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1.
玫烟色拟青霉北京变种 总被引:1,自引:0,他引:1
1980年,自北京农家温室内,温室白粉虱(Trialeurodes vaporartorum)上分离到玫烟色拟青霉(Paecilomyces fumosoroseus)的若干菌株。用13号菌株的典型培养与本菌的原种做比较,发现在形态上与原种相似,但菌落色泽、生长速度及形成孢梗束的能力不同。故定名为玫烟色拟青霉北京变种(P.fumosoroseus var.beijingensis Fang et Q.T.Chen n.var.)。 相似文献
2.
Distribution of citrate utilization plasmids in Salmonella strains of bovine origin in Japan. 总被引:7,自引:0,他引:7
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Attempts to detect transferable citrate-utilizing (Cit) ability in enterobacterial strains were carried out by conjugation experiments. Of 318 strains of Salmonella typhimurium and 1 strain of Salmonella bredeney isolated from cattle in Japan from 1970 to 1979, 107 (33.5%) strains contained transferable Cit characters. Most of the strains transferred the Cit characters to recipient Escherichia coli more efficiently at 28 degrees C than at 37 degrees C, indicating that their transfer of the Cit character is thermosensitive. Transferred Cit characters were found in association with drug resistance markers such as ampicillin, chloramphenicol, kanamycin, streptomycin, sulfonamides, and tetracycline or with mercury resistance, but Cit plasmids conferring Cit ability alone were also obtained. Of 221 conjugative Cit plasmids tested for fertility inhibition (Fi), all but 2 were Fi- and exhibited thermosensitive transfer; 2 Cit plasmids showing the Fi+ character were also isolated from 2 S. typhimurium strains. No transferable Cit character was detected from strains of Proteus, Serratia, Klebsiella, Enterobacter, and Citrobacter spp. isolated from humans or cows in the present study. The utilization of tricarboxylic acids by strains with plasmid-borne Cit ability was examined, and two different patterns of utilization were found in the Cit+ E. coli transconjugants. 相似文献
3.
Z A Arkad'eva N F Piskunkova M N Pimenova 《Nauchnye doklady vysshe? shkoly. Biologicheskie nauki》1984,(8):86-88
After 20 years storage under the lyophylized condition 6 strains of Pseudomonas aeruginosa, P. fluorescens and P. putida retained all characters investigated. After storage under sterile vaseline oil for 10 years strains P. aeruginosa and P. putida lost one character, strains P. fluorescens lost 10-13 characters. 相似文献
4.
Lysogenization of nonlysogenic strains of Staphylococcus aureus was performed with two different bacteriophages, LS1 and LS2, that were unable to plaque on any of the strains of S. aureus tested. Infection of recipient strains was achieved when protoplasts were inoculated with LS1 or LS2 or when bacterial cultures were simultaneously inoculated with a virulent phage together with LS1 or LS2. Lysogenization was demonstrated by changes in phenotypic characters of the host strain and by liberation of bacteriophages from the modified strains as shown by electron microscopic examination. The lysogenic strains differed from the host strains by the following characters: they were coagulase, deoxyribonuclease, and lipase negative; they were untypable by the basic set of phages; they did not ferment mannitol under anaerobic conditions; and they produced only l-(+)-lactic acid by glucose fermentation. Their cell walls contained less glycine and concomitantly more serine than those of the host strains. Furthermore, they were devoid of protein A. Conversely, some antigenic factors as well as the presence of ribitol in the cell wall teichoic acid, indicated a parental relationship between the host strains and the derived lysogenic ones. Phages LS1 and LS2 could be excluded from the lysogenic strains by invading phages, and the revertant nonlysogenic strains recovered all of the characteristics of the initial host strains. It was thus concluded that the phenomenon described was due to lysogenic conversion. The origin of phages LS1 and LS2 is discussed. 相似文献
5.
