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1.
An antibiotic complex comprising four components (A, B, C, and X) was extracted from a native solution and mycelium of Streptomyces werraensis 1365T. The components were purified by column and thin-layer (TLC) chromatographic procedures to study their physicochemical and biological properties. The results were used to identify the substances isolated. The preliminary data allowed us to identify the components X, A, and B as the previously described compounds undecylprodigiosin, anisomycin, and copiamycin, respectively, whereas component C is a natural compound, which probably has never been described. 相似文献
2.
The genera of Acanthocinini which have males with antennomere III modified are discussed and redefined, a key to identify them is provided. Additionally, Alcathousites Gilmour, 1962 is proposed as a junior synonym of Xenocona Gilmour, 1960, and the following five new combinations are proposed: Xenocona asperipennis (Fairmaire & Germain, 1859) n. comb.; X. forsteri (Tippmann, 1960) n. comb.; X. penicillata (Monné, 1990) n. comb.; X. senticosa (Monné & Martins, 1976) n. comb.; and X. superstes (Erichson, 1847) n. comb. Moreover, a new species from Colombia (Huila) is described and illustrated, Xenocona antonkozlovi n. sp., and the male of X. penicillata is illustrated for the first time. 相似文献
3.
Abstract A comparative cytogenetic analysis showed that B. antartandica, B. leptopus, B. nibaldoi and B. taeniata share the same diploid number 2n = 26, but not the same fundamental number (FN), which was 52 in B. leptopus and 50 in the other three species. The karyotype of B. nibaldoi, including C‐band patterns and locations of the NORs, are described for the first time. The C‐band patterns were species‐specific and were helpful in distinguishing taxa. Batrachyla leptopus can be distinguished from its congeners by the absence of telocentric chromosomes and by secondary constrictions in the long arms of pair 6 and short arms of pairs 7 and 11. The chromosomal data suggest that Batrachyla might be a paraphyletic genus. 相似文献
4.
ObjectivesTo identify immunogenic proteins of C. botulinum type B secretome by immunoproteomic analysis. ResultsIn the present study, an attempt was made to elucidate the vaccine candidates/diagnostic molecules against botulism using immuno proteomic approach. C. botulinum type B secretome was elucidated when it was grown in TPGY as well as CMM media. Predominant 51 proteins were identified in both the media using 2-DE and mass spectrometry analysis. 2D gels (CMM & TPGY) were probed with respected proteins mice antiserum and obtained 17 and 10 immunogenic proteins in TPGY as well as CMM media respectively. Hypothetical protein CLOSPO_00563, ornithine carbamoyl transferase, FlaA, molecular chaperone GroEL and secreted protease proteins were found as the common immuno dominant proteins in both media. Polyclonal Antibodies raised against C. botulinum types A and E showed cross-reactivity with secretome C. botulinum type B at the lowest dilution (1:1000) but did not show cross reactivity with highest dilution (1:30,000) with C. botulinum type B secretome. Polyclonal antibodies against C. botulinum type F secretome did not show cross reactivity with C. botulinum type B secretome. ConclusionsIdentified immunogenic proteins can be used as vaccine candidates and diagnostic markers for the infant and wound botulism but common immunogenic proteins may be the best vaccine candidate molecule for development of vaccine as well as diagnostic system against the infant and wound botulism. 相似文献
5.
