淡紫紫孢菌亲环蛋白PlCYP6互作蛋白的筛选

以淡紫紫孢菌中参与盐胁迫响应的亲环蛋白PlCYP6为研究对象,采用免疫沉淀联合质谱分析及酵母双杂交等技术筛选淡紫紫孢菌中与PlCYP6互作的蛋白.结果显示,受PlCYP6特异钓取的482个蛋白的功能主要涉及细胞代谢.其中,乙醇脱氢酶1(alcohol dehydrogenase I,ADH1)与PlCYP6直接互作,且...     

小麦-禾谷镰孢菌互作机制的研究进展

禾谷镰孢菌(俗称禾谷镰刀菌,Fusarium graminearum)引起的小麦赤霉病是小麦生产上一种极具毁灭性的真菌病害,在世界各主要产麦国普遍发生,我国是世界上受害面积最大的国家,该病害严重威胁我国粮食生产和食品安全.解析小麦-禾谷镰孢菌之间的互作机制,挖掘有效抗病基因,对于解决小麦赤霉病这一世界难题具有重要意义....     

束状刺盘孢的体外培养条件研究

目的对束状刺盘孢体外培养,观察形态特征。方法将束状刺盘孢接种在马铃薯葡萄糖琼脂培养基(PDA)中分别置于4℃、28℃、35℃和37℃下培养2周,观察生长情况;选取生长最好的菌株分别接种在沙堡弱培养基(SDA)、PDA、察氏培养基(CPA)、胡萝卜琼脂培养基(CDA)和玉米粉培养基(CMA)中,同一温度下培养2周,观察菌落形态及镜下形态。结果菌株在28℃条件下生长最快、菌落发育饱满、产生灰色色素;菌株在五种培养基中生长快慢依次是PDA>CDA>CMA>SDA>CPA,菌落在PDA、CDA和CMA中呈鼠灰色,SDA中呈白色和棕色,CPA中呈白色和鼠灰色,SDA和CPA中未见分生孢子和刚毛产生。结论在PDA、CDA和CMA中28℃条件下,较适合束状刺盘孢生长。     

苹果链格孢菌与寄主叶片互作的超微结构研究

以苹果杂交组合(‘华脆’ב金冠’)F1代杂种实生苗群体易感病株系为材料,通过扫描电镜、透射电镜等观察方法,对苹果链格孢菌与寄主叶片互作过程进行了细胞学观察,分析苹果链格孢菌侵染寄主的动态过程和变化规律,以揭示苹果病害发生机制。结果表明,苹果链格孢菌侵染寄主叶片时,多数在表皮分枝扩展,很少通过气孔器或其他方式入侵细胞内部。互作后期,寄主叶细胞内叶绿体和质膜变化显著,多数细胞器降解,表明病原菌已分泌AM毒素作用于寄主。     

禾谷镰孢菌β2微管蛋白与苯并咪唑类杀菌剂互作研究

小麦赤霉病是小麦上的主要病害之一,在全世界范围内引起该病害的致病菌主要是禾谷镰孢菌Fusarium graminearum。目前,使用杀菌剂是生产上防治小麦赤霉病发生和危害的主要手段,常用的杀菌剂主要有苯并咪唑类杀菌剂(benzimidazoles)等,苯并咪唑类杀菌剂的作用靶标是β2微管蛋白。本研究旨在探究小麦赤霉病菌中β2微管蛋白与苯并咪唑类杀菌剂的互作机制,通过同源建模的方法获得了禾谷镰孢菌β2微管蛋白的三维结构,并在此基础上将β2微管蛋白与4种苯并咪唑类杀菌剂(多菌灵、苯菌灵、噻菌灵、甲基硫菌灵)进行分子对接。分子对接结果显示β2微管蛋白第198位苯丙氨酸和第236位缬氨酸与4种苯并咪唑类杀菌剂直接互作形成氢键,第50、134、165、167、198、200、236、237、239、240、250、253、257、314位氨基酸形成药剂结合口袋。通过比较β2微管蛋白与4种苯并咪唑类杀菌剂结合自由能,发现与其他3种杀菌剂相比,β2微管蛋白与多菌灵的结合自由能最小(-5.72 kcal/mol),说明其与多菌灵互作亲和力更强。采用菌丝生长速率法测定了禾谷镰孢菌对4种苯并咪唑类杀菌剂的EC₅₀值,禾谷镰孢菌对多菌灵、苯菌灵、噻菌灵、甲基硫菌灵的EC₅₀值分别为0.772、0.862、1.088、13.266 mg/L,该结果表明禾谷镰孢菌对多菌灵的敏感性强于其他3种杀菌剂,与分子对接结果相吻合。     

