Sensitivites in vitro to antimicrobial drugs of bovine mycoplasmas isolated from respiratory and genital tracts

A total of 155 Mycoplasma strains were examined for sensitivity to nine antibiotics and four nitrofurans by the agar dilution method. They consisted of 69 strains of Mycoplasma bovirhinis, 33 strains of M. bovigenitalium, 49 strains of Acholeplasma laidlawii and four strains of A. modicum isolated from the nasal secretions, tracheas and lungs of calves manifesting respiratory symptoms and from bovine genital tracts collected at a slaughterhouse. As a result, furamizole and mitomycin C showed the strongest growth-inhibiting effect on all the strains. They were followed in this effect by kitasamycin tartrate, spiramycin adipate, tylosin tartrate, tetracycline-HCl and chloramphenicol. Furthermore, these five drugs were followed in the effect by furazolidone, nitrofurantoin and sodium nifurstyrenate. Fradiomycin sulfate and kanamycin sulfate showed only little effect on all the strains. Erythromycin lactobionate showed a strong growth-inhibiting effect on the Acholeplasma strains, but not on the Mycoplasma strains. There were some cross resistant strains of the Acholeplasma species to the effects of the macrolides.     

Probiotic potential of enterococci isolated from canine feed

Enterococci isolated from 28 different commercially available feeds (10-1000 CFU/mL) were identified and their probiotic potential was determined. Species identification of 22 selected strains was performed by intergenic length-polymorphism analysis (tRNA-PCR); PCR products were analyzed using capillary electrophoresis. Six strains were allotted to the species Enterococcus faecium, four to E. faecalis, one to E. hirae; the remaining strains were not classed. The strains were sensitive to vancomycin, ampicillin, tetracycline and rifampicin. They were able to adhere to human as well as canine intestinal mucus. They produced lactic acid (0.99-1.04 mmol/L) and most of them were urease-positive with sufficient survival in 5 % Oxgall-bile. They did not show any inhibitory activity due to antimicrobial substances. Plasmid DNA was detected in 8 strains, the bands responding to small molecular size (10 kbp). Considering all probiotically important properties, E. faecium strain EE3 was suggested as potential feed additive.     

产果胶酶菌株的筛选

从不同来源的生物样品中分离到产果胶酶菌株,采用刚果红染色法和十六烷基三甲基溴化铵沉淀法进行初筛,通过摇瓶发酵试验进行复筛,最终获得2株果胶酶活力较高的细菌G16和G25,其酶活力分别达到6．37万U／mL和6．84万U／mL。     

Characterization of Leuconostoc oenos Isolated from Oregon Wines

This study was designed to characterize isolates of Leuconostoc species from Oregon wines. Gram-positive cocci were isolated, and their biochemical properties and abilities to decompose malic acid were determined. All of the isolates were heterofermentative, catalase negative, and facultatively anaerobic and occurred in pairs and chains. They produced acid from glucose, fructose, mannose, ribose, cellobiose, trehalose, and salicin but not from sucrose or lactose. They did not produce ammonia from arginine or dextran from sucrose. They grew at pH values of less than 4 and in 10% ethanol. Most but not all strains produced lactic acid and carbon dioxide from malic acid, as determined by paper chromatography and respirometry, respectively. These malolactic bacteria were considered to be strains of Leuconostoc oenos. We compared these isolates with reference strains for relative growth at pH values of 4.0, 3.5, 3.0, and 2.8 at 22°C. The isolates were similar in their growth responses at the two highest pH levels. At pH 3.0 and 2.8, however, the strains failed to grow but revealed variable abilities to dissimilate malic acid.     

