共查询到17条相似文献,搜索用时 78 毫秒
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对中国普通微生物菌种保藏中心(CGMCC)保藏的云南原小单孢菌(Promicromonospora yunnanensis)AS4.1333进行的多相分类研究表明,菌株AS4.1333与纤维化纤维菌(Cellulosimicrobium cellulans)DSM43879T关系密切,它们的16S rRNA基因序列相似性为99.6%,DNA同源性为89.3%。胞壁组分、枝菌酸、甲基萘醌、磷酸类脂和DNAG Cmol%测定等化学分类结果支持了上述结论。在形态和生理生化特性上,菌株AS4.1333与CellulosimicrobiumcellulansDSM43879T之间也表现出非常相似的性状。根据系统发育分析、化学分类、形态和生理生化特性、DNA同源性测定等研究结果,对菌株AS4.1333的分类地位做了修正,将其从原小单孢菌属中排除,认为菌株AS4.1333与Cellulosimicrobium cellulansDSM43879T是同一个种,建议将菌株AS4.1333由云南原小单孢菌(Promicromonosporayunnanensis)转入纤维化纤维菌(Cellulosimicrobium cellulans)。 相似文献
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糖多孢菌属的多相分类 总被引:1,自引:0,他引:1
在糖多孢菌属的分类学研究中,最初是根据形态特征、培养特征及生理生化特征等表观分类学指征进行研究。随着“多相分类”方法的广泛应用,化学分类和分子分类在糖多孢菌属的分类学研究中起到越来越重要的作用。糖多孢菌是寻找新的生物活性物质的重要菌源,某些种能产生重要的生物活性物质,如抗生素、酶类、维生素、藻类促生长因子、纤维素降解促进因子、免疫抑制剂等。 相似文献
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从西藏念青唐古拉山卡拉山支脉的土样中分离到40株放线菌,对其中的13株菌进行了多相分类。形态、培养特征和系统发育结果表明,所有菌株均属于链霉菌属。从系统发育结果看,840018、850003和Z851023各处于一个独立的分支,分别与Streptomyces rishiriensis、Streptomyces cyanoalbus和Streptomyces albus subsp.albus的相似性达到99%。菌株Z851010、Z851004、850011和850070聚成一个小群,它们之间的相似性达到95%,与Streptomyces sp.YIM26的相似性达到98%;Z851013和Z851024聚成小群,它们之间的相似性达到100%,它们有可能是同一种菌株;850008和Z851020聚成小群,它们的相似性达到95%;Z850007和850040聚成小群,与已知菌种的相似性只有96%,有可能是新的分类单元。 相似文献
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采用数值分类,全细胞可溶性蛋白电泳分析,DNA,G+Cmol%和DNA相关性的测定以及16SrDNAPCR-RFL分析等多相分类技术对来源于不同地区的16种寄主的胡枝子根瘤菌进行了系统的分类研究,数值分类的结果表明,在67%的相似性水平上,全部供试菌可以为快生型根瘤菌和慢性型根瘤菌两大群,在80%的相似性水平上又可分为两个亚群。在此基础上,对各亚群的胡枝子根瘤菌进行了DNA相关性的测定,以进一步证 相似文献
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根瘤菌多样性和系统发育研究的多相分类体系及其进展 总被引:4,自引:0,他引:4
近年来对新的根瘤菌资源的不断发掘及现代分子生物学技术的发展和应用使根瘤菌分类研究有了突破性进展。多相分类通过综合获取信息,多种方法相互印证、互为补充,推进了根瘤菌的表型、遗传型和系统发育三方面的发展,从而较全面地反映根瘤菌的生物多样性特征,是根瘤菌多样性研究工作中常常采用的技术手段。文中主要阐述了根瘤菌多相分类体系中的主要方法及现代根瘤菌系统发育地位的研究和进展。 相似文献
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三株沙漠放线菌XJSS-21、XJSS-39和XJSS-58的多相分类及特性研究 总被引:1,自引:0,他引:1
从新疆吐鲁番鄯善县典型沙漠地区中采集的样品中分离获得3株放线菌菌株XJSS-21、XJSS-39和XJSS-58, 对其形态特征、生理生化特性、反硝化能力、细胞壁化学组分以及16S rRNA基因序列等进行了多相分类研究, 发现3种沙漠放线菌均能产生纤维素酶, 淀粉酶和蛋白酶, 且菌株XJSS-21具有很强的反硝化能力, XJSS-58属于轻度耐盐菌。初步确定XJSS-21可能属于Streptomyces humidus subsp. antitumoris, XJSS-39可能属于Nocardiopsis dassonvillei, XJSS-58可能属于Streptomyces mutabilis。 相似文献
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Acetic acid bacteria (AAB) are obligately aerobic bacteria within the family Acetobacteraceae, widespread in sugary, acidic and alcoholic niches. They are known for their ability to partially oxidise a variety of carbohydrates and to release the corresponding metabolites (aldehydes, ketones and organic acids) into the media. Since a long time they are used to perform specific oxidation reactions through processes called “oxidative fermentations”, especially in vinegar production. In the last decades physiology of AAB have been widely studied because of their role in food production, where they act as beneficial or spoiling organisms, and in biotechnological industry, where their oxidation machinery is exploited to produce a number of compounds such as l-ascorbic acid, dihydroxyacetone, gluconic acid and cellulose. The present review aims to provide an overview of AAB physiology focusing carbon sources oxidation and main products of their metabolism. 相似文献
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The acetic acid bacteria (AAB) have important roles in food and beverage production, as well as in the bioproduction of industrial chemicals. In recent years, there have been major advances in understanding their taxonomy, molecular biology, and physiology, and in methods for their isolation and identification. AAB are obligate aerobes that oxidize sugars, sugar alcohols, and ethanol with the production of acetic acid as the major end product. This special type of metabolism differentiates them from all other bacteria. Recently, the AAB taxonomy has been strongly rearranged as new techniques using 16S rRNA sequence analysis have been introduced. Currently, the AAB are classified in ten genera in the family Acetobacteriaceae. AAB can not only play a positive role in the production of selected foods and beverages, but they can also spoil other foods and beverages. AAB occur in sugar- and alcohol-enriched environments. The difficulty of cultivation of AAB on semisolid media in the past