基于共表达网络和蛋白互作分析挖掘小麦赤霉病抗性相关核心蛋白

高通量蛋白组学技术能够鉴定小麦特定组织的蛋白表达水平,对小麦穗轴混池蛋白组学分析得到的632个差异表达蛋白数据进行共表达网络分析,同时筛选显著表达模块进行蛋白质互作分析,以期挖掘出与小麦赤霉病抗性相关的蛋白。WGCNA分析结果共构建了12个表达模块,其中模块6与赤霉病抗病呈极显著相关,模块8显著相关。蛋白互作网络分析筛选到7个候选蛋白,分别为参与毒素降解的GST （glutathione S?transferase）和AdoMet?MTase（S?adenosylmethionine?dependent methyltransferase）,参与光合作用的IM30（membrane?associated 30 Da, chloroplastic）、PnsL2（photosynthetic NDH subcomplex L 2）和PPL1（PsbP?like protein 1）,以及抗逆相关的UCHL（ubiquitin carboxyl?terminal hydrolase）和MetAP2（methionine aminopeptidase 2）。这些蛋白可能在赤霉病抗、感病响应中具有重要作用,值得进一步研究。     

西瓜炭疽病菌圆刺盘孢分生孢子产生条件的研究

为研究圆刺盘孢Colletotrichum orbiculare的分生孢子产生条件,通过改变培养基的成分、理化性状及培养条件等方法,进行了诱导产孢试验,并对所产生的分生孢子量进行测定。结果表明,C.orbiculare在西瓜茎叶煎汁培养基上25℃恒温黑暗培养30d可产生大量分生孢子,产孢量高达7.15×109个/m L。在显微镜下观察发现,病菌在西瓜茎叶煎汁培养基上和在西瓜茎秆病斑上产生的分生孢子在形态上存在差异,前者产生的分生孢子稍短和略宽,两端钝圆;而后者产生的分生孢子相对长而细,两端较尖。试验证明寄主西瓜茎叶成分对病菌分生孢子的产生具有明显促进作用。     

刺盘孢属及其近似属的五个中国新记录种

报道我国5个新记录种:榕刺盘孢 Colletotrichum ficus Koord.、印度胶树刺盘孢Colletotrichum fici-elasticae、卫矛痂圆孢Sphaceloma euonymi-jasponici、茼蒿柱盘孢Cylindrosporium chryanthemi和楤木Gloeosporium araliae.研究标本保存于云南农业大学真菌标本室(MHYAU)和西北农林科技大学真菌标本室(FHNWAC).     

束状刺盘孢角膜炎的实验研究

目的初步研究束状刺盘孢感染兔角膜的临床表现和组织病理学特征。方法选择15只新西兰白兔,应用基质内直接注射法建立模型。肉眼观察角膜变化,并在接种后第5 d、14 d、21 d处死家兔,对角膜行HE染色和PAS染色,观察其组织病理学改变。结果兔束状刺盘孢角膜炎动物模型成功建立,肉眼可以见到典型的真菌性角膜炎的表现。组织病理学检查,在感染早期即可看到大量真菌病原体生长,菌丝垂直于角膜基质,后期出现新生血管和瘢痕。结论角膜基质内直接注射法复制真菌性角膜炎动物模型成功率高、稳定。兔束状刺盘孢角膜炎有典型的真菌性角膜炎的表现,组织学中菌丝垂直于角膜基质生长。     

