large ribosomal subunit (LSU) of rRNA, the ITS dataset discovered a more diverse fungal community and was therefore selected as the reference dataset for evaluating the fungal community based on the unmapped raw data. The threshold of 95% sequence identity revealed many more matched fungal reads and fungal richness in the unmapped raw data than those by identities above 95%. Based on the threshold of 95% sequence identity, the fungal community of RGSD-CS was primarily composed of Saccharomycetes (88.4%) and two other classes (Agaricomycetes and Sordariomycetes, 8.3% in total). Compared with the fungal community of other reported fig wasps, Agaricomycetes and Eurotiomycetes were found to be unique to C. solmsi. In addition, the ratio of total fungal reads to RGSD-CS was estimated to be at least 4.8 × 10⁻³, which indicated that a large amount of fungal data was contained in RGSD-CS. However, rarefaction measure indicated that a deeper sequencing coverage with RGSD-CS was required to discover the entire fungal community of C. solmsi.

Conclusion

This study investigated the richness and composition of fungal community in RGSD-CS and provided new insights into the efficient study of microbial diversity using raw genomic sequence data.

Electronic supplementary material

The online version of this article (doi:10.1186/s12866-015-0370-3) contains supplementary material, which is available to authorized users.     

真菌来源的药用天然产物

天然产物及其衍生物,包括基于天然产物药效基团结构设计的化合物,约占临床药物的50%以上。几个世纪以来,真菌天然产物的药用价值闻名于世。无论从市场前景还是人道主义角度,真菌来源的小分子药物都具有极高的应用价值。本篇综述总结了真菌天然产物在临床上的应用,并以他汀类药物的研发历程揭示了真菌来源小分子是化学合成药物研发的重要灵感源泉。本篇综述涵盖了真菌来源的药物小分子,包括天然药物、相关衍生物以及结构修饰药物。     

Comparative studies on the effects of anions on ATPase and acid phosphatase activities from different sources

The effect of several anions on Mg²⁺-ATPase activity [EC 3.6.1.3 [EC] ]was studied in crude extracts of the following sources: twelvespecies of bacteria, one fungus, one yeast, six species of algae,five higher plant tissues, and two animal tissues. All the materialsexamined exhibited Mg²⁺-ATPase activity at pH 7.5. Except fora few species of bacteria, blue-green alga and etiolated seedlingsof a leguminous plant, Mg²⁺-ATPases of all the materials studiedwere stimulated two- to ten-fold by the addition of Group VIanions such as sulfite, selenite, and chromate. This stimulationseems to be a common characteristic of ATPases of most bacteria,chloroplasts, and mitochondria. On the other hand, the stimulation of acid phosphatase by sulfatewas not observed in any organism other than Thiobacillus thiooxidans. (Received July 27, 1977; )     

Delving into the dark ecology: A continent-wide assessment of patterns of composition in soil fungal communities from Australian tussock grasslands

Soil fungi play essential roles in many terrestrial processes, but our knowledge of the forces governing fungal distribution and community composition along broad-scale environmental gradients is still limited. In this study, we explored biogeographic distribution and composition of soil fungal communities associated with 62 tussock grasslands across different regions of Australia. Climatic parameters had only a limited correlation with fungal community structure, while edaphic variables and spatial distance were significantly associated with changes in fungal community composition. We also observed high variations in composition among fungal assemblages from different ecological regions, suggesting some regional endemism in these communities. The discrete distribution of fungi in soil was further confirmed by indicator analysis, which identified distinct indicator operational taxonomic units associated with grasslands from different climatic regions. Finally, fungi with flexible trophic interactions had a central role in the network architecture of both arid and temperate communities. Taken together, the results from our study confirm the prominent role of soil physico-chemical status and geographic location in determining fungal biogeographic patterns over large scales in Australia.     

国产胡桃科次生木质部导管分子的比较解剖及其系统位置的讨论

通过对国产胡桃科6属13种植物所做的次生木质部导管分子的长度,弦径,端壁斜度,穿孔板类型,管孔形状及其排列,导管密度及其在分类中作用的解剖学研究,证实了从导管分子来看黄杞属和青钱柳属是相当原始的属,而化香树属,山核桃属是最进化的属,并根据导管分子的解剖学特征探讨了胡桃科各属间的进化顺序。     

Physical properties of fungal chitosan

Fungi are promising alternative sources of chitosan. This study evaluated the physical properties of fungal chitosan from Absidia coerulea (AF 93105), Mucor rouxii (Ag 92033), and Rhizopus oryzae (Ag 92033). FT-IR and X-ray diffraction of the extracted products showed typical chitosan peak distributions which confirmed the extracted products to be chitosan. All of their glucosamine contents and degrees of deacetylation (DD) were over 80%, not showing obvious differences respectively. However, differences had been observed in their molecular weight (M_w), ranging from 6.6  to 560 kDa. The results of this study demonstrated that different fungi could produce different M_w chitosan with high DD and high purity.