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1.
【目的】调查发现我国土壤中稀有且重要的真菌资源。【方法】采用经典形态学及分子系统学方法对获得的菌株进行鉴定。【结果】从一养殖场含有猪粪的土样中分离获得一赛多孢EM12901菌株。其主要鉴别特征是:在查氏培养基上,绒状,灰白色至淡棕色。分生孢子梗单生或分支;单生的分生孢子梗常退化为产孢细胞。产孢细胞顶生或侧生,透明至半透明,薄壁,柱状或轻微膨大的烧瓶状,(3.5-45.0)μm×(1.5-3.0)μm;分生孢子顶生或侧生,单生,透明至半透明,光滑,椭圆形、倒卵圆形或近柱状,(4.3-14.0)μm×(2.5-5.5)μm。【结论】基于形态学及分子系统学方法相结合鉴定,赛多孢EM12901菌株为我国一新记录种,桔黄赛多孢Scedosporium aurantiacum Gilgado,Cano,GenéGuarro。  相似文献   

2.
【目的】对寄生鞘翅目幼虫蛴螬的虫生真菌标本GZUIFR-lgs-1进行描述和鉴定。【方法】基于形态特征比较结合系统发育分析进行鉴定。【结果】该种通过形态特征产孢细胞单生,透明,多数与营养菌丝成近直角,基部具疣且明显膨大(19-27)μm×(2.7-3.6)μm,颈部长(12.0-14.5)μm,顶端呈螺旋状扭曲,偶有再育;分生孢子透明、光滑,橘瓣状,单生或偶有双生,外具黏液,大小为(4.8-6.0)μm×(2.4-3.6)μm,而与被毛孢属已知种相区别。基于ITS位点的系统发育分析支持形态学鉴定的结果。【结论】综合形态特征比较及系统发育分析结果,该种为被毛孢属的一个新的分类单元,命名为雷公山被毛孢,Hirsutella leigongshanensis。  相似文献   

3.
Hirsutella tortricicola sp. nov.(菌株GZUIFR-hir090704)分离于寄生卷叶蛾科昆虫幼虫的真菌标本GZUIFR-kks-2。其主要形态特征为产孢细胞颈部具1-2个螺旋状结构且再育明显;分生孢子具黏液,橘瓣状,2.7-3.6×1.4-1.8μm。通过形态学比较和系统发育学分析确定H. tortricicola为被毛孢属新成员。  相似文献   

4.
报道了分离自土壤的一个弯颈霉属新记录种 ,即高山弯颈霉 (TolypocladiumnubicolaBissett)。其主要鉴别特征是 :①在查氏培养基上 ,2 5℃ ,14d ,直径达 30~ 35mm ,平展 ;②瓶梗直接着生于菌丝或简单的分生孢子梗上 ,有再育现象 ,基部拟椭圆形膨大或球形膨大 ,(2 .6~ 7.2 ) μm× (1.3~ 3.2 ) μm ,颈部细长 ,常弯曲 ,(3.0~6 .3) μm×0 .3μm ;③分生孢子单生 ,柱状至椭圆形 ,(1.6~ 3.8) μm× (0 .8~ 1.2 ) μm ,外无黏液层。  相似文献   

5.
从青海省格尔木的农田土壤中分离到一嗜角蛋白的金孢属新种——青海金孢。采用形态学和分子系统学对其进行了描述和鉴定,其主要鉴别特征是:侧生孢子较多,光滑,3.6-9×1.8-3.6μm,棒状至柱状,基痕宽>1.0μm;双细胞分生孢子存在,9-13×1.8-2.7μm,柱状;具间生孢子和厚垣孢子。  相似文献   