Eleven Vibrio isolates invading the hemolymph of live and moribund oysters (Crassostrea gigas) collected in the field and from a hatchery in France, were characterized by a polyphasic approach. Phylogenetic analysis of 16S rRNA, gyrB and toxR genes indicated high homogeneity between these strains and the Vibrio aestuarianus type strain (ATCC35048(T)), and confirmed previous 16S rRNA analysis. In contrast, DNA:DNA hybridization was from 61% to 100%, while phenotypic characters and virulence tests showed a large diversity between the strains. Nevertheless, several common characters allowed the isolates to be distinguished from the reference strain. On the basis of several distinct phenotypic characteristics, it is proposed to establish two subspecies within the V. aestuarianus spp. group, V. aestuarianus subsp. aestuarianus [D. Tison, R. Seidler, Vibrio aestuarianus: a new species from estuarine waters and shellfish, Int. J. Syst. Bacteriol. (1983) 699-702] and V. aestuarianus subsp. francensis for these French isolates. The characters that differentiate the new strains from V. aestuarianus subsp. aestuarianus(T) are virulence (positive for 63% of the isolates) and 12:0 fatty acid content. The colonies were smaller and uncoloured, whereas no growth occurred at 35 degrees C or on TCBS, and the strains did not utilize several substrates, including L-serine, alpha-cyclodextrin, D-mannitol, alpha-glycyl-L-aspartic acid, L-threonine and glucose-1-phosphate. 相似文献
6.
A total of 176 Aeromonas strains representing all currently characterized genospecies were tested for 329 biochemical characters. Overall similarities of all strains were determined by numerical taxonomic techniques, the UPGMA algorithm and the SSM and the SJ coefficients as measures of similarity. Sixteen clusters (two or more strains) and seven unclustered strains were recovered at the 93.5% similarity level (SSM). Genospecies 1, 4, 5, 6, 7, 9, 12 and 13 were largely represented by single phena, whereas strains of genospecies 2 and 3 were found in closely-related phena. Strains belonging to genospecies 8 formed two distinct biotypes. Strains belonging to genospecies 11 formed a subcluster within a cluster representing different genospecies. In general, similar groupings were obtained with the Jaccard coefficient at a similarity level of 80.0% (SJ) with minor changes in the definition of clusters. The phenetic data showed good correlation with the taxa defined by DNA/DNA hybridization and those obtained by multilocus enzyme analysis. For all genospecies (independent from cluster assignment) 30 diagnostic characters were selected to construct a matrix for probabilistic identification. The correct identification rate of the matrix was 71.51% taking a Willcox probability greater than 0.99, and 83.7% taking a Willcox probability greater than 0.9 as identification threshold levels. 相似文献
7.
H. Albert Barker 《Archives of microbiology》1939,10(1-4):376-384
Summary A simple method has been developed to test the ability of anaerobes to ferment glutamic acid. This has been applied to a systematic study of seventeen strains of anaerobic spore-formers isolated from soil with the aid of enrichment cultures containing glutamic acid as the main source of carbon and energy. The twelve glutamic acid fermenting strains were found to be similar in their morphological and physiological characters except with respect to the utilization of glucose and pyruvate (with one strain also lactose, mannitol and salicin). These organisms are identified with two previously described species, Cl. cochlearium and Cl. tetanomorphum. The five glutamic acid negative strains differ distinctly from the positive strains also with respect to other characters. The ability to ferment glutamic acid therefore appears to be of taxonimic value. 相似文献
8.
Three isolated strains from human feces were characterized by biochemical tests and 16S rDNA analysis. Phylogenetic analysis revealed that these isolated strains were members of the Clostridium subphylum of gram-positive bacteria. The phenotypic characters resembled those of the genus Eubacterium, but these strains were shown to be phylogenetically distant from the type species of the genus, Eubacterium limosum. The strains showed a specific phylogenetic association with Holdemania filiformis and Erysipelothrix rhusiopathiae. Based on a 16S rDNA sequence divergence of greater than 12% with H. filiformis and E. rhusiopathiae, a new genus, Solobacterium, is proposed for three strains, with one species, Solobacterium moorei. The type strain of Solobacterium moorei is JCM 10645T. 相似文献
9.
Microbial metabolism of quinoline and related compounds. IV. Degradation of isoquinoline by Alcaligenes faecalis Pa and Pseudomonas diminuta 7 总被引:1,自引:0,他引:1
From sewage and soil isoquinoline-degrading organisms were enriched. Two strains could be isolated which were able to utilize isoquinoline as sole carbon source. The bacteria were tentatively identified as Alcaligenes faecalis and Pseudomonas diminuta with respect to their morphological and physiological characters. When growing on isoquinoline both strains excrete a metabolite into the medium which was identified as 1-oxo-1,2-dihydroisoquinoline. Alcaligenes faecalis was cultivated in continuous culture on 1-oxo-1,2-dihydroisoquinoline to improve growth on isoquinoline and degradative activity. 相似文献
10.
