一种云南红豆杉内生真菌的分离

本文首次报道从云南红豆杉树皮中分离出一种内生真菌,并用薄层支析技术对该真菌培养物进行了分析,初步结果表明该真菌能合成抗癌药物紫杉醇。     

一种云南红豆杉内生真菌的分离

本文首次报道从云南红豆杉(Taxus yunnanensis)树皮中分离出一种内生真菌,并用薄层层析技术对该真菌培养物进行了分析,初步结果表明该真菌能合成抗癌药物紫杉醇。     

三种红树林植物健康与非健康叶片中真菌的比较

红树林叶片感染真菌后可能会向非健康状态变化,为了比较三种红树林植物海漆、秋茄和桐花树健康与非健康叶片真菌类群,明确其中真菌类群的差异,该研究从广西茅尾海红树林自然保护区采集海漆、秋茄和桐花树健康与非健康叶片,对叶片中真菌分离纯化并进行形态学鉴定,提取真菌的DNA,采用RAPD多样性、ITS序列对真菌进行分子鉴定。经过初步分析,从海漆、秋茄和桐花树中共分离到157株真菌,经过形态学和RAPD分析,可能为19种不同的真菌。采用真菌ITS序列对19种真菌代表性菌株进行分析,结果表明:19种真菌都属于子囊菌门,有15株与已有的真菌ITS序列相似性在97%以上;有4株相似性低于95%,可能为新种。海漆健康和非健康叶片分别分离到真菌7种和5种,健康叶片含了非健康叶片中所有真菌;秋茄健康和非健康叶片分离到真菌1种和9种,且健康叶片中分离到的内生真菌Dothiorella aegiceri也包含于非健康叶片分离的真菌中;桐花树健康和非健康叶片分离到真菌1种和3种,且桐花树分离的内生真菌也是Dothiorella aegiceri,其包含于非健康叶片中分离到的真菌。该研究证明,海漆内生真菌同时也可能是植物病原菌,内生真菌与植物病原菌没有明显界限;另一方面,该研究发现秋茄和桐花树叶片的病变是由外部的病原真菌感染引起,感染的原因可能是昆虫叮咬红树林植物后留下了创口,这些创口有利于真菌的感染。     

粤北地区的抗肿瘤药用真菌资源研究

调查和统计了粤北地区具有抗肿瘤活性的药用真菌种类。结果发现有75种药用真菌具有抗肿瘤作用,为合理开发利用该地区的药用真菌资源提供了依据。     

中国野生发光真菌新记录种Neonothopanus nambi的分离、鉴定及其形态观察

【目的】在中国福建地区采集分离一株野生发光真菌,菌种编号为MRC-lf3,对其进行形态观察及分子鉴定以确定其分类地位,并观察其整个生活史的形态特征。【方法】采用组织分离技术获得野生发光真菌纯培养物,结合形态学及ITS进化分析确定该菌的分类地位,应用单反相机记录子实体不同生长时期的形态特征及发光情况。【结果】该发光真菌的菌丝、子实体、孢子的形态均与Neonothopanus nambi最为相似,ITS序列的进化分析结果也支持该发光真菌为Neonothopanus nambi。其子实体颜色深浅和发光强度均受到光照强度的影响,光照可使子实体颜色变暗、发光强度减弱。【结论】从福建省福州市采集分离获得一株大型野生发光真菌,经鉴定该菌为Neonothopanus nambi,是中国首次发现的Neonothopanus属真菌,该发现也将中国大陆的野生发光真菌总数增加至8种。     

一株蝉花虫草菌重寄生真菌的分离鉴定

报道了1种新的昆虫-昆虫病原菌-重寄生菌三级营养关系,其中蝉若虫被昆虫病原真菌蝉花Cordyceps chanhua感染,而蝉花又被重寄生真菌寄生.经形态学观察和分子生物学鉴定该重寄生真菌为寄生凹孢Syspastospora parasitica.柯赫氏法则验证结果表明:该重寄生真菌可以重寄生于蝉花Cordyceps ...     