老鼠簕(Acanthus illicifolius L.)根际内生菌分离与活性评价

从老鼠簕(Acanthus illicifolius L.)根际土壤和植物根、叶、茎中共分离得到97株微生物,其中包括27株放线菌,44株细菌以及26株真菌,并且土壤中的分离得到的微生物最多。对获得的菌株进行细胞毒活性、抗金黄色葡萄球菌和抗白色念珠菌的测定,结果发现细菌的活性百分比最高,而放线菌和真菌活性百分比相对较小。     

Isolation ofBacillus schlegelii,a thermophilic,hydrogen oxidizing,aerobic autotroph,from geothermal and nongeothermal environments

Thermophilic hydrogen-oxidizing strains forming round, terminal endospores were isolated from geothermal areas. They were neutrophilic and facultatively autotrophic. They resembledBacillus schlegelii, a thermophilic hydrogen bacterium found so far only in cold environments. Phenotypic similarities, as well as DNA G+C content and DNA:DNA homologies, clearly revealed that the isolated strains belonged to the taxospeciesB. schlegelii. Hence, the strains ofB. schlegelii found in cold environments are probably allochthonous, their origin being geothermal and volcanic areas.     

辣椒上CMV株系鉴别寄主的筛选与应用

根据“基因对基因”理论和日本小室与都凡按寄主的科属关系及被害症状划分株系的方法,研究了辣椒CMV的“基因型株系”和“致病型株系”。从373个甜、辣椒品种(系)中,筛选出一套抗性不同的差别品种,编号为:LS-8501(HR)、LS-8502(R)、LS-8503(T)、LS-8504(S)、LS-8505(HS)。用这套差别品种做“基因型”株系鉴别寄主,将59个CMV分离物划分为5个株系,命名为:CMV-P0,CMV-P1,CMV-P2,CMV-P3,CMV-P4。又从7科39种不同科属寄主值物中,筛选出一套“致病型”株系的鉴别寄主谱7种,用这套鉴别寄主将59个CMV分离物划分为5个株系群,即十字花科株系群,藜科株系群,茄科、葫芦科株系群,豆科株系群,普通黄色花叶株系群。文中比较了两种方法划分的株系致病性与辣椒病症表现型之间的关系,以及各株系的分布。还讨论了“基因型”鉴别寄主谱及“基因型”株系划分方法盼学术价值和实用性,比较了5个株系与国内外已分化的CMV株系的异同点。     

Isolation and identification of marine chitinolytic bacteria and their potential in antifungal biocontrol

Chitinolytic marine bacterial strains (30) were isolated from the sea dumps at Bhavnagar, India. They were screened as chitinase producers on the basis of zone of clearance on chitin agar plates incorporated with calcofluor white M2R for the better resolution. Out of these, three strains namely, Pseudomonas sp., Pantoea dispersa and Enterobacter amnigenus showed high chitinase production. They were also found to produce proteases and therefore have a good potential for use as antifungal biocontrol agents for the control of fungal plant pathogens. These strains could degrade and utilize the mycelia of Macrophomina phaseoliena (Tassi) Goidanich and Fusarium sp. In vitro, these strains could inhibit the growth of Fusarium sp. and M. phaseolina. The culture filtrate inhibiting hyphal elongation was observed microscopically.     

脱落酸产生菌的初步筛选

从三份不同来源的土样中分离出４０株真菌。以脱落酸（±）ＡＢＡ为对照,通过移块法从中筛出１５株脱落酸产生菌,并进一步从中复筛出１０个较优的脱落酸产生菌,用丙酮－乙酸乙酯抽提,证实其中８株能产生脱落酸。通过对菌落培养特征和形态特征的观察,初步鉴定它们分属于萄葡孢属、曲霉属和青霉属。     

Lactobacillus harbinensis sp. nov., consisted of strains isolated from traditional fermented vegetables 'Suan cai' in Harbin, Northeastern China and Lactobacillus perolens DSM 12745

Taxonomical analysis of two genetically distinguished Lactobacillus strains isolated from traditional Chinese fermented vegetables ‘Suan cai’ was performed. They formed l-lactate from glucose, were facultatively heterofermentative, and had a DNA G+C content of 53–54 mol%. They fermented d- and l-arabinose. They produced lactate, ethanol and acetate from gluconate at a molar ratio of 1.1:0.4:0.7. Phylogenetic analysis of 16S rDNA revealed that the two strains were closely related to L. perolens. DNA–DNA hybridization analysis revealed that the two strains were different from L. perolens type strain DSM 12744 and formed a separate cluster with L. perolens DSM 12745. G+C molar content of DNA of the former is 51%, whereas those of the latter strains were in the range of 53–54%. Based on the results, we propose that the new species be named L. harbinensis sp. nov. and that L. perolens DSM 12745 be reclassified as L. harbinensis DSM 12745. The type strain of L. harbinensis DSM 16991^T (=AHU 1762^T=SBT 10908^T).     

