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1.
Cytopathogenic agents have been isolated in a search for viruses in the feces of apparently healthy mice (an inbred strain DK1) by using mouse kidney tissue culture. This report is concerned with the identification of strain K87, one of our isolates, as an adenovirus. Strain K87 was cytopathogenic to mouse kidney tissue culture but not to monkey kidney tissue culture, FL, and HeLa cells. The K87 strain was not able to grow in bacterial media and was resistant to penicillin, streptomycin and tetracycline. 5-Bromodeoxyuridine inhibited the occurrence of the cytopathogenic effect and virus replication in infected cells and the inhibitory effect was reversed by thymidine, suggesting that the virus contains DNA. Strain K87 was resistant to ethyl-ether but did not have the property of cationic stabilization to thermal inactivation. Electronmicroscopic observations of thin-sections of the K87-infected cells showed virus particles in crystalline array in the nuclei. Each virus particle was an icosahedron of about 75 mμ in diameter composed of 252 capsomeres, and without an envelope. By the complement fixation test, K87 was related serologically to a human adenovirus. All the facts indicate that strain K87 belongs to the adenovirus group. The problem whether strain K87 may be a new mouse adenovirus with pathogenicity and antigenicity different from that of a mouse adenovirus previously reported by Hartley and Rowe is discussed.  相似文献   

2.
Release of Adenovirus Messenger RNA from Isolated Nuclei   总被引:12,自引:0,他引:12  
Nuclei from adenovirus infected cells release labelled viral RNA as ribo-nucleoprotein when incubated with ATP and an ATP generating system.  相似文献   

3.
本文研究了人粪便中分离的噬菌蛭弧菌的生物学特性,测定了它们的生长曲线,并利用微孔滤膜过滤和机械振荡的方法,研究了它们的吸附和穿入动力学,发现链霉素、庆大霉素和卡那霉素能抑制蛭弧菌的吸附;青霉素不影响蛭弧菌的吸附和穿入,但抑制蛭弧菌在宿主内的生长过程。从人粪中分出的噬菌蛭弧菌不仅能裂解大部分需氧的革兰氏阴性菌,而且在微氧条件下也能裂解厌氧菌中的二株脆弱拟杆菌。我们发现一株人粪便中分出的噬菌蛭弧菌能形成蛭弧菌囊体——它的休眠态,它对高热、紫外线照射和真空干燥的耐受力较相应的繁殖体强,看来它是蛭弧菌保持生命期限的一种方式。  相似文献   

4.
Ruth Faulkner  C. E. van Rooyen 《CMAJ》1962,87(21):1123-1125
Adenoviruses types 3 and 5 were isolated from the cerebrospinal fluid of two sick children. These agents were thought to be responsible for the neurological state of the children at the phase of illness when they were isolated. The possibility of mixed infections or of superimposed infections was considered since one was isolated following herpes zoster infection in the one child and the other following varicella. The role of adenoviruses as latent agents of potential pathogenicity is discussed.  相似文献   

5.
A new bacterial strain, designated as FF42T, was isolated from feces of domestic pigs—collected from Suwon, Korea—and was characterized to determine its taxonomic position. Strain FF42T was observed to be Gram negative, aerobic, non-spore forming, motile, and rod-shaped cells. Based on the phylogenetic and 16S rRNA sequence analyses, it was revealed that strain FF42T belonged to the genus Comamonas. The highest degree of sequence similarities was determined to be with Comamonas zonglianii BF-3T (96.3 %), Comamonas composti CC-YY287T (96.1 %), and Comamonas nitrativorans 23310T (95.9 %), while showing less than 95.6 % identity with the remaining Comamonas species. Growth of strain FF42T occurred between 25 and 40 °C (optimum, 28 °C) and at pH of 5-9 (optimum, pH 6.0). It grew in the presence of 0–3 % (w/v) NaCl while minimally tolerating at 3 % (w/v) NaCl. Biochemical and physiological tests revealed phenotypic differentiation of strain FF42T to other members of the genus Comamonas. The predominant quinone is ubiquinone (Q-8). The major cellular fatty acids were C10:0 3OH, C16:0, summed feature 3 (C16:1 ω7c/C16:1 ω6c), and summed feature 8 (C18:1 ω6c/C18:1 ω7c), all of which have previously been reported to occur in the species of the genus Comamonas. The G+C molar content for strain FF42T is 60.2 mol %. Based on phylogenetic and phenotypic analyses, strain FF42T (=KEMC 1002-058T=JCM 17561T) is clearly referred to be a novel species for the genus Comamonas, for which the name Comamonas faecalis sp. nov. is proposed.  相似文献   

