bluuebunny/crossref_metadata_2025 huggingface dataset:
Studies on the Mode of Action of Some Cephalosporin Derivatives
Authors: Fountain R. H. , Russell A. D.
Published: March 2008

7‐(s‐benzylthioacetamido)‐cephem‐3‐ylmethyl‐N‐dimethyldithiocarbamate‐4‐carboxylic acid (cephalosporin 7/30) prevented benzylpenicillin from inducing spheroplasts in Escherichia coli, and inhibited growth of preformed spheroplasts. These effects were also noted with dimethyldithiocarbamate (DMDT), the side‐chain at position 3 in 7/30. Cephalosporin 7/30 inhibited growth of protoplasts of Bacillus megaterium and Streptococcus faecalis. At high concentrations, 7‐[(2‐thienyl)acetamido]‐cephem‐3‐ylmethyl‐N‐dimethyldithiocarbamate‐ 4‐carboxylic acid (cephalosporin 87/30), with the same side‐chain at 7 as cephaloridine but with DMDT at position 3, prevented spheroplast formation in E. coli, and inhibited the growth of preformed spheroplasts. However, at lower concentrations, 87/30 induced spherical forms in E. coli. The other cephalosporins, tested induced spheroplasts in E. coli and had no effect on protoplasts.
The Nitrogen Nutrition of Soil and Herbage Coryneform Bacteria
Authors: Owens J. D. , Keddie R. M.
Published: March 2008

The nitrogen nutrition of 93 strains of soil and herbage coryneform bacteria and 16 named strains of Arthrobacter and Cellulomonas was examined. In testing for the ability of coryneform bacteria to utilize inorganic nitrogen as sole nitrogen source it was found necessary to use a medium containing a balanced mineral base and a suitable metal chelating agent in order to obtain reproducible results. A suitable medium is described. When provided with essential vitamins, 90% of soil isolates utilized inorganic nitrogen as sole nitrogen source while only 30% of herbage isolates did so. Sixty per cent of herbage isolates utilized inorganic nitrogen as major nitrogen source when provided with l‐methionine in addition to vitamins, whereas no soil isolate showed a requirement for methionine. For a small residue of strains from each habitat the substrate nitrogen requirements were not determined. Of the named strains examined A. terregens utilized inorganic nitrogen as major nitrogen source when provided with methionine and vitamins while the remainder utilized inorganic nitrogen as sole nitrogen source. For 4 Arthrobacter spp. the nitrogen requirements described differ from those previously reported.
A Selective Medium for the Isolation of Agrobacterium Species
Authors: Clark A. G.
Published: March 2008

A defined salts medium containing lactose and MnSO4 as selective agents is described. This medium inhibits nearly all organisms of the soil microflora except Agrobacterium spp. against which it has no repressive or mutagenic effect. By using a modified test for 3‐ketolactose production together with plant inoculation, qualitative and quantitative assays for agrobacteria are possible.
Peat Culture of Rhizobium trifolii: an Examination by Electron Microscopy
Authors: Dart P. J. , Roughley R. J. , Chandler Muriel R.
Published: March 2008

Peat cultures of Rhizobium trifolii strain TA1 were examined by electron microscopy of thin sections of aldehyde‐OsO4 fixed Araldite embedded particles, and scanning reflection electron microscopy of the peat particle surfaces. The Badenoch peat used showed plant cell wall fragments; membranes with dense‐light‐dense appearance in vesicular or linear form; tubular structures; other unidentified wall‐like fragments, all usually surrounded by a matrix of varying electron density and granularity. The general level of electron density was high, even in plant wall fragments, although some electron‐transparent spaces were present in the matrix. Remains of bacteria and actinomycetes were often found within the peat particles. Particle shape varied a great deal; the surface was irregular with many crevices. Rhizobium cells were found on the surfaces, and sometimes in crevices of the particles. Rarely > 10 cells were found together and the cells were usually several μm apart. The rhizobia were structurally similar to broth cultured log phase cells, but often the region between cell wall membrane and plasma membrane was very electron dense. The rhizobia were usually enmeshed in a fibrillar matrix connecting them to the peat particles; this was probably the film seen to cover the bacteria in scanning surface pictures.
On the Growth and Survival of Clostridium septicum in Soil
Authors: Garcia M. M. , McKay K. A.
Published: March 2008