Near-ultraviolet sensitivity of skin fibroblasts of patients with bloom's syndrome

Near-ultraviolet survival of colony forming ability was compared between fibroblast strains from normal individuals and seven strains from Bloom's Syndrome patients using monochromatic light at 313 nm. Six BS strains possessed abnormal survival properties. Two strains lacked the low dose shoulder, which is characteristic for normal fibroblasts, but their overall sensitivity was in the normal range. Four BS strains were hypersensitive and possessed biphasic survival curves with a sharp initial drop. They mimick in culture the characteristic solar sensitivity of BS patients.     

Secondary antimicrobial metabolites produced by thermophilic Bacillus spp. strains VK2 and VK21

A collection of thermophilic strains of the genus Bacillus was made. The strains were screened for antimicrobial activity. Strains VK2 and VK21 isolated from thermal springs of the Kamchatka Peninsula, and antagonistic to several gram-positive bacterial species were chosen for further investigation of antibiotics produced by them. Restriction analysis of DNA coding for 16S rRNA showed that both strains can be assigned to Bacillus licheniformis. It was shown that the lytic activity of strains VK2 and VK21 was not related to the synthesis of hydrolytic enzymes. The maximum level of antimicrobial activity in the growth medium was found to correspond to the beginning of the stationary growth phase. Addition of manganese sulfate induced sporulation and altered significantly the time course of antibiotic production in both strains. Active metabolites were extracted with n-butanol. They survived boiling for 30 min and were resistant to trypsin and chymotrypsin but were partly hydrolyzed by pronase. They were stable at a pH range of 2.0-9.0.     

Antimicrobial activity of Staphylococcus xylosus from Italian sausages against Listeria monocytogenes

One hundred and twenty-five isolates of Micrococcaceae from Italian salami were tested for antagonistic activities against Listeria monocytogenes. Four isolates, identified as Staphylococcus xylosus , inhibited the growth of all five strains of L. monocytogenes tested. The antagonistic substances produced by strains 39A and 41A were inactivated by some proteases, whereas those from strains 1E and 27E were inactivated only by esterase and lipase. They are neither bacteriophages, nor lytic enzymes like lysostaphin.     

Yersinia enterocolitica, indole-negative and indole-positive biotypes. Isolation, identification and sensitivity to chemotherapeutics

A population of 200 Y. enterocolitica strains of the serotype 03 and 100 strains belonging to other serotypes mostly, however, to the biotype 1 were examined for their sensitivity to chemotherapeutics. The serotype 03 strains were obtained from human material of diarrhoeal cases, the origin of other serotypes was various. They originated from human extraintestinal material, animals, water and foods. To summarize their results, the authors elaborated an antibiogram presented in graphs.     

Use of pulse-field electrophoresis for intraspecies differentiation of methycillin-resistant, coagulase-negative strains of Staphylococcus aureus (MRSA-CN)

Strains showing a negative reaction in tube test for coagulase accounted 10 to 20% of all Staphylococcus aureus isolated from patients of PSK No. 1 in Warsaw. They are MRSA as well as MSSA strains. 37 coagulase-negative isolates of MRSA were examined using the method depending on digestion of whole cell DNA with SmaI enzyme and electrophoretic separation of the obtained fragments in the pulsed field (PFGE). It was shown that majority of the strains (26 from 37) had individual, unique patterns of bands. However, the two groups of strains were also observed showing a great similarity. The larger group contained 8 strains which were obtained from patients from different wards and the smaller group contained 3 strains obtained from patients from one hospital ward. The obtained results showed that among coagulase-negative MRSA strains are not only sporadic strains but also strains with probably epidemic properties, derived from different clones.     