6.
Lactobacillus mucosae LM1, isolated from stool samples of a healthy piglet, displays good in vitro mucin adhesion and antimicrobial activity against pathogenic bacteria. To elucidate its antimicrobial effects and to find its epithelial cell and mucin adhesion genes, the genomic sequence of L. mucosae LM1 was investigated.  相似文献   

7.
8.
The assimilation of sodium cyclamate (CHS-Na) by microorganisms was studied. Fifteen strains of cyclamate-assimilating bacteria were isolated from the feces of guinea pig excreting cyclohexylamine (CHA) in urine. The majority of the strain isolated seems to belong to the genera Pseudomonas and Corynebacterium. All strains were able to assimilate CHS-Na as a sole source of carbon and nitrogen, and accumulated clearly CHA in the culture medium. It was confirmed with the cell-free extract that the strains possessed the enzyme system which formed cyclohexanone (CHnone) from CHS-Na via CHA. It seems that the desulfation of CHS-Na to CHA is catalyzed by hydrolase, and that the deamination of CHA to CHnone is catalyzed by amine oxidase depending on oxygen.  相似文献   

9.
Coprophilous fungi inhabit herbivore feces, secreting enzymes to degrade the most recalcitrant parts of plant biomass that have resisted the digestive process. Consequently, the secretomes of coprophilous fungi have high potential to contain novel and efficient plant cell wall degrading enzymes of biotechnological interest. We have used one-dimensional and two-dimensional gel electrophoresis, matrix-assisted laser desorption ionization-time-of-flight tandem mass spectrometry (MALDI-TOF/TOF MS/MS), and quadrupole time-of-flight liquid chromatography-tandem mass spectrometry (Q-TOF LC-MS/MS) to identify proteins from the secretome of the coprophilous fungus Doratomyces stemonitis C8 (EU551185) isolated from koala feces. As the genome of D. stemonitis has not been sequenced, cross-species identification, de novo sequencing, and zymography formed an integral part of the analysis. A broad range of enzymes involved in the degradation of cellulose, hemicellulose, pectin, lignin, and protein were revealed, dominated by cellobiohydrolase of the glycosyl hydrolase family 7 and endo-1,4-β-xylanase of the glycosyl hydrolase family 10. A high degree of specialization for pectin degradation in the D. stemonitis C8 secretome distinguishes it from the secretomes of some other saprophytic fungi, such as the industrially exploited T. reesei. In the first proteomic analysis of the secretome of a coprophilous fungus reported to date, the identified enzymes provide valuable insight into how coprophilous fungi subsist on herbivore feces, and these findings hold potential for increasing the efficiency of plant biomass degradation in industrial processes such as biofuel production in the future.  相似文献   

10.
Vancomycin-resistant Enterococcus spp. (VRE) were isolated from sewage and chicken feces but not from other animal fecal sources (dog, cow, and pig) or from surface waters tested. VRE from hospital wastewater were resistant to ≥20 μg of vancomycin/ml and possessed the vanA gene. VRE from residential wastewater and chicken feces were resistant to 3 to 5 μg of vancomycin/ml and possessed the vanC gene.  相似文献   

11.
Twenty-four strains of anaerobic fusiform-shaped bacteria were isolated from the caecum of conventional mice. Ten of the isolates belonged to the genus Clostridium , nine to Fusobacterium and five to Bacteroides. The clostridia were put into eight biotypes on the basis of their ability to: hydrolyze mucin and esculin; produce indole and hydrogen; utilize pyruvate, and ferment arabinose, cellobiose, fructose, glucose, galactose, maltose, mannose and N-acetylglucosamine and on the acid end-products of such fermentations. The fusobacteria were assigned to six biotypes based on their ability to hydrolyze casein, mucin and starch, and to ferment arabinose, lactose, maltose and N-acetylglucosamine. Each of the bacteroides was deemed to be a separate biotype because of the differences in their ability to hydrolyze casein and starch, grow in bile medium, utilize pyruvate, and to ferment arabinose, maltose, xylan and N-acetylglucosamine. Five of the Fusobacterium isolates resembled F. russii. The remaining 19 isolates did not resemble previously described species of anaerobic bacteria.  相似文献   