Clostridium septicum was inoculated into soils treated in different ways and samples were removed periodically for microbial analyses by one or more of the following methods: plate counts, fluorescent antibody staining, dehydrogenase activity and manometric techniques. Mass sporulation of the vegetative cells was not triggered initially when inoculated into amended soils. Moreover, the vegetative forms persisted in both sterile and unsterile soils for up to 30 days in incubated samples. Glucose, pyruvate, peptone and manure enhanced the growth and metabolic activity of Cl. septicum in soil. Wyoming bentonite tended to decrease dehydrogenase activity whereas Georgia kaolinite had no detectable effect. The significance of organic matter addition and type of clay mineral on the ecology of Cl. septicum is discussed.
Physiological and Morphological Characteristics of Kurthia zopfii Isolated from Meat Products
Authors: Gardner G. A.
Published: March 2008

Kurthia zopfii was frequently isolated from meats, especially comminuted meats. Its proportion of the aerobic flora in such products at the point of production did not generally exceed 10%. It is not known to cause spoilage of refrigerated meats, but there is some evidence to suggest that its presence in the flora is indicative of high temperatures during the production, distribution, etc., of the product. Morphological and physiological characteristics of K. zopfii were examined, and it was found that the species could be divided into two distinct groups. There was no association between the group and the product from which it was isolated.
A Rapid Method for Lyophilizing Streptomyces Cultures
Authors: Hopwood D. A. , Ferguson Helen M.
Published: March 2008

A quick single stage drying procedure for Streptomyces cultures using filter paper wicks soaked in crude culture suspensions is described.
An Automatic Inoculation Device for Seeding Bacterial Cultures
Authors: Andrew M. H. E. , Westwood N.
Published: March 2008

An automatic inoculation device which seeds a medium with a small inoculum of cells is described. It allows a culture to reach a particular stage of development at a predetermined time.
Lysis of Bacterial Spores with Hydrogen Peroxide
Authors: King W. L. , Gould G. W.
Published: March 2008

Spores of Bacillus cereus were made sensitive to lysis with H2O2 by treatment with reagents which break disulphide bonds (e.g. thioglycollic acid), by incubation with reagents which break hydrogen bonds (e.g. urea and lithium bromide) or by incubation at high temperatures. However, treated spores lost viability in the presence of H2O2 at the same rate as did untreated spores. Lysis was optimal at high pH values and in the presence of metal ions, e.g. Cu2+, suggesting that lysis was caused by free radicals formed by metal catalysed decomposition of the peroxide. Isolated spore coats, in contrast to whole spores, were lysed by H2O2 even when not pretreated. and the immediate products of spore coat lysis were soluble proteins; on continued incubation with H2O2 these proteins were degraded to low MW peptides and amino acids. It appeared that whole spores resisted lysis because peroxide sensitive bonds were masked by compact tertiary molecular structures, and that the sensitizing agents were able to loosen these structures sufficiently to expose bonds sensitive to H2O2.
Fine Structure of Methane‐utilizing Bacteria
Authors: Proctor Heather M. , Norris J. R. , Ribbons D. W.
Published: March 2008

Thin sections of methane‐utilizing bacteria have been examined in the electron microscope and the fine structure of the cells is described for the first time. The outstanding feature of all the isolates studied is the existence of intracellular membrane structures resembling those seen in nitrifying and photosynthetic bacteria. The possible significance of these membranes is discussed.
Trace Elements and Reproduction of Leptospirae
Authors: Burger G. , Fuchs G. H. P.
Published: March 2008

