摘要:

Summary:The addition of 50 μg of sulphamezathine/ml to egg‐tellurite‐glycine‐pyruvate agar was effective in suppressing the growth and swarming ofProteusspp. Small numbers ofStaphylococcus aureus(103/g) could be recovered quantitatively on the modified medium in the presence of up to 106/g of mixedProteus vulgarisandProteus mirabiliss

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04814.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Serological methods are described by which organisms of the genusPseudomonasand related genera can be compared. More specific relationships are demonstrated by agglutination techniques or agar diffusion with trichloroacetic acid extracts; less specific relationships are shown by agar diffusion with disintegrated cell preparations. Up to three strain specific antigens may be found and at least six antigens are widely distributed amongst strains of the generaPseudomonas, Achromobacter, VibrioandAeromonas.The results obtained so far indicate little or no agreement with any accepted taxo‐nomic divisions. Evidence is presented which suggests that most of the antigens detectable by agar diffusion techniques are polysaccharide in nature rather than protei

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04815.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:A simple, rapid and efficient technique is described for the isolation of mutants ofBacillus subtilisin which the synthesis of mycobacillin, an antifungal antibiotic, is blocked. Suspensions of a chosen culture were subjected to ultraviolet radiation and then plated; colonies failing to produce antibiotic were located by flooding the incubated plates with agar seeded with sensitive fungi such asCandida albicansandAspergillus niger. The method is also applicable for the isolation of high potency strains.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04816.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:The results are given of a biochemical study of 21 strains of C27. An Adansonian analysis was carried out by electronic computer on these strains and theAeromonasstrains studied in the previous paper (Eddy, 1962). The analysis confirms the proposal that the C27 strains should be excluded from the genusAeromonasand a description of the new genus,Plesiomonas(Habs&Schubert, 1962), for these organisms is given. The analysis did not clearly establishAer. formicansas a species distinct fromAer. punctata.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04817.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Five strains of bacteria were irradiated, suspended in heart infusion broth or in phosphate buffer, in aerated or anoxic conditions, at temperatures of 10–13° or ‐79°. Survivors under the different conditions were enumerated by plate counts on heart infusion agar.Exponential survivor‐dose curves were obtained with aPseudomonasstrain and withEscherichia coliB/r when irradiated at room temperature with aeration, whereas anAlcaligenesstrain and 2 strains ofStreptococcus faeciumgave sigmoid curves. The decreased radiosensitivity in the frozen state was measured by comparing the D10values for exponential curves, or for the exponential portion of sigmoid curves, with that observed for irradiation at room temperature with aeration. This ‘D10ratio’ svaried between 2°5 and 8·5. For theAlcaligenesstrain it was about 4, whether the frozen irradiation took place in the presence or absence of oxygen. With thePseudomonasirradiated in the frozen state in the absence of oxygen the ‘D10ratio’ was usually about 1·5 times higher than when oxygen was present. The highest ratio (8·5) was obtained for anoxic irradiation of thePseudomonasstrain.In general, the shapes of survival curves for frozen irradiation differed from those obtained at room temperature. The sigmoid curves for theAlcaligenesstrain irradiated under aerobic conditions when frozen showed a marked decrease in extrapolation numbers.E. coliB/r when frozen in heart infusion broth gave a double exponential curve with a shallow slope initially, followed by a steeper slope. The most radiation resistant strain,Strep. faeciumR53, gave sigmoid curves with a D10value of 300 Krads when frozen, and was then of similar resistance toClostrid

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04818.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Bacillus pumilusspores, irradiated under aerobic conditions, were inactivated exponentially at the same rate whether they were at room temperature (10–13°) in phosphate buffer or at ‐79° in phosphate buffer or in heart infusion broth.Clostridium welchiispores were irradiated in Robertson's cooked meat medium under anaerobic conditions. With unheated spores, and those subjected to a heat shock before irradiation, the inactivation rate was the same at room temperature and ‐79°. The same applied to spores heat shocked after irradiation for doses up to 450 Krads, but above this dose level the spores irradiated frozen were more sensitive.The effect of the heat shock, whether applied before or after irradiation, was to increase the number of survivors, and the proportionate increase appeared to vary w

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04819.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Media making on a large laboratory scale has hitherto involved considerable manipulation and some personal risk. The report describes an apparatus which obviates these disadvantages and also saves time.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04820.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Fluorescent labelled specific antisera against spores and vegetative cells have been used as stains to follow the antigenic changes that occur on the surface ofClostridium sporogenesduring sporulation and germination.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04821.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

摘要:

Summary:Fluorescent labelled specific antisera have been used to distinguish between types A, B and F, types C and D, and type E ofClostridium botulinum.

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04822.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY

ISSN:0021-8847    

DOI:10.1111/j.1365-2672.1964.tb04823.x

出版商:Blackwell Publishing Ltd    

年代:1964

数据来源: WILEY