具抑菌活性海洋微生物的筛选

从上海郊区海域采集的海水、海泥样中分离出193株海洋细菌,对其进行抑菌活性菌株的筛选。对分离出的菌株分别利用琼脂块法和管碟法进行初筛和复筛,结果显示有29株海洋细菌具有抑菌活性,占总分离菌株的15%,其中抑菌能力较强的G4抑菌谱较广,同时能抑制革兰氏阳性和阴性指示菌。     

beta-Glucuronidase activities of intestinal bacteria determined both in vitro and in vivo in gnotobiotic rats

The beta-glucuronidase activities of bacterial strains isolated from the rat intestinal tract were studied both in vitro in culture media and in vivo in the intestinal contents of gnotobiotic rats. Only 50 of 407 strains tested were found to be positive in vitro. They belonged to the three genera Clostridium, Peptostreptococcus, and Staphylococcus. The in vitro-negative strains were also negative in vivo. The beta-glucuronidase activities of the beta-glucuronidase activities of the positive strains were generally greater in vivo than in vitro. The highest in vivo activities were found in the intact bacterial cells and in the soluble fractions prepared from disrupted pellets. There was a discrepancy between the activities obtained from both conventional and gnotobiotic rats harboring selected positive strains, suggesting that the main beta-glucuronidase-positive strains have not yet been isolated from the intestines of conventional rats.     

beta-Glucuronidase activities of intestinal bacteria determined both in vitro and in vivo in gnotobiotic rats.

The beta-glucuronidase activities of bacterial strains isolated from the rat intestinal tract were studied both in vitro in culture media and in vivo in the intestinal contents of gnotobiotic rats. Only 50 of 407 strains tested were found to be positive in vitro. They belonged to the three genera Clostridium, Peptostreptococcus, and Staphylococcus. The in vitro-negative strains were also negative in vivo. The beta-glucuronidase activities of the beta-glucuronidase activities of the positive strains were generally greater in vivo than in vitro. The highest in vivo activities were found in the intact bacterial cells and in the soluble fractions prepared from disrupted pellets. There was a discrepancy between the activities obtained from both conventional and gnotobiotic rats harboring selected positive strains, suggesting that the main beta-glucuronidase-positive strains have not yet been isolated from the intestines of conventional rats.     

Characterization of black-pigmented Bacteroides strains isolated from animals

The aims of the study were: the isolation of strains of black-pigmented Bacteroides from the gingival sulcus of different animals, their biochemical and immunological characterization and comparison of their properties for classification within the genus. A total of 104 strains, isolated from cats, dogs, racoons and a jaguar, were characterized on the basis of fermentation of carbohydrates, metabolic end products, haemagglutination studies, enzymatic activities, catalase production and indirect immunofluorescence. No differences were observed between the strains regardless of their animal origin. The strains did not ferment carbohydrates, produce phenylacetic acid, show an array of enzyme activities or agglutinate sheep red blood cells. They were catalase-positive and so differed from the human oral strains of Bact. gingivalis. Immunofluorescence microscopy revealed that the animal strains shared at least one major antigen with Bact. gingivalis but none with Bact. asaccharolyticus. Apart from their catalase activity, the animal strains isolated were similar to those of human Bact. gingivalis strains.     

1052株烧伤创面病原菌及其药敏分析

目的为了指导临床合理应用抗生素,提高治愈。方法所有标本均采用常规细菌培养,纸片扩散法对1052株病原菌行耐药性监测。结果360例患者送检标本1136份,检出1052株病原菌,其中G^-杆菌611株,占总检出率的58．08％,G^-球菌416株（39．54％）,MRSA253株,占金黄色葡萄球菌的60．82％,真菌25株（2．38％）。结论烧伤感染常见为铜绿假单胞菌,不动杆菌,变形杆菌,金黄色葡萄球菌和MRSA,且耐药性强。