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 speeies. The addition of 0·2 × 10−6 gof Zn(NO3)2. 6H2O and 10−9 gofCoSO4. 7H2O/ml of Korthof's medium is recommended. Saprophytic leptospirae grow better with 10−6g of CoSO4. 5H2O/ml of medium.
Viability of Clostridial Spores and the Requirements of Damaged Organisms
Authors: Futter B. V. , Richardson G.
Published: March 2008

Viable counts of spores surviving exposure to bactericidal influences were higher in nitrogen than in hydrogen. The relationship between the nitrogen and hydrogen counts was dependent on the bactericidal pretreatment. Two species showed a cysteine dependence which was probably not due to its effect on Eh. Low concentrations of carbon dioxide caused a reduction in count.
Tetrad‐forming Cocci in Ciders
Authors: Carr J. G.
Published: March 2008

A tetrad‐forming coccus isolated from a ropy cider was characterized and identified with Pediococcus cerevisiae. This organism occurs both as a slime‐forming and non‐slime‐forming strain, the former being of considerable economic importance if it grows in stored cider. Some factors affecting slime formation have been investigated and are herein reported. The question of whether the generic names Pediococcus and Streptococcus should be merged is also discussed.
Aspects of the Action of Glutaraldehyde on Escherichia coli
Authors: Munton T. J. , Russell A. D.
Published: March 2008

Glutaraldehyde did not cause lysis of spheroplasts of Escherichia coli or of protoplasts of Bacillus megaterium. Its bactericidal activity against E. coli was potentiated in the presence of sodium bicarbonate or alkaline phosphate buffer. Over long periods, the uptake of aldehyde by E. coli increased when sodium bicarbonate was present. Glutaraldehyde with, but not without, sodium bicarbonate produced with E. coli cells a red colouration which was associated with the cell wall.
Oxytetracycline‐Glucose‐Yeast Extract Agar for Selective Enumeration of Moulds and Yeasts in Foods and Clinical Material
Authors: Mossel D. A. A. , Kleynen‐Semmeling A. M. C. , Vincentie H. M. , Beerens H. , Catsaras M.
Published: March 2008

The oxytetracycline‐glucose‐yeast extract agar of Mossel, Visser & Mengerink (1962) for the selective enumeration of moulds and yeasts in foods has been extensively tested on 4000 samples of various materials in two food microbiology and one clinical laboratory. Its performance was excellent in that it suppressed entirely the growth of Bacillaceae. Only when examining stools from patients under tetracycline therapy did the medium insufficiently inhibit Enterobacteriaceae. Substitution of oxytetracycline by 50 μg/ml of gentamicin was useful in such instances.
Pseudomonas viridiflava (Burkholder, 1930; Clara 1934)
Authors: Billing Eve
Published: March 2008

The characteristics of 12 isolates from 7 different hosts which were believed to be Pseudomonas viridiflava were studied using a variety of cultural and biochemical tests; in nutritional tests, 135 compounds were screened for their ability to serve as sole carbon and energy (C/E) sources. All cultures were similar in character and resembled closely Burkholder's original isolates: they were distinguishable from 13 cultures of other phytopathogenic Pseudomonas spp. Although they closely resembled Ps. syringae, they could be distinguished by their ability to rot potato, to utilize d(—) tartrate as sole C/E source and by their failure to utilize sucrose and to form levan on 5% sucrose nutrient agar. Pseudomonas viridiflava is a common epiphyte at least on dwarf beans (Scarlett, 1968) though it has rarely been cited as a cause of disease in Phaseolus spp. Results of lesion tests in dwarf bean pods and in the tobacco hypersensitivity test together with pectolytic activity strongly suggest however that it is a potential pathogen.
The Effect of Hibernation on the Caecal Flora of the Thirteen‐lined Ground Squirrel (Citellus tridecemlineatus)
Authors: Barnes Ella M. , Burton Glenna C.
Published: March 2008