真菌在兰科植物种子萌发生长中的作用及相互关系

本文从真菌在兰科种子萌发中的应用、真菌侵染的过程、种子和根系消化真菌的途径及共生真菌的分布等方面,综述了真菌与兰科植物种子萌发及菌根关系的研究进展,讨论了该研究的有关问题及真菌在兰科种子萌发中应用的前景。     

中国大型真菌分类学公民科学计划1.0

公民科学是指公众在职业科学家的引导下参与从事科学研究。大型真菌是在生活史中能够形成肉眼明显可见子实体的一类真菌的统称,具有重要的经济价值和生态功能,需要在分类学研究认识其物种多样性的基础上加以开发利用。大型真菌与公众生活息息相关,因此公众有认识这些大型真菌种类的意愿。另一方面,大型真菌物种多样性极高,仅依靠为数不多的职业分类学家难以在短期内全面认知我国大型真菌多样性并加以利用。此外,大型真菌子实体在简单预处理后便可被带到实验室进行分类学研究。综上,我们提议启动大型真菌分类学公民科学计划1.0。在该计划的框架下,公众主要负责大型真菌子实体的生境信息记录、拍照、采集、预处理和寄送。大型真菌子实体将被永久保藏于中国科学院微生物研究所菌物标本馆,并进行形态学检查和DNA分子测序。该公民科学计划预期将提升公众的科学素养,促进大型真菌分类学的发展,为该计划2.0版本的实施提供基础。     

一株银杏内生真菌代谢产物的初步研究

从银杏树皮内侧分离纯化获得6种类27株内生真菌。使用TLC、HPLC、HPLC/ESI-MSn方法对上述真菌胞内代谢产物进行研究,最终发现1株真菌菌株G3B经发酵后产生银杏内酯B等成分。经形态学初步鉴定该菌株为镰孢菌属(Fusarium)真菌。     

川八角莲内生真菌产鬼臼毒素类似物的初步研究

目的：从川八角莲中分离到产抗癌药物鬼臼毒素类似物的内生真菌。方法：采用薄层层析法(TLC)和高效液相色谱法(HPLC)对内生真菌的发酵产物进行分析检测。结果：分离到16株内生真菌,其中一株真菌(2BNO1)产鬼臼毒素类似物,经鉴定该真菌为牵连青霉(Penicillium implication)。结论：川八角莲个别内生真菌能产抗癌药物鬼臼毒素类似物。     

117例医院真菌感染分析及预防

目的 了解佛山市南海人民医院真菌感染的分布,探讨有效预防和控制真菌感染的措施。方法 对该院117例真菌感染病例作回顾性分析。结果 3583例送检标本中真菌检出率为3．27％（117／3583）,医院内真菌感染率为2．95％（106／3583）。分离出真菌以白色念珠菌为主（70／117．59．8％）、热带念珠菌次之（17／117,14．5％）、霉菌居第3位（9／117．7．69％）。药敏显示：5-氟胞嘧啶、两性霉素B和制霉素敏感率较高,分别为92．4％、93．3％和92．5％,咪康唑、酮康唑和益康唑敏感率较低．为52．0％、49．0％和36．0％。结论 医院内真菌感染占真菌感染绝大部分,感染真菌以白色念珠菌为主。感染部位以呼吸道为主;临床规范、合理使用广谱抗生素,加强消毒护理工作。是预防控制真菌感染发生的最有效措施。     

