Three previously undescribed metabolites from Cordyceps cicadae JXCH-1,an entomopathogenic fungus

Three previously undescribed compounds,cordycicadione(1),cordycicadin F(2),and 7-hydroxybassiatin(3),were isolated from the cultures of Cordyceps cicadae JXCH1,an entomopathogenic fungus.Their structures and relative configurations were elucidated primarily by NMR spectroscopic analysis.The absolute configurations of 1 and 2 were determined by ECD calculations.Single-crystal X-ray diffraction method was adopted to determine the absolute configuration of 3.Compound 2 is a polycyclic polyketide with an unusual enol ether moiety and a spiro ring.The compounds obtained in this study were subjected to screening their inhibition against the proliferation of the human lung cancer cell line A549 and the production of nitric oxide in murine macrophages RAW264.7.

Functional genomics in the rice blast fungus to unravel the fungal pathogenicity

A rapidly growing number of successful genome sequencing projects in plant pathogenic fungi greatly increase the demands for tools and methodologies to study fungal pathogenicity at genomic scale. Magnaporthe oryzae is an economically important plant pathogenic fungus whose genome is fully sequenced. Recently we have reported the development and application of functional genomics platform technologies in M. oryzae. This model approach would have many practical ramifications in design and implementation of upcoming functional genomics studies of filamentous fungi aimed at understanding fungal pathogenicity.

Brocaeloid D,a novel compound isolated from a wheat pathogenic fungus, Microdochium majus 99049

Microbes serve as the most important resource for drug discovery.During our screening for bioactive compounds from our natural products library,a pathogenic fungus,Microdochium majus strain 99049,from wheat was selected for further investigation.A new alkaloid named brocaeloid D(1),together with six previously characterized compounds(2–7)were identified.Compound 1 belongs to 4-oxoquinoline with C-2 reversed prenylation and a succinimide substructure.All the structures of these newly isolated compounds were determined by different means in spectroscopic experiments.The absolute configurations of 1 was further deduced from comparison of its CD spectrum with that of known compound 2.The bioactivities of these identified compounds were evaluated against several pathogenic microorganisms and cancer cell lines.Compounds 1–5 showed activity against HUH-7 human hepatoma cells with IC50 values of 80μg/mL.Compound 6 showed mild activity against HeLa cells(IC50=51.9μg/mL),weak anti-MTB activity(MIC=80μg/mL),and moderate anti-MRSA activity(MIC=25μg/mL),and compound 7 showed weak anti-MRSA activity(MIC=100μg/mL).

Two novel aliphatic unsaturated alcohols isolated from a pathogenic fungus Fusarium proliferatum

Phytopathogenic fungi have attracted great attention as a promising source for new drug discovery.In the progress of our ongoing study for bioactive natural products from an in-house phytopathogenic fungi library,a pathogenic fungus,Fusarium proliferatum strain 13294(FP13294),was selected for chemical investigation.Two novel aliphatic unsaturated alcohols named fusariumnols A and B(1 and 2),together with one previously characterized sesquiterpenoid lignoren(3)were identified.Structures of 1-3 were assigned by mass spectrometry and NMR spectroscopy.Their bioactivities were assessed against Staphylococcus epidermidis,S.aureus,and Methicillin-resistant S.aureus(MRSA).Compounds 1 and 2 exhibited weak antibacterial activity against S.epidermidis(MIC=100μM).

Studies on the Isolation, Identification and In Vitro Growth Rates of the Three Pathogenic Fungi from Panax notoginseng Cultivated in Wenshan Eparchy

Objective] The aim of this study was to simultaneously isolate and identify the main pathogenic fungi of the root rot, black spot and round spot from the Panax notoginseng plants cultivated in Wenshan Eparchy of Yunnan Province of China. [Method] The pathogenic fungi were isolated and purified by using potato dextrose agar （PDA） medium. The morphological identification was accomplished first according to the colony forms of the fungi when cultivated in vitro, then accord-ing to the symptom characteristics and colony forms of the re-isolated fungi in the reverse inoculation experiments. The molecular identification was performed accord-ing to the amplification and alignment of the internal transcribed space （ITS） se-quences of the fungi. The increases of the diameters and thickness of the colonies of the fungi cultivated in vitro were employed to indicate the growth rates of the fungi. [Results] The consistency of the colony forms and symptom characteristics and the 96%-99% similarities revealed in the ITS sequence alignments al proved that the main pathogenic fungi of the root rot, black spot and round spot of the P. notoginseng plants raised in Wenshan were Cylindrocarpon didymium, Alternaria panax and Mycocentrospora acerina, respectively. When cultivated in vitro in the same temperature, humidity and il umination, the increases of the colony diameters and thickness of C. didymium were the highest, fol owed by those of A. panax, then those of M. acerina. During different cultivation periods, the differences of the colony diameters and thickness of the three fungi al reached extremely significant level. However, at the same cultivation time, the differences of the diameters and thickness among the three fungi only reached significant level. [Conclusion] The main pathogenic fungi which result in the root rot, black spot and round spot of the P. notoginseng in Wenshan are C. didymium, A. panax and M. acerina, respec-tively. When these three diseases break out at the same time, the root rot wil spread fastest, fol owed orderly by the black spot and the round spot.

安徽药用牡丹炭疽病病原菌鉴定

牡丹(Paeonia suffruticosa Andr.)是芍药科植物,为多年生落叶灌木,具有很高的观赏和药用价值。因其风姿华丽、色彩艳丽、品种繁多、深受大家喜爱,是中国传统名花和世界著名花卉之一。其根皮也被称为丹皮,具有抗炎、抑制血小板、止痛、清热等作用,是六味地黄丸等著名中成药的主要配方,也是饮片中的常用品[1-2]。近年来,随着牡丹种植面积的不断扩大,造成牡丹病害的大面积发生,已给牡丹生产带来严重影响。

Secretome profiling reveals temperature-dependent growth of Aspergillus fumigatus

Aspergillus fumigatus is a ubiquitous opportunistic fungus. In this study, systematic analyses were carried out to study the temperature adaptability of A. fumigatus. A total of 241 glycoside hydrolases and 69 proteases in the secretome revealed the strong capability of A. fumigatus to degrade plant biomass and protein substrates. In total, 129 pathogenesis-related proteins detected in the secretome were strongly correlated with glycoside hydrolases and proteases. The variety and abundance of proteins remained at temperatures of 34°C–45°C. The percentage of endo-1,4-xylanase increased when the temperature was lowered to 20°C, while the percentage of cellobiohydrolase increased as temperature was increased, suggesting that the strain obtains carbon mainly by degrading xylan and cellulose, and the main types of proteases in the secretome were aminopeptidases and carboxypeptidases. Only half of the proteins were retained and their abundance declined to 9.7% at 55°C. The activities of the remaining β-glycosidases and proteases were merely 35% and 24%, respectively, when the secretome was treated at 60°C for 2 h. Therefore, temperatures >60°C restrict the growth of A. fumigatus.