生物信息学分析人类病毒互作广谱蛋白的特征

了解病毒与人类蛋白的相互作用对于理解病毒感染宿主机制非常重要,已有研究主要集中在病毒如何进入宿主细胞、复制、扩散和致病等方向上,对病毒与人类蛋白的相互作用模式缺乏系统研究。本研究中我们构建了迄今为止最全面的病毒与人类之间的蛋白相互作用网络,涵盖来自218种病毒的1 674种蛋白与来自人类的13 724种蛋白的108 832对蛋白相互作用;在此基础上鉴定出109个至少与12种病毒家族存在蛋白相互作用的人类蛋白,定义为人类的病毒互作广谱蛋白（简称广谱蛋白）;从结构、功能、蛋白互作网络以及组织表达量等四个方面系统地分析了广谱蛋白的特征,发现广谱蛋白相较于非广谱蛋白以及其它人类蛋白具有更密集的转角结构、更多的结构域、更高的网络中心度和组织表达量,表明它们可能在病毒感染宿主过程中起着重要作用。本研究有助于加深我们对于病毒感染人类模式的理解,同时也对进一步探究病毒与疾病之间的关联有一定的帮助。     

Detection of latent infections caused by Colletotrichum sp. in olive fruit

Aims

To set up a practical method to detect latent infections of Colletotrichum sp., the causal agent of olive anthracnose, on olives before the onset of disease symptoms.

Methods and Results

Freezing, sodium hydroxide (NaOH), ethanol and ethylene treatments were evaluated to detect latent infections on inoculated and naturally infected olive fruit by Colletotrichum sp. as non‐hazardous alternatives to paraquat. Treatments were conducted using fruit of cultivars Arbequina and Hojiblanca. The disease incidence and T₅₀ were calculated. Dipping in NaOH 0·05% solution and the paraquat method were the most effective treatments on both inoculated and naturally infected fruit, although the value of T₅₀ was lower for the NaOH method than for the paraquat method in one of the experiments. Subsequently, the dipping time in NaOH 0·05% was evaluated. Longer dipping times in NaOH 0·05% were better than shorter ones in cultivar Arbequina, with 72 h being the most effective in cultivar Hojiblanca.

Conclusions

NaOH solution is a practical method to detect latent infections of Colletotrichum sp. on immature olive fruit.

Significance and Impact of the Study

This study is relevant because we set up a viable, non‐hazardous alternative to paraquat to detect latent infections of Colletotrichum sp. using NaOH. The use of NaOH is a simple and eco‐friendly tool that allows the determination of the level of latent infections by Colletotrichum in olives. Therefore, our method will be useful in decision‐making processes for disease management before the appearance of the first visible symptoms.     

In vitro screening of biological and chemical agents together on the growth of Colletotrichum gloeosporioides (Penz.) Penz. and Sacc. causing inflorescence die back in arecanut

Colletotrichum gloeosporioides is a destructive pathogen of many crop species causing diseases in many annual, biennial and perennial plants. A study was undertaken to find out the effect of biological and chemical agents together on the growth of C. gloeosporioides causing inflorescence die back in arecanut at the Department of Plant Pathology, CPCRI, Kasaragod. To reduce the release of chemical pesticides to the environment, integrated control strategies have been adopted extensively by combining both bioagents and chemical agents. So in the present study in vitro experiments were conducted with two compatible Trichoderma sp. viz., Trichoderma virens and Trichoderma viride and fungicides viz. Blitox 50 W and Mixol 72. The results indicated that all the treatments had a significant inhibitory effect on the growth of C. gloeosporioides and reduced its colony diameter. High percent inhibition was found when 0.05% of Mixol 72 was used with T. virens (87.61%). The least inhibition was shown by T. virens+0.05% Blitox 50 W (80.95%). It is concluded that the combination of bioagents with fungicides provided higher disease suppression than achieved with fungicides and bioagents when used alone.     

Atomic solvation parameters in the analysis of protein-protein docking results.