白腐菌对纸浆漂白的研究进展*

综述了白腐菌对纸浆的漂白作用。包括用于纸浆漂白的白腐菌类型,白腐菌漂白纸浆的纸浆类型,白腐菌漂白纸浆的工艺装置,以及微生物漂白存在的问题和前景。     

Selecting hyperparasites for biocontrol of Dutch elm disease

Hyperparasites in the form of cytoplasmic RNA elements have been proposed as a biological control agent for Dutch elm disease. We characterized the range of outcomes likely to follow the introduction of such an agent by modelling the resultant population dynamics as an ecological interaction between the wild, ''target'', fungus and the hyperparasitized ''control'' fungus. We used data from the 1970s epidemic of Dutch elm disease in the UK to parameterize the population dynamics of the target fungus, and considered the success of control across a wide range of possibilities for the lethality and transmissibility of the modified control fungus. We decomposed hyperparasite transmissibility into horizontal transmissibility (the ability to colonize previously unparasitized target fungal hosts) and vertical transmissibility (the ability of control fungus to establish new colonies). There is an invasion threshold for both horizontal and vertical transmissibility. As vertical transmission is further increased, there is another threshold at which the target fungus is eradicated because of competitive exclusion by the control fungus. In contrast, eradication by raising horizontal transmission may never succeed because the target fungus needs to be present to support new cases through this route. Between these two thresholds for invasion and exclusion, control and target fungus may coexist. Using a stochastic, spatially extended model, we showed that predictions of success based on high competitive ability of the control fungus (i.e. high vertical transmission) are likely to be more robust than those based on the high degree to which the control fungus can cause target fungus to be hyperparasitized (i.e. high horizontal transmission).     

四年间酵母样真菌感染的病原菌分布与耐药特征分析

目的了解临床酵母样真菌感染的流行特点及其耐药性,指导临床合理运用抗真菌药物。方法运用WHONET软件对中南大学湘雅三医院4年间临床分离出的酵母样真菌与其耐药进行回顾性分析。结果4年间临床酵母样真菌感染率由2002年的9.0%升至2005年的13.8%,白色念珠菌仍是引起临床感染的主要真菌,但其构成比由2002年的69.7%降至2005年的49.1%,而近平滑念珠菌的构成比4年间增加了9.5%,成为临床酵母样真菌感染的第二位病原菌。4年间临床酵母样真菌对唑类药物的耐药率增加了9.6%~16.8%。结论临床酵母样真菌引起的感染逐年增加,种类增多,对唑类药物的耐药情况日趋严重,应加强对临床真菌感染与耐药性情况的监测,以指导临床合理使用抗生素。     

Symbiotic fungi produce laccases potentially involved in phenol degradation in fungus combs of fungus-growing termites in Thailand

Fungus-growing termites efficiently decompose plant litter through their symbiotic relationship with basidiomycete fungi of the genus Termitomyces. Here, we investigated phenol-oxidizing enzymes in symbiotic fungi and fungus combs (a substrate used to cultivate symbiotic fungi) from termites belonging to the genera Macrotermes, Odontotermes, and Microtermes in Thailand, because these enzymes are potentially involved in the degradation of phenolic compounds during fungus comb aging. Laccase activity was detected in all the fungus combs examined as well as in the culture supernatants of isolated symbiotic fungi. Conversely, no peroxidase activity was detected in any of the fungus combs or the symbiotic fungal cultures. The laccase cDNA fragments were amplified directly from RNA extracted from fungus combs of five termite species and a fungal isolate using degenerate primers targeting conserved copper binding domains of basidiomycete laccases, resulting in a total of 13 putative laccase cDNA sequences being identified. The full-length sequences of the laccase cDNA and the corresponding gene, lcc1-2, were identified from the fungus comb of Macrotermes gilvus and a Termitomyces strain isolated from the same fungus comb, respectively. Partial purification of laccase from the fungus comb showed that the lcc1-2 gene product was a dominant laccase in the fungus comb. These findings indicate that the symbiotic fungus secretes laccase to the fungus comb. In addition to laccase, we report novel genes that showed a significant similarity with fungal laccases, but the gene product lacked laccase activity. Interestingly, these genes were highly expressed in symbiotic fungi of all the termite hosts examined.     

猪苓、伴生菌及蜜环菌共培养的形态学研究

本文对猪苓、伴生菌及蜜环菌两两共培养及三者共培养进行了宏观形态观察及细胞学水平上的研究。结果表明,猪苓与伴生菌共培养时,在二者之间形成一致密拮抗线,猪苓菌落表面菌丝分化产生大量菌丝束;猪苓与蜜环菌共培养时,猪苓能阻止蜜环菌菌索对其自身的进一步侵袭,互作区中的双方菌丝及菌索均停止生长;蜜环菌与伴生菌共培养时,蜜环菌能穿透整个伴生菌菌落,在伴生菌菌落下方产生大量分枝;三者共培养后,猪苓对蜜环菌的防御能力有所下降,伴生菌对蜜环菌的耐受力有所提高,蜜环菌产生的新分枝均向伴生菌一侧生长,猪苓与伴生菌之间并不形成致密拮抗线,只可见双方菌丝的白色交融区。 猪苓与伴生菌均能在蜜环菌菌索皮层上形成侵入位点。     