【背景】土传病害是世界农业可持续发展的关键限制因子,在我国蔬菜和中药材上发生日趋严重,引起严重的连作障碍。生物防治对环境和农产品安全,是目前研究的热点和重点。【目的】明确对土传病原菌具有广谱抗菌活性菌株JJYY的种类及其防控效果和主要抗菌产物,为新型生物农药开发奠定基础。【方法】结合扫描电镜观察、生理生化分析和16S rRNA基因扩增测序技术鉴定菌株JJYY。分别利用比浊法和菌丝生长抑制法测定该菌提取物对4种土传病原细菌和5种土传病原真菌的 EC50,利用盆栽试验评价对番茄青枯病等病害的防控效果。利用二代Illumina NovaSeq与三代PacBio Sequel相结合测序技术对菌株JJYY进行全基因组测序,使用PGAP等软件进行基因注释等分析,利用反相制备液相色谱和质谱初步分离鉴定抗菌物质。【结果】菌株JJYY是一株贝莱斯芽孢杆菌( Bacillus velezensis),该菌提取物对4种土传细菌和5种土传真菌的 EC50分别为0.940-1.092 mg/mL和2.733-3.678 mg/mL。对番茄青枯病、菊花根腐病和辣椒枯萎病的最高防效在80.00%-87.74%之间,与化学药剂链霉素或噁霉灵无显著差异( P>0.05)。该菌基因组大小为3 929 792 bp,编码3 895个基因,与 B.velezensis JS25R和 B.subtilis 168具有3 445个和2 997个同源编码基因。预测该基因组共有12个次级代谢产物合成功能基因簇。从该菌株提取物中共分离出9种抗菌组分,其中2个初步判定为已知大环内酯类抗生素macrolactin D和7-O-malonyl-macrolactin A。【结论】菌株JJYY是一株对土传病原细菌和真菌病害均有较高防效的贝莱斯芽孢杆菌,该菌基因组与已知贝莱斯芽孢杆菌不同,并产生多种已知和未知的抗菌物质,继续深入分析鉴定其抗菌物质和抗菌机制将为开发新型高效的生物农药奠定良好基础。 相似文献
6.
Coat protein genes of six members of the genus Allexivirus, Garlic viruses ‐A, ‐B, ‐C, ‐D, ‐E and ‐X, were over‐expressed in bacteria and used to prepare polyclonal antibodies. In western blot analysis, Garlic virus D (GarV‐D) and GarV‐E were closely related serologically and there were weaker relationships between some other pairs, particularly GarV‐E with GarV‐A, GarV‐X with GarV‐A, GarV‐X with GarV‐B and GarV‐X with GarV‐C. Sequence analysis suggested that there was no simple relationship between amino acid identity and serological properties. 相似文献
7.
Abstract An efficient synthesis of 5′-nor carbocyclic ribavirin ( 4) is described in 13 steps from conveniently available (+)-(1 R,4 S)-4-hydroxy-2-cyclopenten-1-yl acetate ( 6). Compound 4 was evaluated against the following viruses: herpes simplex type 1 and 2, vaccinia, cowpox, smallpox, Ebola, hepatitis B, hepatitis C, adenovirus type 1, influenza A (H1N1 and H3N2), influenza B, parainfluenza type 3, Pichinde, Punta Toro A, respiratory syncytial, rhinovirus type 2, Venezuelan equine encephalitis, yellow fever, and West Nile. No activity was found nor was there any cytotoxicity to the viral host cells. 相似文献
8.
The genus Xenocylapus Bergroth, 1922 is revised. Nine new species, Xenocylapus aculeatus sp. nov., X. aquilonius sp. nov., X. bicolor sp. nov., X. globulus sp. nov., X. heissi sp. nov., X. panamaensis sp. nov., X. serrulatus sp. nov., X. tenuis sp. nov., and X. waorani sp. nov., are described from Brazil, Honduras, Mexico, and Panama. New genus and species Henryfulvius gracilis gen. nov., sp. nov. is described from Ecuador. Illustrations of the male genitalia, color photographs of dorsal and lateral views of the adult of most species, scanning electron micrographs of selected structures of X. tenuis, and keys to species of the genus Xenocylapus are provided. 相似文献
9.
【背景】兰茂牛肝菌(Lanmaoaasiatica)等外生菌根真菌的子实体形成和发育机制仍然未知。【目的】揭示调控子实体发育的关联物质。【方法】同时运用核磁共振、气相质谱和液相质谱3种代谢组学技术,分析兰茂牛肝菌纯培养8d原基(Y8)与野生子实体(Z0)的小分子物质。【结果】Y8及Z0分别共指认出451、473种化合物;Y8vs.Z0,有362种显著或极显著上调(206种)及下调(156种)差异物质,其涉及47条调控通路。【结论】推测通过9条主要通路完成物质的深度转化及调控,极显著上调及下调差异物质如牛肝菌素可能对子实体的发育起着一定的调控作用,3种方法互相补充扩大了检测的泛度及灵敏度,这为探究兰茂牛肝菌子实体发育机理及人工培养提供了一定的理论参考。 相似文献
10.