Several sets of amino acid surface areas and transfer free energies were used to derive a total of nine sets of atomic solvation parameters (ASPs). We tested the accuracy of each of these sets of parameters in predicting the experimentally determined transfer free energies of the amino acid derivatives from which the parameters were derived. In all cases, the calculated and experimental values correlated well. We then chose three parameter sets and examined the effect of adding an energetic correction for desolvation based on these three parameter sets to the simple potential function used in our multiple start Monte Carlo docking method. A variety of protein-protein interactions and docking results were examined. In the docking simulations studied, the desolvation correction was only applied during the final energy calculation of each simulation. For most of the docking results we analyzed, the use of an octanol-water-based ASP set marginally improved the energetic ranking of the low-energy dockings, whereas the other ASP sets we tested disturbed the ranking of the low-energy dockings in many of the same systems. We also examined the correlation between the experimental free energies of association and our calculated interaction energies for a series of proteinase-inhibitor complexes. Again, the octanol-water-based ASP set was compatible with our standard potential function, whereas ASP sets derived from other solvent systems were not.     

Identification of significant pathways in gastric cancer based on protein-protein interaction networks and cluster analysis

Gastric cancer is one of the most common and lethal cancers worldwide. However, despite its clinical importance, the regulatory mechanisms involved in the aggressiveness of this cancer are still poorly understood. A better understanding of the biology, genetics and molecular mechanisms of gastric cancer would be useful in developing novel targeted approaches for treating this disease. In this study we used protein-protein interaction networks and cluster analysis to comprehensively investigate the cellular pathways involved in gastric cancer. A primary immunodeficiency pathway, focal adhesion, ECM-receptor interactions and the metabolism of xenobiotics by cytochrome P450 were identified as four important pathways associated with the progression of gastric cancer. The genes in these pathways, e.g., ZAP70, IGLL1, CD79A, COL6A3, COL3A1, COL1A1, CYP2C18 and CYP2C9, may be considered as potential therapeutic targets for gastric cancer.     

Effect of entomopoxvirus infection of the smaller tea tortrix, Adoxophyes sp. on the development of the endoparasitoid, Ascogaster reticulatus

Infection of Adoxophyes sp. (Lepidoptera: Tortricidae) larvae by an entomopoxvirus (AsEPV) adversely affected the development of the endoparasitoid, Ascogaster reticulatus Watanabe (Hymenoptera: Braconidae). Parasitoid larvae developing in AsEPV-infected hosts grew more slowly and spent more time in their hosts than did parasitoid larvae developing in noninfected hosts. Percentages of emergence of larval parasitoids that developed in AsEPV-infected hosts were significantly lower than those of parasitoids that developed in noninfected hosts. Parasitoid larvae in AsEPV-infected host perished when their hosts died of AsEPV infection. Significant numbers of parasitized and infected larvae exhibited apolysis to the final instar, whereas noninfected-parasitized larvae died in the penultimate instars due to emergence of parasitoids.     

Biological control of anthracnose (Colletotrichum gloeosporioides) in yam by Streptomyces sp.MJM5763

Aim: To find a suitable biocontrol agent for yam anthracnose caused by Colletotrichum gloeosporioides. Methods and Results: An actinobacterial strain, MJM5763, showing strong antifungal activity, multiple biocontrol and plant growth‐promoting traits was isolated from a yam cultivation field in Yeoju, South Korea. Based on morphological and physiological characteristics and analysis of the 16S rDNA sequence, strain MJM5763 was identified as a novel strain of Streptomyces and was designated as Streptomyces sp. MJM5763. Treatment with MJM5763 and the crude culture filtrate extract (CCFE) was effective in suppressing anthracnose in detached yam leaves in vitro and reduced incidence and severity of anthracnose in yam plants under greenhouse conditions. The CCFE treatment was the most effective of all the treatments and reduced the anthracnose severity by 85–88% and the incidence by 79–81%, 90 days after inoculation with the pathogen. CCFE treatment was also effective under field conditions and showed a reduction of 86 and 75% of anthracnose severity and incidence, respectively. Conclusion: Streptomyces sp. strain MJM5763 was effective in biocontrolling anthracnose in yam caused by C. gloeosporioides. Significance and Impact of the Study: Streptomyces sp. MJM5763 is a potential alternative to chemical fungicides for reducing yield losses to anthracnose in yam.     