Isaka M Sappan M Jennifer Luangsa-Ard J Hywel-Jones NL Mongkolsamrit S Chunhametha S 《Fungal biology》2011,115(4-5):401-405
The insect pathogens in the genus Torrubiella s. lat. were recently divided into new genera based on molecular phylogenetic characters. Isolates collected at various locations in Thailand, were tested for their productivity of a hopane-type triterpene, zeorin (6α,22-dihydroxyhopane), when cultured in potato dextrose broth under static conditions. Among the 49 strains of Torrubiella s. lat. species, Conoideocrella luteorostrata (ten strains) and C. tenuis (seven strains), all collected on scale insects (Hemiptera), produced zeorin, whereas another six strains of Orbiocrella petchii (which was recently removed from Torrubiella) failed in the detection of this secondary metabolite. All other Torrubiella s. lat. (26 strains), collected on other insect hosts including leafhoppers (eight strains), Lepidoptera (one strain), and spiders (17 strains), produced no detectable zeorin. Paecilomyces cinnamomeus (nine strains), the anamorph of C. luteorostrata, also produced zeorin. These results correspond with the recent taxonomic reclassification based on multigene phylogeny. 相似文献
11.
在木耳栽培种质资源农艺性状调查的基础上,应用数量分类学中的Q型聚类分析法对20个木耳菌株进行分类研究,并对14个农艺性状进行R型聚类分析和主成分分析。结果表明:Q型聚类将20个木耳菌株在欧氏距离6.29处依据子实体朵型性状分为簇生型菌株和菊花型菌株两大类群,菊花型类群在欧式距离4.79处依据生育期性状的原基发生类型划分为分散型和集中型两个亚群;R型聚类表明菌丝体性状(1个)、生育期性状(2个)、子实体性状(8个)等11个农艺性状间相关性较强;主成分分析中,发现子实体背面皱褶、耳片数、原基发生时间、子实体朵型、干耳背面颜色等5个性状是14个农艺性状的第1主成分,贡献率高达62.26%,把第1主成分命名为朵型-生育期构成因子,作为种质评价的指标。 相似文献
12.
Three different strains of green hydra were isolated in successive years from a single site in the River Frome, Bristol, England. The strains resembled each other in important taxonomic characters, and were identified as Hydra viridissima by their possession of smooth-walled single-chambered embryothecas, but were smaller, possessed smaller nematocysts and produced fewer eggs per individual than the Western European holotype. It is possible that English green hydra represent a geographical subspecies.
The three strains could be distinguished from each other by differences in rates of bud production and in characters associated with their symbiotic algae. These differences are considered varietal, and it is suggested that H. viridissima is a polytypic species. The possible origins of these variations and their significance is discussed. 相似文献
The three strains could be distinguished from each other by differences in rates of bud production and in characters associated with their symbiotic algae. These differences are considered varietal, and it is suggested that H. viridissima is a polytypic species. The possible origins of these variations and their significance is discussed. 相似文献
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15.
Numerical classification of species of Vibrio and related genera 总被引:10,自引:0,他引:10
T. N. Bryant § J. V. Lee † P. A. West ‡| R. R. Colwell ‡ 《Journal of applied microbiology》1986,61(5):437-467
Data from 1091 strains of the family Vibrionaceae collected in five different studies have been merged into a single data matrix and analysed in a taxonomic study. A set of 142 characters was selected to compare these data. Seventy-nine characters were common to all studies, but data for the other 63 characters were incomplete. Cultures of 90 strains, examined in more than one of the original studies, were used to estimate test error and inter-study variability. The data from these replicate strains also allowed the problem of merging data from different studies to be assessed. Taxonomic resemblance was estimated on the basis of 111 characters using the SSM coefficient and UPGMA clustering. A taxonomic analysis based on 999 strains, which included most of the major species of the family Vibrionaceae, gave 59 clusters and 44 unclustered strains. A table of properties of these phenons was produced. The results showed that data obtained from studies carried out at different times and in different locations, but using standard techniques, could be combined and used to provide useful taxonomic information. 相似文献
16.
