Purification and Properties of a New l-Fucose-specific Lectin Produced by Streptomyces No. 100–2

The inhibitory effects of 3-nitro-2,4,6-trihydroxybenzamide derivatives on human 5-lipoxygenase (5-LO), a key enzyme in arachidonic acid cascades, were examined using 5-LO produced by Escherichia coli. Some of the tested compounds inhibited the conversion of arachidonic acid to 5-hydroperoxy-6,8,11,14-eicosatetraenoic acid (5-HPETE), and in particular the N-phenylbutyl derivative was about 30 times more active (IC₅₀ = 35 μm) than caffeic acid (IC₅₀ = 1000 μm), a known selective 5-LO inhibitor.     

Identification and characterization of the biotechnological potential of a wild strain of Paraconiothyrium sp

The isolation and characterization of fungal strains from poorly described taxa allows undercover attributes of their basic biology useful for biotechnology. Here, a wild fungal strain (CMU‐196) from recently described Paraconiothyrium genus was analyzed. CMU‐196 was identified as Paraconiothyrium brasiliense by phylogenetic analysis of the rDNA internal transcribed spacer region (ITS). CMU‐196 metabolized 57 out of 95 substrates of the Biolog FF microplates. Efficient assimilation of dextrins and glycogen indicates that CMU‐196 is a good producer of amylolytic enzymes. It showed a remarkably assimilation of α‐d ‐lactose, substrate described as inducer of cellulolytic activity but poorly assimilated by several fungi. Metabolically active mycelium of the strain decolorized broth supplemented with direct blue 71, Chicago sky blue and remazol brilliant blue R dyes. The former two dyes were also well removed from broth by mycelium inactivated by autoclaving. Both mycelia had low efficiency for removing fuchsin acid from broth and for decolorizing wastewater from the paper industry. CMU‐196 strain showed extracellular laccase activity when potato dextrose broth was supplemented with Cu⁺², reaching a maximum activity of 46.8 (±0.33) U L^?1. Studied strain antagonized phytopathogenic Colletotrichum spp. fungi and Phytophthora spp. oomycetes in vitro, but is less effective towards Fusarium spp. fungi. CMU‐196 antagonism includes overgrowing the mycelia of phytopathogens and growth inhibition, probably by hydrosoluble extracellular metabolites. The biotechnological potential of strain CMU‐196 here described warrants further studies to have a more detailed knowledge of the mechanisms associated with its metabolic versatility, capacity for environmental detoxification, extracellular laccase production, and antagonism against phytopathogens. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:846–857, 2018     

我国首例Paraconiothyrium cyclothyrioides感染致眼内炎的相关研究

目的报道我国首例由Paraconiothyrium cyclothyrioides引起的真菌性眼内炎,并分析其生物学特征、感染途径及治疗方法。方法通过形态学鉴定、生长温度试验、ITS测序等方法对我院1株眼外伤患者左眼前房沉积物中培养分离到的丝状真菌进行鉴定。结果该丝状真菌在PDA平板上在25℃生长快速,可见灰橄榄色周边有白色绒毛状菌落,表面皱褶,35℃生长缓慢,可见黄豆大小白色凸起菌落;25℃及35℃培养后镜下可见大量结节状菌丝,未见分生孢子,属于不产孢株;ITS测序结果为Paraconiothyrium cyclothyrioides。结论本病例是国内首次报导的由Paraconiothyrium cyclothyrioides引起的真菌性眼内炎。     

共生真菌Paraconiothyrium brasiliense化学表观遗传修饰研究

对昆虫中华剑角蝗肠道共生真菌Paraconiothyrium brasiliense的发酵产物进行化学表观遗传修饰研究。在马铃薯-葡萄糖培养基的基础上,添加组蛋白去乙酰化酶抑制剂辛二酰双羟肟酸(SBHA)或DNA甲基化转移酶抑制剂(5-氮杂胞苷),结果发现通过添加0.5mmol/L的SBHA,该真菌的发酵产物的结构类型发生较大变化,并从中新发现了1个吡啶酮类化合物(化合物1)。该类型的化合物为首次从该属菌株中获得,推测可能在SBHA的胁迫下,激活了该菌株的沉默基因,从而产生了新的代谢产物。     

Five Sesquiterpenes from Paraconiothyrium sp. and Their Anti-inflammatory Activity

Five eremophilane sesquiterpenes including three new ones, named paraconions A–C ( 1 – 3 ), were isolated from an endophytic fungus, Paraconiothyrium sp. from Artemisia selengensis. The structures of these new compounds were established based on spectroscopic methods, including nuclear magnetic resonance (NMR), ultraviolet (UV), and infrared (IR) spectroscopy, as well as high resolution electrospray ionization mass spectrometry (HR-ESI-MS). An anti-inflammatory assay indicated that paraconion B ( 2 ) inhibited lipopolysaccharide-induced nitric oxide (NO) production in RAW 264.7 cells, with an IC₅₀ value of 51.7 μM. The compounds discovered in this study will enrich the structural types of secondary metabolites of the endophytic fungus Paraconiothyrium sp.