bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physiology of an Obligately Psychrophilic Marine Pseudomonas Species
Authors: Harder W. , Veldkamp H. 
Published: March 2008

SUMMARYTen obligately psychrophilic bacteria were isolated from North Sea water using conventional enrichment culture techniques at low temperatures. Whereas Arrhenius plots of the growth rate of obligate psychrophiles were linear down to the freezing point of the 0.25% lactate‐artificial sea water medium used, Arrhenius plots of facultative strains showed a deviation from linearity at temperatures a few degrees above 0°. It thus appears that the growth rate of obligate psychrophiles is higher at low temperatures, indicating that in competitive processes in cold natural environments, these organisms are at an advantage. The optimum temperature for growth of one of the isolates, a Pseudomonas sp., was 14.5°; the maximum temperature was between 19 and 20°. Respiration was optimal at 23°, and no inactivation of respiratory activity was found within 5 h at 25°. Cells incubated at supermaximal temperatures showed a release of UV absorbing material. RNA synthesis could not be detected at these temperatures. This is considered to be one of the major factors defining the maximum growth temperature of this organism.
A Note on Penicillinase Production and Penicillin Sensitivity of Staphylococci in the Disc Test
Authors: Holt R. J. 
Published: March 2008

SUMMARYThe sensitivities were determined of 306 isolates of Staphylococcus aurcus and of a smaller number of Staph, albus to various penicillin derivatives, as estimated by a conventional disc method, and their production of penicillinase (β‐lactamase). Many strains of Staphylococci which gave restricted but clear zones of inhibition round discs were shown to produce β‐lactamase.It is suggested that all strains of staphylococci showing such restricted inhibition zones round discs of β‐lactamase‐sensitive penicillins should be reported as relatively resistant to these derivatives.
Growth of Moulds on a Fraction of n‐Alkanes Predominant in Tridecane
Authors: Ratledge C. 
Published: March 2008

SUMMARYSpecies of Helicostylum, Rhizopus, Aspergillus, Penicillium and Fusarium can use as carbon source a fraction of n‐alkanes containing mainly dodecane, tridecane and tetradecane. Yields of mycelium after 21 days were usually <2g/l but the addition of Brussels sprout blanching liquor increased the growth of the Aspergillus, Penicillium and Fusarium spp. 4‐ to 9‐fold. When Penicillium funiculosum and P. soppi were grown on the hydrocarbon fraction, 50% (w/w) of their total fatty acids had carbon chain lengths of < 16. When grown on sucrose the proportion was c. 2% (w/w). A culture of P. soppi grown on sucrose failed to produce short chain fatty acids when the n‐alkanes were substituted as carbon source.
Bacterial Degradation of Plasticized PVC
Authors: Booth G. H. , Cooper A. W. , Robb J. A. 
Published: March 2008

SUMMARYSixtytwo bacterial cultures isolated from a range of deteriorated plastic materials were tested for their ability to degrade a particular PVC mix plasticized with di‐iso‐octyl sebacate. Twentythree of them, mainly members of the genera Pseudomonas and Brevibacterium, gave weight losses of up to 20% in 2 weeks in laboratory conditions. The degradation, which was accompanied by a loss of flexibility of the material, was greatly increased in vigorously aerated cultures.
Shigella spp., Salmonella choleraesuis and Arizona in Rappaport's medium
Authors: Vassiliadis P. 
Published: March 2008

SUMMARYNone of 111 Shigella strains, including all Sh. flexneri types, 2 Sh. boydii types and Sh. sonnei II strains, multiplied in Rappaport's enrichment medium even after a quite heavy inoculation. Moreover the medium proved to be inadequate for the survival of these germs. Of 2 Salm. choleraesuis and 3 Salm. choleraesuis var. kunzendorf strains suspended in saline and inoculated in Rappaport's medium, only 2 of the var. kunzendorf strains multiplied after 48 h. When these strains were suspended in a faecal‐saline dilution the 3 Salm. choleraesuis var. kunzendorf strains grew vigorously in 24 h and 1 Salm. choleraesuis strain grew after 48 h. Only 3 Arizona strains of the 11 tried multiplied vigorously in Rappaport's medium.
Towards the Isolation of Respiratory Syncytial Virus from the Environment
Authors: Kingston D. 
Published: March 2008