与盾叶薯蓣细胞共生培养的内生真菌分离及其生物学特性

从盾叶薯蓣根状茎中分离到一株与盾叶薯蓣细胞共生培养的内生真菌（RE0105）。测定了该菌ITS1-5．8S rDNA—ITS2序列并构建了系统发育树,发现RE0105与Libertella属形成一个类群,具有较近亲缘关系。该真菌能产生与宿主植物相同的代谢产物——薯蓣皂苷元。对RE0105培养特性研究表明：富含有机营养的培养基有利于其生长;盾叶薯蓣细胞提取物可明显刺激其生长;20μmol／L生长素NAA和2,4-D能够促进RE0105的生长。200μmol／L细胞分裂素KT和BA对RE0105生长具有一定的促进作用,但与生长素相比,细胞分裂素对RE0105生长的刺激作用较小。蔗糖、葡萄糖、果糖、乳糖、木糖和NH4NO3是RE0105生长的良好C源和无机N源,但NH4Cl和（NH4）2SO4对该菌生长具有明显抑制作用,并且显著影响其形态特征。     

Aspects of the symbiosis of the leaf-cutting ant Acromyrmex octospinosus (Reich) and its food fungus

Abstract. 1. Laboratory ants preferred eating whole ant fungus staphylae to hyphae, and did not feed on other fungi. Homogenized ant fungus staphylae and hyphae were equally acceptable liquid food but other homogenized fungi were not drunk extensively.
2. Various arthropod fungjvores preferred to feed on ant fungus rather than any other fungus tested. Some preferred hyphae to staphylae, some vice versa and others had no preference.
3. The ants attacked animals on the nest and reduced the numbers of fungivores on the fungus garden.
4. The ant fungus grew best at 24.5°C and hardly at all at 10°C or 37°C.
5. The ants did not necessarily choose material which supported the best fungus growth in sterile culture and readily accepted substrates on which the fungus did not grow at all. No learning behaviour was noted.
6. The ant X fungus symbiosis is discussed as an example of co-evolution, a product of an evolutionary feedback. The ant is supplied with a highly nutritious, readily acceptable food source in return for complex fungus-culture behaviour, providing protection from fungivores and competition from other saprophytic fungi.     

一株产苝醌光敏化合物的真菌成分分析

本文报道人工培养的一株菌寄生菌属Ｈｙｐｏｎｇｃｅｓｓｐ．真菌菌体化学成分的研究与分析结果,证明该菌主要次生代谢产物为醌类光敏色素,还含有较丰富的甘露醇和长链烷烃及其衍生物,是一株优良的具有实用开发价值的菌种。     

The relationship of endophytic fungi to the gametophyte of the fern Schizaea pusilla

Schizaea pusilla is a rare and threatened fern restricted in North America to acidic bogs of Nova Scotia, Newfoundland, and New Jersey. The gametophyte lives in close association with two endophytic fungi. To characterize the nature of this fern's relationship with these fungi, we introduced axenic gametophytes to bog soil for colonization. Following colonization, the endophytic fungi were isolated and reintroduced to axenic gametophytes. The gametophytes introduced to bog soil were colonized by an aseptate fungus that formed vesicles and arbuscules within the gametophyte. However, culture of colonized gametophytes produced two fungal isolates: an aseptate fungus (fungus B) and a septate fungus (fungus A). Upon reintroduction of fungal isolates to axenically grown gametophytes, the aseptate fungus demonstrated a positive growth response to the presence of the gametophytes and colonized the gametophytes without harm to the host. The septate fungus did not exhibit any specific recognition but contacted the gametophytes randomly, leaving a large percentage of the host nonviable. We propose that the relationship of the septate fungus to the gametophyte of S. pusilla is nonmycorrhizal while the relationship of the aseptate fungus to the gametophyte is mycorrhizal. Furthermore, based on lack of nutrient availability in local soils, formation of specialized structures in the gametophyte for harboring fungi, and dependence of the fern on fungal presence for completion of its life cycle, we propose that S. pusilla maintains an obligatory relationship with the aseptate mycorrhizal fungus.