6.
【目的】巨疖蝙蛾Endoclita davidi(Poujade,1886)是雪峰虫草菌Ophiocordyceps xuefengensis的重要寄主。本研究分析了该虫线粒体DNA COI基因条形码,以在不同虫态及被虫草菌寄生的僵虫状态下能快速准确鉴定寄主种类。【方法】PCR扩增巨疖蝙蛾成虫(足一对,胸肌,翅基部)、卵(单粒)、幼虫(胸足一对)、蛹(少量体壁组织)及虫草僵虫(胸足或体壁)组织共计21个样品的COI基因片段(约658 bp)并进行测序和比对;以MEGA6.0软件的K2-P双参数模型计算种内及种间遗传距离;以邻接法(neighbor-joining,NJ)和最大简约法(maximum parsimony,MP)两种方法构建系统发育树。【结果】聚类分析与形态学鉴定结果一致,所纳入分析的20个样品均为同一物种,节点支持率可达99%。种内遗传距离为0.00%~1.08%,平均0.54%。与蝙蝠蛾科其他6种昆虫种间遗传距离为5.36%~13.31%,平均10.47%;种间遗传距离为种内遗传距离的19.39倍(10.47%vs 0.54%),而且种内与种间遗传距离没有重叠区域。【结论】基于mtDNA COI基因DNA条形码技术可以用于巨疖蝙蛾的快速准确鉴定,并对蝙蝠蛾科(Hepialidae)昆虫的分子系统发育分析有重要意义。  相似文献   

7.
张姝  崔宁波  赵宇翔  张永杰 《微生物学报》2019,59(12):2346-2356
【目的】分析蛹虫草是否存在核内线粒体DNA片段,比较蛹虫草线粒体DNA与细胞核DNA的碱基变异程度及所反映的菌株间的系统发育关系。【方法】通过本地BLAST或LAST对蛹虫草线粒体基因组和核基因组进行序列相似性搜索;从10个已知线粒体基因组的蛹虫草菌株中分别扩增7个细胞核蛋白编码基因片段,并与其在14个线粒体蛋白编码基因上的碱基变异情况进行比较。【结果】蛹虫草核基因组中存在5处较短的核内线粒体DNA片段,总长只有278bp。蛹虫草核DNA的变异频率整体上高于线粒体DNA。核DNA和线粒体DNA所反映的蛹虫草菌株间的系统发育关系存在显著差异。【结论】蛹虫草线粒体DNA与核DNA间不存在长片段的基因交流,二者变异频率不同,所反映的蛹虫草菌株间的系统发育关系也有差异。本研究增加了对蛹虫草线粒体与细胞核DNA进化关系的认识。  相似文献   

8.
一株采自贵州宽阔水的虫草,其主要特征为产孢细胞两型,分生孢子无色,光滑,肾形或长梭形,单个或多个包被于黏液层中。经形态特征及分子生物学比对鉴定,该种为中国新记录种—红蚁线虫草Ophiocordyceps myrmicarum D.R.SimmonsGroden。  相似文献   

9.
【目的】调查发现我国稀有但重要的虫生束梗孢类真菌。【方法】采用经典形态学及生态学特征对研究标本进行鉴定。【结果】在寄生鞘翅目昆虫的标本中,发现我国一拟多头束霉新记录种,金龟拟多头束霉Tilachlidiopsis scarabaei L.S.Olive,其形态特征为:寄主昆虫长约15 mm,宽4 mm。孢梗束下部深褐色,上部白色,长约36 mm,宽约1.8 mm,头状,可简单分枝。瓶梗锥形,少数棒状,顶端变细,长约19.4-25.9μm,宽1.1-2.2μm,在孢梗束的球状头部,呈栅栏状密集排列;在近头部的柄上瓶梗顶侧生于简单分枝的分生孢子梗上。分生孢子大多椭圆形,(2.2-3.2)μm×(1.1-2.2)μm;近柱形,(4.3-5.4)μm×(1.1-2.2)μm;少数球形,1.1-2.2μm。【结论】经文献检索和鉴定,金龟拟多头束霉为我国报道的新记录种。  相似文献   

10.
在贵州茂兰国家自然保护区发现寄生蚧壳虫的层束梗孢属真菌gzuifr-hym201307jk。主要特征为孢梗束灰白色单生,1417 mm×0.9 mm,产孢细胞柱状向上收缩变尖,顶部具有117 mm×0.9 mm,产孢细胞柱状向上收缩变尖,顶部具有13个叉状的产孢小颈,大小10.83个叉状的产孢小颈,大小10.814.0×4.314.0×4.35.4μm;分生孢子梭形,7.65.4μm;分生孢子梭形,7.610.8×4.310.8×4.35.4μm。经鉴定该真菌为中国新记录种——Hymenostilbe furcata。  相似文献   