SUMMARYRespiratory syncytial virus in 1 μl drops of tissue culture homogenate on polythene gave c. 10% survival on drying and c. 1% survival over 24 h, depending on the vehicle and humidity, but showed no significant loss in liquid suspension over 3 h, or if 100 ft3 of air were blown through the suspension. When drops were deposited on nutrient agar plates there was no significant loss over a period of 3 h, even if 10 ft3 of air were passed over the surface. However, only c. 10% of the virus deposited in this way could be recovered, though 90% of bacteria could be recovered by wiping the agar firmly in the presence of liquid.Air and surface samples were taken in 13 isolation cubicles in which there was an infant suffering from acute bronchiolitis without recovery of the virus, though virus had been isolated from the throats of 8 of the infants, 5 at the time of sampling. The total volume of air sampled was 226 ft3 with liquid impingers and 1146 ft3 on agar. Hartmannellid amoebae were isolated on 2 occasions, one from the air samples and one from surface samples, and an adenovirus type 10 was isolated from the swab of a chair.
Serological Identification Scheme for the Genus Saccharomyces
Authors: Campbell I. 
Published: March 2008

SUMMARYIn a survey of 17 species of the genus Saccharomyces, 4 serological groups were detected by slide agglutination tests. Group A contained S. cerevisiae, S. rouxii, S. acidifaciens and certain strains of S. carlsbergensis; these species may subsequently be identified by agglutination tests with specific sera. S. cerevisiae also occurred in group B, with S. fragilis and S. marxianus. Group C included S. ellipsoidens, a second group of strains of S. carlsbergensis and 8 other Saccharomyces spp. It was not possible to identify all members of this group as antigenically distinct species; only S. chevalieri, S. inusitatus and S. veronae could be identified by specific sera. The fourth group, D, contained the species S. acidifaciens, S. delbrueckii and S. fermentati. The primary classifications into groups A, B, C and D is equally applicable to fluorescence microscopy, cells of one group in a culture of another group being detectable even at low levels of contamination.
Influence of Amino Acids, Carboxylic Acids and Sugars on the Growth of Methylococcus capsulatus on Methane
Authors: Eroshin V. K. , Harwood J. H. , Pirt S. J. 
Published: March 2008

SUMMARYThe influence of 3 types of compounds (L‐amino acids, carboxylic acids and sugars) on the growth of Methylococcus capsulatus in Petri dishes was investigated. Increase in colony diameter was used as the growth parameter. L‐amino acids and carboxylic acids which are normal metabolic intermediates prevented growth in low concentrations. Threonine, leucine, histidine and glycine were especially inhibitory; c. 0.01% was sufficient to suppress growth completely. Glutamic acid at 0.1 % concentration completely suppressed growth but at 0.005% markedly stimulated growth; similar effects were shown by lysine, methionine, glutamic acid, tryptophane, tyrosine, proline and citric acid. Among the sugars, glucose was the most potent growth inhibitor; maltose and sucrose had practically no effect.
Studies on the Mineral Nutrition of the Bulbiformin Producing Strain of Bacillus subtilis
Authors: Mahmood M. 
Published: March 2008

SummaryThe elements S, P and K were shown to be essential for both growth and bulbiformin production by Bacillus subtilis. The optimum requirements for these elements were 40, 50, 710 p/m, respectively, for both growth and antibiotic activity. The requirement of K for maximum growth was higher than for antibiotic activity. Calcium sulphate and calcium phosphate as S and P sources were particularly favourable for growth. Calcium or potassium sulphate and Na2S were suitable sources of S, and Ca3(PO4)2, NaH2PO4, K2HPO4 and MgHPO4 suitable sources of P for bulbiformin production.
Medium Volume and the Survival of Serratia marcescens
Authors: Domey R. G. , Saurino V. R. , Simon G. T. 
Published: March 2008

SummaryExperiments were designed to test the null hypothesis that volume of agar medium in 100 mm Petri dishes has no influence on the colony count of the facultative organism, Serratia marcescens. With a constant inoculum in 9, 12, 15 and 18 ml volume of medium the surface counts were statistically equivalent, but the subsurface counts increased as a direct function of volume variation. Over the range studied, at the P= 0.95 level, the null hypothesis was accepted for surface colony counts but was rejected for subsurface colony counts.
The Metabolic Availability of Phenol Analogues to Bacterium NCIB 8250
Authors: Beveridge E. G. , Tall D. 
Published: March 2008

