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1.
Extracts from the fruits of Capsicum frutescens L. were tested for their clastogenicity using the mouse-bone-marrow micronucleus (mouse-MN) assay. Results of the mouse-MN, an in vivo method, indicated that the isolate CF-1 is clastogenic at the maximum tolerated dose of 1.22 mg/kg mouse. Statistical analysis using the Wilcoxon two-sample test showed that the null hypothesis, μtetracycline = μCF-1, is acceptable at 0.05 and 0.01 degrees of significance. Hence, the clastogenicity of CF-1 is statistically similar to that of tetracycline, a known clastogen, at the 5% and 1% levels of significance.  相似文献   

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We describe the polyphasic characterization of four Vibrio isolates which formed a tight AFLP group in a former study. The group was closely related to V. cyclitrophicus, V. lentus and V. splendidus (98.2-98.9% similarity) on the basis of the 16S rDNA sequence analysis, but by DNA-DNA hybridisation experiments it had at maximum 61% DNA similarity towards V. splendidus. Thus, we propose that the isolates represent a new Vibrio species i.e. V. tasmaniensis (LMG 20012T; EMBL under the accession numbers AJ316192; mol% G+C of DNA of the type strain is 44.7). Useful phenotypical features for discrimination of V. tasmaniensis from other Vibrio species include gelatinase and beta-galactosidase activity, fatty acid composition (particularly 14:0), utilisation and fermentation of different compounds (e.g. sucrose, melibiose and D-galactose) as sole carbon source.  相似文献   

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A novel plant-associated obligate methylotrophic bacterium, designated strain Ca-68T, was isolated from the rhizosphere soil of field-grown red pepper from India. The isolates are strictly aerobic, Gram negative, motile rods multiplying by binary fission and formaldehyde is assimilated via the ribulose monophosphate pathway. A comparative 16S rRNA gene sequence-based phylogenetic analysis placed the strain in a clade with the species Methylobacillus flagellatus, Methylobacillus glycogens and Methylobacillus pratensis, with which it showed pairwise similarity of 97.8, 97.4 and 96.2 %, respectively. The major fatty acids are C16:0, C10:0 3OH and C16:1 ω7c. The G+C content of the genomic DNA is 59.7 mol%. The major ubiquinone is Q-8. Dominant phospholipids are phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Based on 16S rRNA gene sequence analysis and DNA–DNA relatedness (14–19 %) with type strains of the genus Methylobacillus, the novel isolate was classified as a new species of this genus and named Methylobacillus rhizosphaerae Ca-68T (=KCTC 22383T = NCIMB 14472T).  相似文献   

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An aerobic, non-motile, Gram-stain positive actinomycete, designated strain CA3R110T, was isolated from the surface-sterilised root of Coffea arabica L. collected from Lampang Province, Thailand. 16S rRNA gene sequence analysis indicated that strain CA3R110T was a member of the genus Streptomyces and showed the closest similarities to Streptomyces buecherae AC541T (99.2%), followed by Streptomyces rapamycinicus NRRL B-5491T (99.1%), Streptomyces luteoverticillatus NBRC 3840T (99.1%), Streptomyces coerulescens NBRC 12758T (99.1%), and Streptomyces iranensis HM 35T (99.0%). Strain CA3R110T contained LL-diaminopimelic acid in cell peptidoglycan, MK-9(H6), and MK-9(H8) as major menaquinone, iso-C16:0, iso-C15:0, C16:0 as major fatty acids. Diphosphatidylglycerol, phosphatidylethanolamine, hydroxy-phosphatidylethanolamine, phosphatidylglycerol, phosphatidylinositol, phosphatidylinositolmannoside were detected in the cell. The chemotaxonomic characteristics possessed the typical properties of the genus Streptomyces. A low digital DNA–DNA hybridization (<?55.7%) and average nucleotide identity-blast (ANIb) (<?92.2%) values revealed that strain CA3R110T could be distinguished from any known Streptomyces species. With the differences in phenotypic and genotypic data, strain CA3R110T represents a novel species of genus Streptomyces, for which the name Streptomyces endocoffeicus sp. nov. is proposed. The type strain is CA3R110T (=?TBRC 11245T?=?NBRC 114296T).