The antimicrobial activity of five samples of Taxandria fragrans essential oil was evaluated against a range of Gram‐positive ( n= 26) and Gram‐negative bacteria ( n= 39) and yeasts ( n= 10). The majority of organisms were inhibited and/or killed at concentrations ranging from 0.06–4.0% v/v. Geometric means of MIC were lowest for oil Z (0.77% v/v), followed by oils X (0.86%), C (1.12%), A (1.23%) and B (1.24%). Despite differences in susceptibility data between oils, oils A and X did not differ when tested at 2% v/v in a time kill assay against Staphylococcus aureus. Cytotoxicity assays using peripheral blood mononuclear cells demonstrated that T. fragrans oil was cytotoxic at 0.004% v/v but not at 0.002%. Exposure to one or more of the oils at concentrations of ≤0.002% v/v resulted in a dose responsive reduction in the production of proinflammatory cytokines IL‐6 and TNF‐α, regulatory cytokine IL‐10, Th1 cytokine IFN‐γ and Th2 cytokines IL‐5 and IL‐13 by PHA stimulated mononuclear cells. Oil B inhibited the production of all cytokines except IL‐10, oil X inhibited TNF‐α, IL‐6 and IL‐10, oil A inhibited TNF‐α and IL‐6, oil C inhibited IL‐5 and IL‐6 and oil Z inhibited IL‐13 only. IL‐6 production was significantly inhibited by the most oils (A, B, C and X), followed by TNF‐α (oils A, B and X). In conclusion, T. fragrans oil showed both antimicrobial and anti‐inflammatory activity in vitro, however, the clinical relevance of this remains to be determined. 相似文献
11.
The structure and conformational stability of vinyl selenonyl fluoride, chloride and bromide CH 2=CH–SeO 2X (X is F, Cl and Br) were investigated using density functional B3LYP/6-311+G** and ab initio MP2/6-311+G** calculations. From the calculations the molecules were predicted to exist only in the non-planar gauche
conformation with the vinyl C=C group almost eclipsing one of the selenonyl Se=O bonds as a result of conjugation between the two moieties. Single-minimum potential scans were calculated at the DFT level for the molecules. The vibrational frequencies were computed using B3LYP/6-311+G**. Normal coordinate calculations were then carried out and potential energy distributions were calculated for the three molecules in the
gauche conformation. Figure Potential function for the asymmetric torsion in vinyl selenonyl fluoride ( dotted line), chloride ( dashed line) and bromide ( solid line) as determined at the DFT-B3LYP/6-311+G** level 相似文献
12.
AbstractIn the Plains periphery of the Central Area, Missouri, extensive preceramic remains are found. Well recognized complexe s with Paleo-Indian connections are Nebo Hill, Sedalia, Graham Cave Levels 6-4, andArnoldResearch Cave. Radiocarbon dates range from 7738 B. C. to 4322 B. C. Other preceramic complexes described from excavations include the Hatten Mound component and the Lincoln County burial site, in the Northwest Prairie; Blackwell Component A in the Ozark Highland; and the Jakie L2 and L3 components dated at 5112 B. C. to 4422 B. C. in the Southwest Drainage. Surface collections from all areas indicate preceramic occupations. 相似文献
13.