内生真菌Colletotrichum sp. B501的寡糖提取物对黄花蒿发根中青蒿素生物合成的诱导

在黄花蒿(Artemisia annua L.)发根液体培养中,黄花蒿内生炭疽菌(Colletotrichum sp. B501)细胞壁寡糖提取物可促进发根青蒿素的合成.经寡糖诱导子(20 mg/L)处理4 d后,发根青蒿素含量达1.15 mg/g, 比对照高出64.29%.诱导作用与诱导子浓度、作用时间相关.诱导处理1 d后,X射线能谱分析表明黄花蒿发根细胞中Ca2+积累量显著增高,电镜观察发现液泡内出现高电子致密物,具活性氧清除作用的过氧化物酶表现出高活性(6.5 unit*min-1*g-1 FW).诱导处理第三天,细胞核DNA呈梯度条带降解,部分细胞出现程序化死亡.内生菌细胞壁寡糖提取物引起的生理反应有利于细胞中青蒿素的生物合成.     

内生真菌Colletotrichum sp. B501的寡糖提取物对黄花蒿发根中青蒿素生物合成的诱导(英文)

在黄花蒿 (ArtemisiaannuaL .)发根液体培养中 ,黄花蒿内生炭疽菌 (Colletotrichumsp .B5 0 1)细胞壁寡糖提取物可促进发根青蒿素的合成。经寡糖诱导子 (2 0mg/L)处理 4d后 ,发根青蒿素含量达 1.15mg/g ,比对照高出6 4 .2 9%。诱导作用与诱导子浓度、作用时间相关。诱导处理 1d后 ,X射线能谱分析表明黄花蒿发根细胞中Ca2 积累量显著增高 ,电镜观察发现液泡内出现高电子致密物 ,具活性氧清除作用的过氧化物酶表现出高活性 (6 .5unit·min-1·g-1FW)。诱导处理第三天 ,细胞核DNA呈梯度条带降解 ,部分细胞出现程序化死亡。内生菌细胞壁寡糖提取物引起的生理反应有利于细胞中青蒿素的生物合成。     

Genetic analysis of resistance to Puccinia striiformis f.sp. tritici in cv. Aflak at adult plant stage

In order to investigate heritability and gene action for yellow rust resistance in wheat, a resistance yellow rust cultivar Aflak was crossed to susceptible cultivar Avocet‘s’. Parents, F₁, F₂ and F₃ generations were cultured according to randomised complete block design with two replications in the research station of Gharakhil, Iran. Parents and other generations were inoculated with 70E0A+ race. Traits including severity and infection type were recorded and then coefficient of infection was calculated. For this trait, generations mean and variance analysis were performed and results showed that there were significant differences among generations for coefficient of infection. Results showed that in addition to additive and dominance effects, at least one kind of epistasis interaction (additive × additive) control this trait. Although additive and dominance effects control this trait, but with attention to generations variance analysis, the results showed that additive variance had important role to control this trait.     

Hemp sesbania (Sesbania exaltata) control in rice (Oryza sativa) with the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene formulated in an invert emulsion

In greenhouse and field experiments, an invert emulsion (MSG 8.25) was tested with dried, formulated spores of the bioherbicidal fungus Colletotrichum gloeosporioides f. sp. aeschynomene, a highly virulent pathogen of the leguminous weed Aeschynomene virginica (northern jointvetch), but considered ‘immune’ against another more serious leguminous weed, Sesbania exaltata (hemp sesbania). A 1:1 (v/v) fungus/invert emulsion mixture resulted in 100% infection and mortality of inoculated hemp sesbania seedlings over a 21-day period under greenhouse conditions. In replicated field tests of the fungus/invert formulation conducted in Stuttgart, AR, and Stoneville, MS, hemp sesbania was controlled 85 and 90%, respectively. These results suggest that this invert emulsion expands the host range of C. gloeosporioides f. sp. aeschynomene, with a concomitant improvement of the bioherbicidal potential of this pathogen.