GENETIC ANALYSIS OF DEVELOPMENTAL MECHANISMS IN HYDRA I. SEXUAL REPRODUCTION OF HYDRA MAGNIPAPILLATA AND ISOLATION OF MUTANTS 总被引:1,自引:0,他引:1
Hydra magnipapillata strains collected from various localities in Japan were induced to reproduce sexually.
From the survival data of the progeny, it was calculated that H. magnipapillata contained an average of between 3.5 and 4.0 lethal equivalent units of recessive deleterious genes per gamate (between 7.0 and 8.0 per animal).
Various types of developmental mutants were found among the offspring of crosses made between strains isolated from the same ponds. The mutant types isolated included mini strains, maxi strains, multi-headed strains, nematocyst-deficient strains, regeneration-deficient strains and male sterile strains. The characters of these strains were stably transmissible to the successive progeny produced by budding. These strains therefore were propagated by budding and maintained as clonal lines to be used later for developmental studies. 相似文献
From the survival data of the progeny, it was calculated that H. magnipapillata contained an average of between 3.5 and 4.0 lethal equivalent units of recessive deleterious genes per gamate (between 7.0 and 8.0 per animal).
Various types of developmental mutants were found among the offspring of crosses made between strains isolated from the same ponds. The mutant types isolated included mini strains, maxi strains, multi-headed strains, nematocyst-deficient strains, regeneration-deficient strains and male sterile strains. The characters of these strains were stably transmissible to the successive progeny produced by budding. These strains therefore were propagated by budding and maintained as clonal lines to be used later for developmental studies. 相似文献
17.
Cloning in Streptococcus lactis of plasmid-mediated UV resistance and effect on prophage stability. 总被引:5,自引:4,他引:1
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Plasmid pIL7 (33 kilobases) from Streptococcus lactis enhances UV resistance and prophage stability. A 5.4-kilobase pIL7 fragment carrying genes coding for both characters was cloned into S. lactis, using plasmid pHV1301 as the cloning vector. The recombinant plasmid was subsequently transferred to three other S. lactis strains by transformation or protoplast fusion. Cloned genes were expressed in all tested strains. 相似文献
18.
One hundred and twenty-two food, clinical, and veterinary strains of Listeria monocytogenes were examined for the presence of plasmids. Twenty-five (20%) contained plasmids, which varied from 1.3 to 66 MDa in size. Of 10 strains of other Listeria species (L. innocua, L. ivanovii, L. welshimeri, L. seeligeri, L. grayi, and L. murrayi) examined, seven (70%) contained plasmids, varying from 38 to 53 MDa. No strains with multiple plasmids were found. Plasmids of identical size were isolated from related strains in some, although not all, cases. The presence of a plasmid in a strain was not related to phenotypic characters of known extrachromosomal inheritance. 相似文献
19.
Gobiocypris rarus, a small, native cyprinid fish, is currently widely used in research on fish pathology, genetics, toxicology, embryology, and physiology in China. To develop this species as a model laboratory animal, inbred strains have been successfully created. In this study, to explore a method to discriminate inbred strains and evaluate inbreeding effects, morphological variation among three wild populations and three inbred stocks of G. rarus was investigated by the multivariate analysis of eight meristic and 30 morphometric characters. Tiny intraspecific variations in meristic characters were found, but these were not effective for population distinction. Stepwise discriminant analysis and cluster analysis of conventional measures and truss network data showed considerable divergence among populations, especially between wild populations and inbred stocks. The average discriminant accuracy for all populations was 82.1% based on conventional measures and 86.4% based on truss data, whereas the discriminant accuracy for inbred strains was much higher. These results suggested that multivariate analyses of morphometric characters are an effective method for discriminating inbred strains of G. rarus. Morphological differences between wild populations and inbred strains appear to result from both genetic differences and environmental factors. Thirteen characters, extracted from stepwise discriminant analysis, played important roles in morphological differentiation. These characters were mainly measures related to body depth and head size. 相似文献
20.
用19株抗鸡新城疫病毒(NDV)单克隆抗体(简称单抗)测定与14个NDV国际参考株和16个NDV国内分离株的反应性,将毒株分为a~h 8个群。该组单抗能较精细地测出流行病学上不同的毒株间的抗原变异,毒株分群显示了抗原变异与流行病学特征的相关性。 相似文献