The effect of hibernation on the caecal flora of the thirteen‐lined ground squirrel (Citellus tridecemlineatus) was determined by comparing the flora of 7 active squirrels with that of 6 × 6 days hibernators and 2 × 42 days hibernators. Direct microscopical examination showed the presence of a wide variety of micro‐organisms, including protozoa in all the animals. Using strict anaerobic techniques it was possible to isolate > 60% of the total flora of the active squirrels but only c. 30% in the hibernators. Several distinct types of anaerobic Gram negative, nonsporing rods predominated in both the active and hibernating animals. Gram positive, nonsporing rods and coccobacilli were present in the active squirrels but were not isolated from the 42 days hibernators. Atypical lactobacilli present at 106–108/g formed the major part of the aerobic flora of the active squirrels but were reduced at least 100‐fold during hibernation.
The Effect of Water Activity on the Heat Resistance of Heat Sensitive and Heat Resistant Strains of Salmonellae
Authors: Baird‐Parker A. C. , Boothroyd Margery , Jones E.
Published: March 2008

A strain of Salmonella senftenberg and a strain of Salm. bedford have been found with D60° values similar to that of the classical heat resistant salmonella, Salm. senftenberg strain 775W. The resistances of the two heat resistant serotypes and two heat sensitive strains of these serotypes was determined in heart infusion broth containing increasing amounts of sucrose, sodium chloride or glycerol. The observed changes in heat resistance could not be related directly to the aw of the heating menstruum. It is impossible to predict from such studies the heat resistance of salmonellae in foods of low aw.
Aerobic Bacterial Flora of the Bahama Bank
Authors: McCallum May F.
Published: March 2008

Examination of 225 cultures of bacteria from sediment on the Bahama Bank showed that the majority were Gram negative rods of the genera Vibrio and Pseudomonas. There is a possibility that the bacterial flora may be correlated with diagenesis of sediments and emergence from the marine environment.
Total Counts of Bacillus megaterium and Clostridium butyricum Spore Suspensions using a Microlitre Syringe
Authors: Marshall Anne C. , Rigby G. J.
Published: March 2008

A method for making total counts based on counting every organism in a small accurately measured volume of a suspension, using the microlitre syringe and phase contrast microscopy, has been described. Total counts of a Bacillus megaterium and a Clostridium butyricum spore suspension made by this method have been compared with haemocytometer chamber counts. The syringe method, although tedious, has the advantage that extraneous particles are easily identified. In certain circumstances a total and a colony count can be done on the same suspension using the syringe to deliver the same volume for both counts. The low percentage colony counts of many spore suspensions are probably not related to errors in the total counts, nor to manipulative errors in the colony counts, but are more probably related to the composition of the medium used for the colony counts.
The Precipitation of Calcium Carbonate from Seawater by Bacteria Isolated from Bahama Bank Sediments
Authors: McCallum May F. , Guhathakurta Kishwar
Published: March 2008

Precipitation of calcium carbonate by marine isolates from Bahamian sediments was studied in several media and under different experimental conditions. Almost all cultures brought about precipitation of aragonite crystals. The role of bacteria in the precipitation of CaCO3 in the marine environment is discussed.
Ultrasonic Dispersal of Activated Sludge Floes
Authors: Williams A. R. , Stafford D. A. , Callely A. G. , Hughes D. E.
Published: March 2008

A novel device which could be used for the disruption of activated sludge flocs, using a transversely oscillating wire, is discussed. The acoustic microstreaming generated around the wire produced hydrodynamic shear forces sufficiently strong to break up sludge flocs, without causing a loss in viability of the component cells. A 20‐fold increase in total heterotrophs and Thiobacillus‐type organisms was observed. Electron micrographs provided visual evidence for the disruption of flocs.
A Note on the Development of Resistance to Heat and Gamma Radiation in Salmonella
Authors: Corry Janet E. L. , Roberts T. A.
Published: March 2008