For the first time in 1989 citrus bacterial canker disease has seen on Citrus
aurantiifolia in southern Iran. A total of 43 strains from affected citrus trees, ten strains from South Korea and representative from
all known five pathotypes of Xanthomonas axonopodis pathogenic on citrus trees were used in this study. Isolated strains from Iran were indistinguishable by phenotypic, FAMEs,
and SDS-PAGE analyses but showed different host range. First group were pathogenic on all tested citrus seedlings including
C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, Poncirus trifoliata X C. paradisi, C. aurantium, C. paradise, C. medica, P. trifoliate, C. grandis, C. sinensis, C. reticulate and C. sinensis X P. trifoliate. Pathogenicity of the second group were limited to C. aurantiifolia, C. limettioides, C. limon, C. jambhiri, P. trifoliata X C. paradis, and C. aurantium. Among the strains studied by AFLP fingerprinting six clusters were found. These clusters were: (1) strains of pathotype C;
(2) strains of pathotypes B and D; (3) strains of pathotype A together with the main group of the Iranian strains; (4) strains
isolated from Korea; (5) strains of pathotype E; and (6) seven strains from Iran which made a completely separate cluster.
Strains from pathotypes B and D could not be differentiated by AFLP. The tested Iranian strains belongs to the two different
groups and strains from Korea grouped as a subcluster from main cluster of Iranian strains belong to the pathotype A. 相似文献
14.
【背景】昆虫是世界上种类最多、肠道菌群资源最丰富且多样的动物类群之一。昆虫肠道微生物具有产生活性次级代谢产物的能力,是活性天然产物的重要来源。【目的】研究药用昆虫喙尾琵琶甲( Blaps rynchopetera)成虫肠道来源链霉菌( Streptomyces sp.) BPA71的次级代谢产物及其生物活性。【方法】利用正相硅胶柱色谱、葡聚糖凝胶Sephadex LH-20柱色谱等方法分离纯化该菌株的发酵粗提物,采用牛津杯法进行抗菌活性追踪,确定抗菌活性部位,通过ESI-MS、NMR等波谱数据分析对化合物结构进行鉴定,采用微量肉汤稀释法测定最低抑菌浓度(minimal inhibitory concentration, MIC),采用MTS法测定抗肿瘤活性。【结果】从 Streptomyces sp. BPA71的固体发酵提取物中共分离得到4个已知化合物,通过对比核磁数据确定为糠酸甲酯( 1)、吡咯甲酰胺A ( 2)、吡咯甲酰胺B ( 3)和吲哚-3-乙酸甲酯( 4)。抗菌活性结果显示化合物 2具有广谱抗菌活性。此外,化合物 2对宫颈癌细胞HeLa、肺癌细胞A549、肝癌细胞SMMC-7721、乳腺癌细胞MDA-MB-231和结肠癌细胞SW480这5株肿瘤细胞均有明显的抑制活性。【结论】喙尾琵琶甲肠道来源 Streptomyces sp. BPA71可产生丰富的生物活性物质,该研究结果为进一步挖掘喙尾琵琶甲肠道链霉菌的活性天然产物奠定了基础,同时丰富了人们对喙尾琵琶甲肠道微生物的认识。 相似文献
15.
The complex of pesticidal metabolites produced by Streptomyces griseus LKS-1 consists of a peptide antibiotic ( A), nonactic acids ( B), macrotetrolides ( C), pyrrolizines ( D), and of cycloheximide. The latter unwanted phytotoxic compound was eliminated by treatment with mutagens. Combined approaches,
including both genetic and physiological manipulations, resulted in the following alterations in the biosynthetic capacity:
( 1) A more than 80-fold increase in the production of C under a substantial decrease in the yields of A, B and D, the ratio of the components of C being steered toward the required more active ones; ( 2) a more than 300-fold increase in the production of B under suppression of the formation of A and C: ( 3) a 10-fold increase in the yields of D under suppression of A and C; ( 4 a significant increase in the yields of A with eliminating B, C and D. The level of inorganic phosphate in fermentation media and the sensitivity of the organism to carbon catabolite repression
were important factors participating in the regulation of the above biosynthetic processes. 相似文献
16.