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Summary Ethyl methane sulphonate (EMS) is a potential mutagen to induce lincomycin resistance in Capsicum annuum. Mutagenized cotyledons were cultured on shoot regenerating medium containing lincomycin (100 mgl−1). Approximately 14% of regenerated shoots were chlorophyll deficient and about 4% of regenerated shoots were green from mutaganized cotyledons. The regenerated green plants were resistant to lincomycin but sensitive to chloramphenicol, kanamycin, spectinomycin, and streptomycin. Reciprocal crosses were made between resistant and sensitive plants. Inheritance of lincomycin resistance was transmitted as a non-Mendelian trait. Lincomycin resistance is a first selectable and maternally inherited organelle encoded genetic marker described in chili pepper. Such mutants should be useful in designing biochemical selection schemes to recover somatic hybrids and cybrids.  相似文献   

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A new species of Penicillium Link ex Fries is described and illustrated. It was recovered from sunflower seed (Helianthus annuus L.) in Yugoslavia. It clearly differs from all species of the genus described so far and is, therefore, proposed as a new taxon: Penicillium yugoslavicum sp. nov.  相似文献   

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A Gram-stain positive, filamentous bacterial strain, designated strain NEAU-TWSJ13T, was isolated from the rhizosphere of a marigold (Tagetes erecta L.) plant collected in Heilongjiang Province, northeast China, and characterized using a polyphasic approach. The strain was observed to form abundant aerial hyphae differentiated into spherical sporangia. 16S rRNA gene sequence similarity studies showed that strain NEAU-TWSJ13T belongs to the genus Streptosporangium, being most closely related to Streptosporangium fragile DSM 43847T (98.6 %). Phylogenetic analysis of the 16S rRNA gene sequence indicated that it formed a phyletic line with S. fragile DSM 43847T, Streptosporangium jomthongense NBRC 110047T (98.4 % 16S rRNA gene similarity) and Streptosporangium violaceochromogenes DSM 43849T (97.6 % 16S rRNA gene similarity). A combination of DNA–DNA hybridization results and some phenotypic characteristics indicated that strain NEAU-TWSJ13T can be distinguished from S. fragile DSM 43847T and S. jomthongense NBRC 110047T. Moreover, strain NEAU-TWSJ13T can also be differentiated from S. violaceochromogenes DSM 43849T and other Streptosporangium species showing high 16S rRNA gene sequence similarity (>98.0 %) by morphological and physiological characteristics. Therefore, it is proposed that strain NEAU-TWSJ13T represents a novel species of the genus Streptosporangium, for which the name Streptosporangium subfuscum sp. nov. is proposed. The type strain is NEAU-TWSJ13T ( = CGMCC 4.7146T = DSM = 46724T).  相似文献   

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Three pink-colored yeast strains 3-1-3, 10-3-3 and 19-3-3 were isolated from xylem of surface-sterilized twigs of Pinus tabulaeformis collected from Dongling Mountain, Beijing, in different seasons. These strains were identified as Rhodotorula minuta (Saito) F.C. Harrison by conventional taxonomic characterization. However, molecular phylogenetic analysis based on internal transcribed spacer region (including 5.8S rDNA) and large-subunit rDNA D1/D2 domain sequences indicated that they represent a novel basidiomycetous yeast species, for which Rhodotorula pinicola is proposed (type strain: AS 2.2193(T)=CBS 9130(T)). The new species was most closely related to Rhodotorula laryngis Reiers?l in the R. minuta complex.  相似文献   

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Mycoplasmas isolated from the throats of lions were shown to belong to three serotypes, all of which were serologically distinct from the previously recognized Mycoplasma and Acholeplasma spp. Eight mycoplasma colonies were cloned, including one from a leopard (strain LP), and were examined in detail for morphology, growth, and biochemical characteristics. The strains had the following properties: guanine-plus-cytosine contents of 37 mol% (strain LXT [T = type strain]), 28 mol% (strain LL2T), and 27 mol% (strain 3L2T) and a requirement for sterol. Strain 3L2T metabolized glucose, which was not metabolized by strains LXT and LL2T. Arginine and urea were not hydrolyzed. Strain LX (= NCTC 11724) is the type strain of a new species, Mycoplasma simbae; strain LL2 (= NCTC 11725) is the type strain of a second new species, Mycoplasma leopharyngis; and strain 3L2 (= NCTC 11726) is the type strain of a third new species, Mycoplasma leocaptivus.  相似文献   