11.
Although the architecture of tripartite multiple drug resistance (MDR) efflux pumps of Gram-negative bacteria has been well characterized, the means by which the components recognize each other and assemble into a functional pump remains obscure. In this study we present evidence that the C-terminal domain of the Pseudomonas aeruginosa OprM and the α-helical hairpin domain of Vibrio cholerae VceA play an important role in the recognition/specificity/recruitment step in the assembly of a functional, VceAB-OprM chimeric efflux pump. To our knowledge, this is the first evidence directly linking the C-terminal domain of an outer membrane efflux protein to its recruitment during the assembly of a tripartite efflux pump.  相似文献   

12.
心脑血管疾病大额住院消费统计分析   总被引:1,自引:1,他引:0  
通过对医院2004-2006年心脑血管疾病大额住院消费(消费大于50000元,以下简称大额消费)病例发病率高的前五种疾病的构成情况、药费、材料费消耗情况进行分析,认为加强大额病例中发病率高的病种的重点管理,是降低医疗费用的有效途径。建议制定常见病大额病种预定额付费方案和审查报销制度;采用适宜技术;控制药费,防止过度医疗,有效地遏制医疗费用的过快增长。  相似文献   

13.
J.Michael Gould  S. Izawa 《BBA》1974,333(3):509-524
1. By using dibromothymoquinone as the electron acceptor, it is possible to isolate functionally that segment of the chloroplast electron transport chain which includes only Photosystem II and only one of the two energy conservation sites coupled to the complete chain (Coupling Site II, observed P/e2 = 0.3–0.4). A light-dependent, reversible proton translocation reaction is associated with the electron transport pathway: H2O → Photosystem II → dibromothymoquinone. We have studied the characteristics of this proton uptake reaction and its relationship to the electron transport and ATP formation associated with Coupling Site II.

2. The initial phase of H+ uptake, analyzed by a flash-yield technique, exhibits linear kinetics (0–3 s) with no sign of transient phenomena such as the very rapid initial uptake (“pH gush”) encountered in the overall Hill reaction with methylviologen. Thus the initial rate of H+ uptake obtained by the flash-yield method is in good agreement with the initial rate estimated from a pH change tracing obtained under continuous illumination.

3. Dibromothymoquinone reduction, observed as O2 evolution by a similar flash-yield technique, is also linear for at least the first 5 s, the rate of O2 evolution agreeing well with the steady-state rate observed under continuous illumination.

4. Such measurements of the initial rates of O2 evolution and H+ uptake yield an H+/e ratio close to 0.5 for the Photosystem II partial reaction regardless of pH from 6 to 8. (Parallel experiments for the methylviologen Hill reaction yield an H+/e ratio of 1.7 at pH 7.6.)

5. When dibromothymoquinone is being reduced, concurrent phosphorylation (or arsenylation) markedly lowers the extent of H+ uptake (by 40–60%). These data, unlike earlier data obtained using the overall Hill reaction, lend themselves to an unequivocal interpretation since phosphorylation does not alter the rate of electron transport in the Photosystem II partial reaction. ADP, Pi and hexokinase, when added individually, have no effect on proton uptake in this system.

6. The involvement of a proton uptake reaction with an H+/e ratio of 0.5 in the Photosystem II partial reaction H2O → Photosystem II → dibromothymoquinone strongly suggests that at least 50% of the protons produced by the oxidation of water are released to the inside of the thylakoid, thereby leading to an internal acidification. It is pointed out that the observed efficiencies for ATP formation (P/e2) and proton uptake (H+/e) associated with Coupling Site II can be most easily explained by the chemiosmotic hypothesis of energy coupling.  相似文献   


14.
Gel permeation, preparative isoelectric focusing, and affinity chromatography were used to purify three inhibitors of proteolytic activity from perchloric acid extracts of last instar Galleria mellonella larvae. Electrofocusing experiments revealed three isoinhibitors with different isoelectric points: inhibitor I-1 with p1 of pH 5.6, inhibitor I-2, pH 7.7, and inhibitor I-3 (of small inhibitory activity), pH 8.6. By affinity chromatography on trypsin-Sepharose 4B the I-1 was purified 9.7 ×, but 71.1% of inhibitory activity was lost. Molecular mass of the inhibitory complex was 12,600 Da. I-1 and I-2 are relatively stable to heat at several pHs with minor stability at pH 10. I-1 and I-2 inhibit serine proteases about 2.5 times as much as sulfhydryl proteases. In the same ratio protease P-1 and protease P-2 from Metarhizium anisopliae are inhibited.  相似文献   