SummaryOf the monosubstituted phenols examined only 3 could be utilized by bacterium NCIB 8250 as sole carbon sources for growth. Only 3‐ and 4‐fluorophenols, and 4‐chlorophenol, in addition to phenol and catechol, were oxidized by the phenol metabolizing pathway. Fluoride ions were liberated during the metabolism of 3‐ and 4‐fluorophenols and accumulation of toxic intermediates was indicated at the higher substrate levels of the fluorophenols and 4‐chlorophenol. Phenol analogues inhibited phenol metabolism to varying degrees and some may have exerted an uncoupling effect on phenol metabolism. Only the fluorophenols and phenol induced phenol metabolizing activity in growing cells. Growth in the presence of certain other analogues resulted in cells whose inductive lag phase towards phenol was reduced.
Salmonellae in Meat and Poultry, Poultry Plant Cooling Waters and Effluents, and Animal Feedingstuffs
Authors: Patterson J. T. 
Published: March 2008

SummaryAlthough a low incidence of salmonellae had been found in 735 broiler chicks in 1961, none were found in 803 carcasses from 4 processing plants in 1966. Small numbers, mainly S. typhimurium, were found in the drains of 2 of these plants when swabs were left for several days. No isolations were made from the waters used to cool broilers or turkeys, or from 84 turkey carcasses. However, 39 of 444 (9%) of duck carcasses harboured S. typhimurium, and 9 of 22 (41%) of duck cooling waters were positive. Two isolations of S. typhimurium were made from 38 samples of pork sausages, and one of S. dublin from 125 samples of frozen boned‐out beef. Three of 29 samples of cooked poultry meat were positive for S. typhimurium. In animal feedingstuffs 8 of 112 (7%) of samples of meat and bone meal had 7 different serotypes present, and salmonellae were also found in feather meal, blood meal and pig compound meal. S. typhimurium phage type 23 has been isolated from ducks, poultry meat, pork sausages and meat and bone meal, suggesting a chain of infection. The significance of the isolations of salmonellae from the various sources is discussed, and some methods of control suggested.
Media Selective for Listeria monocytogenes
Authors: Kramer Pamela A. , Jones Dorothy 
Published: March 2008

SummaryOf a number of substances tested for inclusion in media selective for Listeria monocytogenes, thallous acetate and nalidixic acid gave encouraging results at 30° and pH 7.0. Using these selective media, L. monocytogenes was recovered from artificially infected manure, soil, silage and grass.
Serological Response Produced in Chickens by Three Strains of Mycoplasma gallisepticum
Authors: Roberts D. H. 
Published: March 2008

SummaryThree strains of Mycoplasma gallisepticum, S6, F and WS7, were used to infect 3 groups of broiler chickens. Serum antibody response was investigated using the stained antigen plate agglutination (SA) test and the haemagglutination inhibition (HI) test. The HI test was more strain specific and was associated with low molecular weight (IgG) antibodies. Chickens infected with one strain did not always give an HI reaction with the heterotypic antigen. The SA test was associated with high molecular weight (IgM) antibodies. Chickens infected with the three strains always reacted serologically with the homotypic and heterotypic SA antigens. In chickens infected with the S6 and WS7 strains, the IgM and IgG antibody titres remained consistently high during the period of the experiment; in chickens infected with the F strain, the IgG antibodies had disappeared by 7 weeks after infection although the IgM antibodies persisted.
Interactions in the Recovery of Salmonella typhimurium Damaged by Heat or Gamma Radiation
Authors: Corry Janet E. L. , Kitchell A. G. , Roberts T. A. 
Published: March 2008

SummaryGrowth of two strains of Salmonella typhimurium in nutrient broth, selenite and tetrathionate broths, at 37 and 43°, after damage by heat or γ radiation, was compared with that of undamaged cells. Counts at 37° were made on 6 media initially and after enrichment for 24, 48 and 72 h. Analyses of variance showed complex interactions of cell damage, enrichment medium, temperature and duration of enrichment, and plating medium.The most generally satisfactory combination of factors involving use of selective inhibitors appears to be enrichment in tetrathionate broth at 37° followed by plating at 48 h on brilliant green, Wilson & Blair, or brilliant green‐phenol red agar. After attaining maximum numbers in 18 h in selenite broth, salmonellae died off rapidly or, if heat damaged, may fail to grow at all in this enrichment medium. Incubation at 43° in either selenite or tetrathionate medium, except after pre‐enrichment, is not recommended for heat damaged salmonellae.
Aniline Utilization by a Soil Pseudomonad
Authors: Walker N. , Harris D. 
Published: March 2008