resulted in poor knowledge of the species present in industrial processes. The first step of acetic acid production is the conversion of ethanol from a carbohydrate carried out by yeasts, and the second step is the oxidation of ethanol to acetic acid carried out by AAB. Vinegar is traditionally the product of acetous fermentation of natural alcoholic substrates. Depending on the substrate, vinegars can be classified as fruit, starch, or spirit substrate vinegars. Although a variety of bacteria can produce acetic acid, mostly members of Acetobacter, Gluconacetobacter, and Gluconobacter are used commercially. Industrial vinegar manufacturing processes fall into three main categories: slow processes, quick processes, and submerged processes. AAB also play an important role in cocoa production, which represents a significant means of income for some countries. Microbial cellulose, produced by AAB, possesses some excellent physical properties and has potential for many applications. Other products of biotransformations by AAB or their enzymes include 2-keto-L-gulonic acid, which is used for the production of vitamin C; D-tagatose, which is used as a bulking agent in food and a noncalorific sweetener; and shikimate, which is a key intermediate for a large number of antibiotics. Recently, for the first time, a pathogenic acetic acid bacterium was described, representing the newest and tenth genus of AAB. 相似文献
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Summary Three laboratory-scale water pipe systems were set up to study the effects of adding two levels of acetic acid (10 and 50
μg acetate eq-C l−1) on the bacterial regrowth in water pipes. The results of the water pipe test showed that nearly all carbon in the acetic
acid could be readily utilized by bacteria and resulted in an increase in biomass concentration. The maximum heterotrophic
plate counts in biofilm were equal to 3.5 × 104, 8.9 × 105 and 2.9 × 107 c.f.u. cm−2 while the maximum heterotrophic plate counts of free bacteria were equal to 1.2 × 103, 5.0 × 103 and 6.8 × 104 c.f.u. ml−1 for the blank and with addition of 10 and 50 μg acetate eq-C l−1. These results showed that addition of acetic acid to drinking water has a positive effect on the assimilable organic carbon
content of drinking water and bacterial regrowth in the distribution system. This effect is enhanced with addition of high-level
acetic acid. Batch tests were also conducted using water samples collected from a Taiwanese drinking water distribution system.
The bacterial regrowth potentials of the blank were equal to 4.3 × 103, 1.5 × 104, 4.9 × 104 and 7.5 × 104 c.f.u. ml−1 for water samples collected from treatment plant effluent, commercial area, mixed area, and residential area, respectively.
These results showed that the biological stability of drinking water is the highest in treatment plant effluent, followed
by distributed water of the commercial area, distributed water of the mixed area, and then the distributed water of residential
area. 相似文献
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Syed G. Dastager Ashok Pandey Jae-Chan Lee Wen-Jun Li Chang-Jin Kim 《Current microbiology》2009,59(1):21-29
Aerobic, alkaliphilic to alkalitolerant and mesophilic bacteria were isolated and characterized from soil and sediment samples
collected from Bigeum Island, South Korea. The total numbers of microorganisms in the soil and sediment samples were found
to be 103–105 cfu/g and 102–107 cfu/g, respectively. A total of 163 isolates were isolated and subjected to further characterization on the basis of pH,
temperature and salt tolerance. Among the 163 isolates, 54 were selected based on their tolerance attributes to temperature,
pH and NaCl. Out of the 54 isolates, 27 were further selected based on their multiple tolerance ability and enzyme profile
and were subjected to 16S rRNA gene sequencing and phylogenetic analysis. The latter indicated that most of the Bigeum Island
isolates were related to the phylum Actinobacteria. The phylogenetic tree based on 16S rRNA gene sequences placed the 27 isolates into 9 different major bacterial genera, each
genus comprising pure cultures that shared ≤97% sequence identity and 18 putative novel species. Most of the strains were
alkalitolerant and mesophilic, and produced biotechnologically important enzymes at alkaline pH. 相似文献