Repeated heat treatment and subculture increased the heat resistance of one strain of Salmonella typhimurium with no apparent increase in pathogenicity, or significant change in common biochemical characters. Cycling to γ radiation produced similar results. Re‐cycled strains contained extremely low proportions of the smooth colonies required for serological and phage typing.
Adenosinetriphosphate (ATP) Levels in Foods Contaminated by Bacteria
Authors: Sharpe A. N. , Woodrow M. N. , Jackson A. K.
Published: March 2008

ATP levels were determined in micro‐organisms and in foods, either as purchased or after incubation or addition of living bacteria. ATP levels in foods were divided into intrinsic ATP (derived from the original tissue) and microbial ATP. Intrinsic ATP decreased during incubation while bacterial ATP increased. At sufficiently high levels of contamination ATP levels could be related to bacterial concentrations.
A Novel Selective Method for the Production of Bacillus subtilis var. niger Spores
Authors: Evans C. G. T. , Harris‐Smith R.
Published: March 2008

A method for the recurrent selective production of heat resistant spores of Bacillus subtilis var. niger is described. The method embodies some features of both batch and continuous culture, permitting a daily production of 10 1 volumes of culture containing up to 2·3 × 1010 spores/ml. These spores are stable in storage at −20° and yet germinate readily, giving rise to easily recognizable, pigmented colonies.
The Microbial Associations in British Fresh Sausages
Authors: Dowdell Marilyn J. , Board R. G.
Published: March 2008

British fresh sausages, both pork and beef, contain climax populations consisting of Microbacterium thermosphactum, yeasts, lactobacilli and micrococci. The multiplication of lactobacilli and micrococci is a feature of sausages held at room temperature. The rate of growth of the other organisms decreased as the temperature of storage was lowered. The extent of growth of M. thermosphactum was inversely related to the initial load of contaminants of freshly prepared sausage meat. The yeasts appeared to be an independent component of the microbial associations. The growth of lactobacilli was favoured by a heavy initial infection of sausage meat. With the exception of lactobacilli, organisms situated at the surface of the sausage grew more quickly and formed larger populations than those at the centre; the lactobacilli formed populations of about the same size at both locations. There was a slow decrease in pH value (pH 6.8–7.0 to 6.2–6.0) of sausage meat as the microbial associations developed.
The Leakage of Cations and Amino Acids from Staphylococcus aureus exposed to Moist Heat, Phenol and Dinitrophenol
Authors: Allwood M. C. , Hugo W. B.
Published: March 2008

The leakage of K+, Na+ and amino acids from Staphylococcus aureus in an aqueous solution was studied at temperatures between 37 and 60°. The rate of efflux of K+ was temperature dependent. Above 50° an initial rapid loss of K+ was followed by a secondary and more prolonged period of efflux. 2.4‐Dinitrophenol enhanced the initial loss of K+, but not of amino acid, at all temperatures studied. Phenol, at a concentration which did not influence leakage at 37°, caused an increase in the K+ and amino acid losses at high temperatures. It also increased inactivation rates of the organism at all temperatures studied, while dinitrophenol was lethal only at lower temperatures. The importance of leakage to thermally‐induced inactivation of Staph. aureus is discussed.
Observations on the Microflora of Vacuum Packed Sliced Cooked Meat Products
Authors: Mol J. H. H. , Hietbrink Jacqueline E. A. , Mollen Henny W. M. , VAN Tinteren J.
Published: March 2008

Bacterial contamination of vacuum packed sliced cooked meats occurred mainly on the slicing and packaging line. Various types of these products were examined after packing, after 1 week storage at 8° and near the end of their shelf life. From products of 2 brands sampled at the retailer 153 cultures were isolated and identified. The relative growth rates of most of these strains were determined at 8 and 20°. Unclassified strepto‐bacteria constitute the most important component of the microflora of vacuum packed cooked meats. With a number of strains, growth experiments in vacuum packed sliced berliner sausage were made to study the effects of temperature, % of brine, pH and nitrite. The shelf life of vacuum packed sliced cooked meats would be improved if contamination with unclassified streptobacteria could be prevented. This presumably can be achieved if cooked meats were handled and sliced in an area strictly separated from raw cured meats.
Response of Spores and Vegetative Cells of Bacillus spp. in a Hydrocarbon‐Water System
Authors: Felix J. A. , Cooney J. J.
Published: March 2008