SummaryA Pseudomonas sp., isolated from soil, grew with aniline as its sole carbon source. Washed cells oxidized aniline by an induced enzyme system and liberated ammonia. Washed, aniline‐grown organisms oxidized without lag aniline, catechol, p‐aminophenol and o‐ and m‐toluidine.
The Location of Chemical Components on Ultrathin Sections of Bacillus cereus Embedded in Glycol Methacrylate
Authors: Walker P. D. 
Published: March 2008

SummaryThe structure of Bacillus cereus during sporulation and germination is described after aldehyde fixation and embedding in a water soluble resin. The resistance of ribosomes to digestion with ribonuclease has been investigated during the various phases of growth. Increasing resistance to digestion was observed at a stage just prior to the development of the spore coat. The location of polysaccharides on similar sections corresponded with their location previously found in osmic acid fixed material.
Combined Effect of Salt Concentration and Redox Potential of the Medium on the Initiation of Vegetative Growth by Clostridium welchii
Authors: Mead G. C. 
Published: March 2008

SummaryFour strains of Clostridium welchii grew in a medium containing 6% (w/v) of NaCl within 14 days at 37°. In one instance growth was obtained with 7% of NaCl from a large, but not a small, inoculum. Three of the strains grew from a large inoculum in the presence of 0.5 % of NaCl at Eh values of + 194 to + 238 mv. In a medium containing 5% of NaCl no growth occurred unless the Eh level was considerably reduced. The fourth strain was less affected until the NaCl concentration was increased to 6%.
Viability of Clostridial Spores and the Requirements of Damaged Organisms
Authors: Futter B. V. , Richardson G. 
Published: March 2008

Summary.A method for counting viable anaerobic spores by roll tubes incubated in an atmosphere of hydrogen compared favourably with other techniques. Reproduction of environmental conditions in individual anaerobic jars did not significantly contribute to the overall error (Coefficient of Variation of viable count, 6·7%). Colony counts did not show a Poissonian distribution, and the significance of this is discussed. Optima for some conditions for counting 4 species of Clostridium and for suspensions of spores of Cl. welchii damaged by heat, γ‐rays or ethylene oxide have been established. Damaged spores were more exacting in their cultural requirements than were control organisms, and considerable variation in incubation temperature optima was found according to the sublethal treatment employed.
Ultrasound and Vortex Stirring as Bacteriological Sampling Methods for Foods
Authors: Sharpe A. N. , Kilsby D. C. 
Published: March 2008

Summary.The efficiencies of an ultrasonic cleaning tank (insonation) and a vortex stirrer for bacteriological sampling of foods were compared with a standard homogenization method. Insonation gave good recovery of micro‐organisms in a limited range of foods, and its main advantage was the very low debris content of the resultant suspension. Vortex stirring was a much more useful method for routine work, combining convenience and rapidity of sample preparation with low running costs, low noise level and easily pipettable suspensions. The high concentration of organisms obtained by vortex stirring may aid detection of low levels of contamination.
Observations on the Sporicidal Action of Vegetable Oils Used in Fish Canning
Authors: Dallyn H. , Everton J. R. 
Published: March 2008

Summary.The putrefactive anaerobe PA3679 was used to investigate possible factors present in vegetable oil which might influence the heat resistance of bacterial spores present in processed tuna fish. A water soluble component of some olive and groundnut oils significantly reduced the heat resistance of spores of this organism. Autoxidation factors in vegetable oils are suggested as the sporicidal or sporistatic agents. Attempts to identify the factor with malonaldehyde were not successful but there was some evidence that a similar carbonyl or its peroxide precursor might be involved.
A Study of the Effect of Carbon Dioxide on the Germination and Outgrowth of Spores of Clostridium butyricum using a Slide Culture Technique
Authors: Hambleton R. , Rigby G. J. 
Published: March 2008