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Morphological and chemotaxonomic characterization of actinomycete strain S582 isolated from the gut of a termite (Speculitermes sp.) in Pathum Thani Province, Thailand, clearly demonstrated that this strain is a member of the genus Saccharopolyspora. 16S rDNA sequence analysis for the strain supported the assignment of the strain to the genus Saccharopolyspora. The similarity value of sequences between this strain and the closely related species Saccharopolyspora endophytica was 99.5%. The DNA G+C content was 70.2 mol%. DNA-DNA hybridization results (53.3%) and some physiological and biochemical properties indicated that strain S582(T) was distinguished from the phylogenetically closest relatives. Based on these genotypic and phenotypic data, strain S582(T) should be a new species in the genus Saccharopolyspora and the name Saccharopolyspora pathumthaniensis sp. nov. is proposed for the strain. The type strain is S582(T) (=NBRC 104112(T) =BCC 28624(T)).  相似文献   

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In 1979 and 1980, more than 400 harbor seals (Phoca vitulina) along the New England coast of the United States died of epizootic pneumonia that was attributed to an influenza virus. Six mycoplasma isolates that were recovered from the respiratory tracts of affected seals were investigated and were found to be serologically identical and distinct from previously described species. These isolates required serum for growth, did not possess a cell wall, and did not hydrolyze urea. Arginine was hydrolyzed, glucose was not fermented, film and spots were observed on horse serum agar, phosphatase was produced, tetrazolium was not reduced, and serum and casein were not digested. The guanine-plus-cytosine content of the DNA was 27.8 mol%. We propose the name Mycoplasma phocidae for these isolates. The type strain of M. phocidae is strain 105 (= ATCC 33657).  相似文献   

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Three Gram-positive, anaerobic, pleomorphic strains (PG10(T), PG18 and PG22), were selected among five strains isolated from pig slurries while searching for host specific bifidobacteria to track the source of fecal pollution in water. Analysis of the 16S rRNA gene sequence showed a maximum identity of 94% to various species of the family Bifidobacteriaceae. However, phylogenetic analyses of 16S rRNA and HSP60 gene sequences revealed a closer relationship of these strains to members of the recently described Aeriscardovia, Parascardovia and Scardovia genera, than to other Bifidobacterium species. The names Neoscardovia gen. nov. and Neoscardovia arbecensis sp. nov. are proposed for a new genus and for the first species belonging to this genus, respectively, and for which PG10(T) (CECT 8111(T), DSM 25737(T)) was designated as the type strain. This new species should be placed in the Bifidobacteriaceae family within the class Actinobacteria, with Aeriscardovia aeriphila being the closest relative. The prevailing cellular fatty acids were C(16:0) and C(18:1)ω9c, and the major polar lipids consisted of a variety of glycolipids, diphosphatidyl glycerol, two unidentified phospholipids, and phosphatidyl glycerol. The peptidoglycan structure was A1γmeso-Dpm-direct. The GenBank accession numbers for the 16S rRNA gene and HSP60 gene sequences of strains PG10(T), PG18 and PG22 are JF519691, JF519693, JQ767128 and JQ767130, JQ767131, JQ767133, respectively.  相似文献   

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Morphological, biochemical, and molecular genetic studies were performed on an unknown anaerobic, catalase-negative, non-spore-forming, rod-shaped bacterium isolated from dog feces. The unknown bacterium was tentatively identified as a Eubacterium species, based on cellular morphological and biochemical tests. 16S rRNA gene sequencing studies, however, revealed that it was phylogenetically distant from Eubacterium limosum, the type species of the genus Eubacterium. Phylogenetically, the unknown species forms a hitherto unknown sub-line proximal to the base of a cluster of organisms (designated rRNA cluster XVI), which includes Clostridium innocuum, Streptococcus pleomorphus, and some Eubacterium species. Based on both phenotypic and phylogenetic criteria, it is proposed that the unknown bacterium be classified as a new genus and species, Allobaculum stercoricanis. Using a specific rRNA-targeted probe designed to identify Allobaculum stercoricanis, in situ hybridisation showed this novel species represents a significant organism in canine feces comprising between 0.1% and 3.7% of total cells stained with DAPI (21 dog fecal samples). The type strain of Allobaculum stercoricanis is DSM 13633(T)=CCUG 45212(T).  相似文献   

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