Summary Three new trechine species of the genus Pilosaphaenops Deuve & Tian, 2008, P. qianzhii n. sp. from cave Lubian Dong in Pingtang County, southern Guizhou Province, P. mengzhenae n. sp. and P. weiguofui n. sp. from cave Xia Dong in Nandan County, and cave Shenlong Gong in Huanjiang County respectively, northern Guangxi Zhuang Autonomous Region, are described and illustrated. A key to all known species of this genus is also provided. http://www.zoobank.org/urn:lsid:zoobank.org:pub:170C467F-5421-49AD-B1B1-091D8BD58B88 相似文献
17.
【背景】香蕉枯萎病是香蕉的顽固性疾病,制约着香蕉产业的发展,因此,筛选出对香蕉枯萎病菌(尖孢镰刀菌古巴专化型4号生理小种,简称Foc4)具有抑制活性的生防菌株具有重要意义。【目的】分离香蕉林土壤样品中放线菌并进行物种的初步鉴定,测定其对包括香蕉枯萎病致病菌的7种病原菌的拮抗活性,获得高活性菌株,以获得解决香蕉枯萎病的生物防治策略。【方法】采集多份广西地区香蕉林土壤样品,采用超声波等手段对其预处理,设置多种特异性培养基从中分离放线菌资源,对获得的放线菌进行基于16SrRNA基因序列的物种鉴定,以7种病原菌为靶标,采用平板对峙法从中筛选抑菌活性菌株,最后采用菌丝生长速率法对Foc4的抑菌率进行测定。【结果】从香蕉林土壤中分离出138株放线菌均为链霉菌,其中5株为潜在新种,分别为X1085、X1052、X2052、X3059和X4046;筛选出具有抑菌活性的菌株77株,阳性率为55.8%。20株对Foc4具有抑制活性,其中4株拮抗效果明显,抑制率大于80%,菌株X4050的抑菌率高达93.76%。【结论】初步明确了香蕉林土壤中可培养放线菌的物种信息,其中部分放线菌为未知物种,活性分析显示一半... 相似文献
18.
The structure of liquid hydrocarbons and fatty acids produced by the green alga Botryococcus was identified. Two representatives of this alga, Botryococcus braunii Kütz, strain IPPAS H-252, introduced into culture earlier and an organism isolated for the first time from the Shira Lake, were used for this identification. Fatty acid composition of B. braunii, strain H-252, lipids was characterized by a high content of trienoic acids of C16–C18 series. The hydrocarbon composition of this strain was represented by straight-chain and branched-chain C14–C28 components; long-chain linear aliphatic C20–C27 hydrocarbons (54.4%) and 2,6,10,14-tetramethylhexadecane (20.5%) predominated among them. The strain H-252 differed in its fatty acid and hydrocarbon composition from the strains described earlier as Botryococcus braunii. The fatty acid composition of the Botryococcus isolate was represented mainly by C12–C32 saturated and monoenoic acids. The hydrocarbons formed by this isolate were represented by dienoic and trienoic components. C29 (48.9–56.3%) and C31 (11.1–16.3%) hydrocarbons predominated among the C23–C31 dienoic hydrocarbons, and C27, C29, and C31 trienoic hydrocarbons comprised 2.5–2.6% of total hydrocarbons. This type of hydrocarbons and the lipid fatty acid composition were characteristic for the race A of B. braunii. 相似文献
19.
AbstractA new Inner Mongolian endemic species, Bryoerythrophyllum neimonggolicum X.-L.Bai & C.Feng is described and illustrated from China. It is characterized by lingulate to broad-lanceolate leaves with obtuse or rounded apex, leaf margins broadly recurved to revolute to near the apex, bulging laminal cells, basal cells with thickened walls and the absence of lax and enlarged basal cells. This species is compared with closely related species and its ecology is discussed. 相似文献
20.
Summary In the lipase-catalyzed double enantioselective transesterification between the meso-diol 1 and the racemic 2,2,2-trifluoroethyl 2-chloropropanoate ( rac- 2) by the immobilized lipase preparation SP 382 from Candida antarctica, consisting of the components A and B, component B only is responsible for the enantioselectivity. 相似文献
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