12.
Overproduction and accumulation of melanin cause a number of skin diseases. The inhibitors of tyrosinase are important for the treatment of skin diseases associated with hyper-pigmentation after UV exposure and application in cosmetics for whitening and depigmentation. Reactive oxygen species (ROS) including hydrogen peroxide are generated by chemical substances and metabolic intermediates and cause various diseases including cancer and heart diseases. We have isolated four different lactic acid bacteria (LAB) strains from dairy cow feces and investigated the tyrosinase inhibition and anti-oxidative effects of culture filtrates prepared from the isolated bacteria, which are designated as EA3, EB2, PC2, and PD3. To investigate optimal culture conditions isolated LAB strains, the measurements of tyrosinase inhibitory and anti-oxidative activities were performed. The results of tyrosinase inhibitory activities revealed that Enterococcus sp. EA3 showed about 65% at culture conditions (14 h, 30 °C, pH 8, and 0% NaCl), Enterococcus sp. EB2 about 65% at culture conditions (12 h, 30 °C, pH 9, and 0% NaCl), Pediococcus sp. PC2 about 80% at culture conditions (20 h, 30 °C, pH 6, and 0% NaCl), and Pediococcus sp. PD3 about 80% at culture conditions (20 h, 30 °C, pH 8, and 0% NaCl), respectively. In addition, anti-oxidative activities against four different LAB strains showed approximately more than 30% at optimal conditions for the measurements of tyrosinase inhibitory activities. From the results, we have suggested that the isolated four LAB strains could be useful for a potential agent for developing anti-oxidants and tyrosinase inhibitors.  相似文献   

13.
The microbial community in the human colon contains bacteria that reduce cholesterol to coprostanol, but the species responsible for this conversion are still unknown. We describe here the first isolation and characterization of a cholesterol-reducing bacterium of human intestinal origin. Strain D8 was isolated from a 10−8 dilution of a fresh stool sample provided by a senior male volunteer with a high capacity to reduce luminal cholesterol to coprostanol. Cholesterol-to-coprostanol conversion by strain D8 started on the third day, while cells were in stationary phase, and was almost complete after 7 days. Intermediate products (4-cholesten-3-one and coprostanone) were occasionally observed, suggesting an indirect pathway for cholesterol-to-coprostanol conversion. Resting-cell assays showed that strain D8 could reduce 1.5 μmol of cholesterol/mg bacterial protein/h. Strain D8 was a gram-negative, non-spore-forming, rod-shaped organism identified as a member of the genus Bacteroides closely related to Bacteroides vulgatus, based on its morphological and biochemical characteristics. The 16S rRNA gene sequence of strain D8 was most similar (>99.5%) to those of two isolates of the recently described species Bacteroides dorei. Phylogenetic tree construction confirmed that Bacteroides sp. strain D8 clustered within an independent clade together with these B. dorei strains. Nevertheless, no cholesterol-reducing activity could be detected in cultures of the B. dorei type strain. Based on Bacteroides group-specific PCR-temporal temperature gradient gel electrophoresis, there was no correlation between the presence of a band comigrating with the band of Bacteroides sp. strain D8 and cholesterol conversion in 11 human fecal samples, indicating that this strain is unlikely to be mainly responsible for cholesterol conversion in the human population.  相似文献   

14.
A fraction defined as the inclusions was isolated by banding in CsCl gradients from nuclei of adenovirus 12-infected KB cells. When examined by electron microscopy, the isolated inclusions were relatively homogeneous, finely granular materials of moderate electron density, possibly representing the disintegrated type II or IV inclusions. The conditions of endogenous DNA synthesis in vitro with the inclusions were determined. The product of DNA synthesis in vitro with the inclusions was mainly viral and scarcely cellular, as revealed by DNA-DNA hybridization and methylated albumin kieselgur column chromatography. However, viral DNA synthesized in vitro was smaller (18 S, 22 S) than viral DNA in virions (31 S, 34 S) in neutral and alkaline sucrose gradients. Effects of various treatment of the inclusions on the DNA-synthesizing activity showed that phospholipase C inhibited the activity efficiently. The in vitro DNA synthesis was stimulated by addition of the cytoplasmic extract from adenovirus 12-infected cells and not that from unifected cells. The analysis of the composition of the inclusions showed that the inclusions contained DNA, protein, phospholipid and a small amount of RNA and carbohydrate.  相似文献   