Summary.A slide culture technique for the study of germination of clostridial spores on solid media is described in which the gaseous environment can rapidly be altered. Two spore suspensions of Clostridium butyricum NCTC 7423 prepared on different media germinated slowly and at different rates in oxygen‐free nitrogen (OFN) in the absence of CO2 when incubated on the same solid germination medium. The admission of 5% of CO2 to spores germinating in OFN caused a sharp increase in germination to almost 100% within 10 min. The results show that the sporulation medium plays a part in determining the carbon dioxide requirement for germination of these spores. A surface spread colony counting technique is also described, and the results using this technique stress the importance of the medium used.
Trace Elements and Reproduction of Leptospirae
Authors: Burger G. , Fuchs G. H. P. 
Published: March 2008

Summary.Low concentrations of Zn and Co salts in the medium stimulated growth of several strains of 2 species of Leptospira, but high concentrations inhibited growth. Low concentrations of Cu increased the growth rate of saprophytic leptospirae but did not affect parasitic strains; high concentrations inhibited all strains. In a Zn‐containing medium, the addition of increasing amounts of Cd was increasingly inhibitory to both species. The addition of 0·2 × 10−6 g of Zn(NO3)2. 6H2O and 10−9g of CoSO4.7H2O/ml of Korthof's medium is recommended. Saprophytic leptospirae grow better with 10−6g of CuSO4.5H2O/ml of medium.
Microbiological Assay of the β‐Exotoxin of Bacillus thuringiensis
Authors: Rosenberg G. , Carlberg G. , Gyllenberg H. G. 
Published: March 2008

Summary.The β‐exotoxin of Bacillus thuringiensis var. thuringiensis suppressed the growth of Sarcina flava and certain other bacteria. The antibacterial effect on S. flava was correlated with the amount of exotoxin as determined by absorption at 260 nm as well as to the toxic response in bioassays using the larvae of the housefly. Growth inhibition of S. flava could be shown in cup plate assay of the cellfree supernatant of B. thuringiensis var. thuringiensis cultures, prepurified and purified β‐exotoxin. The results showed that it was possible to use S. flava in a quantative assay of the β‐exotoxin activity of B. thuringiensis.
Glucose Fermentation Endproducts of Erwinia spp. and other Enterobacteria
Authors: White J. N. , Starr M. P. 
Published: March 2008

Summary.The endproducts formed by Erwinia spp. and other enterobacteria from the anaerobic fermentation of glucose were determined by thin‐layer chromatography and other micromethods. The 71 strains examined fell into 15 mixed acid fermentation end‐product patterns of the sort which are considered to be characteristic of the Enterobacteriaceae. The patterns ranged from the detectable formation by 6 strains of all 7 of the products which were determined (carbon dioxide, succinate, lactate, formate, acetate, 2,3‐butanediol, and ethanol) to the detectable formation by one strain of only two (carbon dioxide and lactate); 32 strains formed 6 of the products; 21 strains formed 5 of the products; 9 strains formed 4 of the products; two strains formed 3 of the products. Each of the named species (nomenspecies) of the genus Erwinia does not, in general, have a characteristic pattern of fermentation endproducts; the nonphytopathogenic enterobacteria share many of the patterns shown by Erwinia spp.
A Rapid Test for Biodegradability of PVC Film by Pseudomonads
Authors: Sharpe A. N. , Woodrow M. N. 
Published: March 2008

Summary.Biodegradability of plasticized PVC film by a Pseudomouas fluorescens strain was assessed quickly by determination of ammonia produced during endogenous respiration of the organism. Values for ammonia production from 52 PVC samples after 48 h showed an excellent inverse correlation with weight loss of the film as determined after 14 days, and can form the basis of a rapid method for assessing biodegradability.
Relationships between Estimates of Binding of Antimicrobial Agents by Macromolecules, based on Physiochemical and Microbiological Data: Benzoic Acid and a Nonionic Surfactant
Authors: Coates D. , Richardson G. 
Published: March 2008

ABSTRACT.Binding of benzoic acid to a nonionic polyoxyethylene surfactant has been investigated by equilibrium dialysis and a microbiological viable count technique. The results indicate that the antimicrobial activity of benzoic acid in this solubilized system can be equated with the free acid in solution in the aqueous phase. Potentiation by low concentrations of several nonionic macromolecules does not occur.