15.
Survival times and oxygen consumption rates have been determined for a benthic harpacticoid copepod, Thompsonula hyaenae (Thompson), when fed different algal diets. Nauplii and adults lived slightly longer on a diet of Navicula sp. than did those fed N. pelliculosa or a mixture of both naviculoid species. Mean numbers of harpacticoids hatched were significantly higher in cultures of N. pelliculosa. Metabolic rates of non-gravid females fed for one week on N. sp. were significantly lower than those fed N. pelliculosa or the mixture. There was no significant difference in oxygen uptake between animals fed N. pelliculosa and those fed the mixed culture. The smaller size and lower food energy content of N. pelliculosa are reflected in the higher respiratory rates of animals led this diatom species.Based on a thesis submitted in partial fulfillment of the M.S. degree in Marine Science at the University of South Carolina. Belle W. Baruch Institute for Marine Biology and Coastal Research Contribution No. 114. Research supported by the Oceanography Section, National Science Foundation, NSF Grant DES72-01573 A01.  相似文献   

16.
RUTH MACKLIN 《Bioethics》2010,24(5):211-217
Fast forward 50 years into the future. A look back at what occurred in the field of bioethics since 2010 reveals that a conference in 2050 commemorated the death of bioethics. In a steady progression over the years, the field became increasingly fragmented and bureaucratized. Disagreement and dissension were rife, and this once flourishing, multidisciplinary field began to splinter in multiple ways. Prominent journals folded, one by one, and were replaced with specialized publications dealing with genethics, reproethics, nanoethics, and necroethics. Mainstream bioethics organizations also collapsed, giving way to new associations along disciplinary and sub‐disciplinary lines. Physicians established their own journals, and specialty groups broke away from more general associations of medical ethics. Lawyers also split into three separate factions, and philosophers rejected all but the most rigorous, analytic articles into their newly established journal. Matters finally came to a head with global warming, the world‐wide spread of malaria and dengue, and the cost of medical treatments out of reach for almost everyone. The result was the need to develop plans for strict rationing of medical care. At the same time, recognition emerged of the importance of the right to health and the need for global justice in health. By 2060, a spark of hope was ignited, opening the door to the resuscitation of bioethics and involvement of the global community.  相似文献   

17.
The molecular mechanisms of change in the thermal stability of proteins modified with low molecular weight reagents are discussed. The choice of stabilization mechanisms to be used as a general strategy for increasing enzyme stability by chemical modification is addressed. Hydrophilization of nonpolar surface areas is the most simple and reliable approach to artificial stabilization of enzymes for use in applied biochemistry and biotechnology.  相似文献   

18.
19.
对不同地理分布的猪苓纯培养菌株进行了种性和酯酶同工酶的比较研究,结果表明,鸡爪苓(Z)纯培养菌株和猪屎苓(ZJ)纯培养菌株的种性有很大不同,两个纯培养菌株的酯酶同工酶酶带类型差异较大,亲缘关系较远。  相似文献   

20.
Summary It is proposed that the first entity capable of adaptive Darwinian evolution consisted of a liposome vesicle formed of (1) abiotically produced phospholipidlike molecules; (2) a very few informational macromolecules; and (3) some abiogenic, lipid-soluble, organic molecule serving as a symporter for phosphate and protons and as a means of high-energy-bond generation. The genetic material had functions that led to the production of phospholipidlike materials (leading to growth and division of the primitive cells) and of the carrier needed for energy transduction. It is suggested that the most primitive exploitable energy source was the donation of 2H++2e at the external face of the primitive cell. The electrons were transferred (by metal impurities) to internal sinks of organic material, thus creating, via a deficit, a protonmotive force that could drive both the active transport of phosphate and high-energy-bond formation.This model implies that proton translocation in a closed-membrane system preceded photochemical or electron transport mechanisms and that chemically transferable metabolic energy was needed at a much earlier stage in the development of life than has usually been assumed. It provides a plausible mechanism whereby cell division of the earliest protocells could have been a spontaneous process powered by the internal development of phospholipids. The stimulus for developing this evolutionary sequence was the realization that cellular life was essential if Darwinian survival of the fittest was to direct evolution toward adaptation to the external environment.  相似文献   

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