15.
目的:获得高纯度的小鼠支持细胞,用以研究睾丸支持细胞在诱导胚胎干细胞向雄性生殖细胞分化过程中的作用,同时借助睾丸支持细胞减少进行体内诱导试验时可能产生的免疫排斥反应。方法:用胶原酶和胰蛋白酶组合消化结合选择性贴壁法从1周龄昆明白小鼠睾丸分离获得睾丸支持细胞,纯化后进行体外培养,观察其体外培养的生物学特性。结果:睾丸支持细胞体外培养3~4h即贴壁,贴壁后伸出3~4个突起,为成纤维型细胞,在体外培养2~3d即长满全瓶。油红Ο染色显示,其胞质含有大量脂滴。透射电镜观察结果表明,支持细胞核仁周围有卫星核小体。RT-PCR结果显示获得的细胞表达缪勒管抑制物,不表达促黄体素受体和小鼠VASA同源物。结论:获得了较高纯度的小鼠睾丸支持细胞,可以用于诱导小鼠胚胎干细胞向雄性生殖细胞分化的体内和体外试验。  相似文献   

16.
Liu  Qian  Ni  Xueqin  Wang  Qiang  Peng  Zhirong  Niu  Lili  Xie  Meiling  Lin  Yicen  Zhou  Yi  Sun  Hao  Pan  Kangcheng  Jing  Bo  Zeng  Dong 《Probiotics and antimicrobial proteins》2019,11(1):85-91
Probiotics and Antimicrobial Proteins - The present study aimed to isolate an optimal lactic acid bacterial strain from the feces of healthy giant pandas. The strain exhibited good stability at low...  相似文献   

17.
18.
M Kim  H Yi  YJ Cho  J Jang  HG Hur  J Chun 《Journal of bacteriology》2012,194(18):5149-5150
An enteric bacterium, Escherichia coli W26 (KACC 16630), was isolated from feces from a healthy cow in South Korea. Here, we report the draft genome sequence of the isolate, which is closely affiliated with commensal strains belonging to E. coli phylogroup B1.  相似文献   

19.
Anaerobic bacteria resistant to the macrolide antibiotics tylosin and erythromycin were isolated from the feces of swine. One of the strains, 121B, was initially identified by 16S rDNA sequence analysis as an unknown Lactobacillus sp. The strain was found to contain at least two plasmids, one of which was capable of replicating and providing erythromycin and tylosin resistance to Bacillus subtilis, Streptococcus gordonii, and Escherichia coli. DNA sequence analyses of the 4,232-bp plasmid, p121BS, identified one open reading frame encoding a methylase gene highly similar (>98% amino acid identity, >99% DNA sequence identity) to the ermT gene from the Lactobacillus reuteri plasmid pGT633. This is only the second ermT gene to be reported. p121BS also contains two additional open reading frames with significant amino acid similarities to replication proteins from Lactobacillus and other Gram-positive bacteria. Received: 13 October 2000 / Accepted: 4 December 2000  相似文献   

20.
One of the functions of the mammalian large intestinal microbiota is the fermentation of plant cell wall components. In ruminant animals, the majority of their nutrients are obtained via pregastric fermentation; however, up to 20% can be recovered from microbial fermentation in the large intestine. Eight-week continuous culture enrichments of cattle feces with cellulose and xylan-pectin were used to isolate bacteria from this community. A total of 459 bacterial isolates were classified phylogenetically using 16S rRNA gene sequencing. Six phyla were represented: Firmicutes (51.9%), Bacteroidetes (30.9%), Proteobacteria (11.1%), Actinobacteria (3.5%), Synergistetes (1.5%), and Fusobacteria (1.1%). The majority of bacterial isolates had <98.5% identity to cultured bacteria with sequences in the Ribosomal Database Project and thus represent new species and/or genera. Within the Firmicutes isolates, most were classified in the families Lachnospiraceae, Ruminococcaceae, Erysipelotrichaceae, and Clostridiaceae I. The majority of the Bacteroidetes were most closely related to Bacteroides thetaiotaomicron, B. ovatus, and B. xylanisolvens and members of the Porphyromonadaceae family. Many of the Firmicutes and Bacteroidetes isolates were related to species demonstrated to possess enzymes which ferment plant cell wall components; the others were hypothesized to cross-feed these bacteria. The microbial communities that arose in these enrichment cultures had broad bacterial diversity. With over 98% of the isolates not represented as previously cultured, there are new opportunities to study the genomic and metabolic capacities of these members of the complex intestinal microbiota.  相似文献   

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