Nine strains of Bacillus spp. isolated from hydrocarbon fuel systems were examined for their ability to survive, multiply, sporulate and germinate in the aqueous phase of a hydrocarbon fuel‐aqueous salts medium. Vegetative cells did not survive in significant numbers. Larger inocula of vegetative cells survived better than smaller ones, suggesting that lytic products influenced survival. One isolate produced limited numbers of spores in the fuel‐salts system. Spores survived, and germinated at a slow rate. Germinated spores were capable of outgrowth and limited cell division. Thus, many Bacillus spp. isolated from fuel systems may be the progeny of spores which survived, rather than of cells proliferated or sporulated in the system. Survival patterns did not change when products of a hydrocarbon‐using bacterium were present in the medium. The data are consistent with the hypothesis that Bacillus spp. although isolated frequently from hydrocarbon systems, do not play a significant role in the ecology of such systems.
The Microbial Flora of the Rumen of Cows Fed Hay and High Cereal Rations and its Relationship to the Rumen Fermentation
Authors: Latham M. J. , Sharpe M. Elisabeth , Sutton J. D.
Published: March 2008

The rumen microbial population associated with feeding cows 3 rations, hay alone, 20% hay/80% flaked maize and 20% hay/80% rolled barley has been examined. The differences between the hay and the cereal rations were considerable but between the cereal rations only slight. Both cereal rations provoked & large drop in the proportion of butyrivibrios, and a rise in the proportion of selenomonads, peptostreptococci, lactobacilli and bifidobacteria. The importance of these and other changes occurring in the microbial flora are discussed in relation to their possible effect on the products of the rumen fermentation.
Kinetics of Action of Nystatin on Yeast
Authors: Patel P. V. , Johnston J. B.
Published: March 2008

Survival curves were obtained for related haploid, diploid and tetraploid strains of Saccharomyces cerevisiae, a pathogenic strain of Candida albicans and a nystatin‐resistant isolate of this strain, on exposure to a range of concentrations of nystatin. Susceptibility to nystatin decreased with increasing ploidy and was greater for Saccharomyces strains than for C. albicans strains. Death of cells was initially approximately logarithmic, but at certain concentrations some cells survived and cultures showed a subsequent growth phase.
Transport and Storage of Faeces for Bacteriological Examination
Authors: Crowther J. S.
Published: March 2008

The survival of bacteria in specimens of human faeces transported and stored at different temperatures was examined quantitatively. No significant losses of bacteroides, bifidobacteria, viridans streptococci, Streptococcus salivarius, enterococci, enterobacteria, and clostridia were observed when 10% (w/v) suspensions of faeces in broth containing 10% (v/v) of glycerol were frozen for one month at −25, −78 or −196°; lactobacilli showed significant losses at −196°; veillonellae showed significant losses at −25°. At −12° veillonellae and enterobacteria showed significant losses. Most bacteria survived well for 24 h in undiluted faeces sent by post.
The Effects of Bile Salts Media and the Age of Inocula in Quantitative Studies of Populations of Erwinia carotovora var. carotovora and E. carotovora var. atroseptica
Authors: Pérombelon M. C. M. , Lowe R.
Published: March 2008

Growth of Erwinia carotovora var. carotovora and E. carotovora var. atroseptica was significantly increased when bile salts were omitted from Logan's and Stewart's media. The lag and stationary phases were most, and the exponential phase was least, affected by bile salts which inhibited isolates of E. carotovora var. atroseptica more than those of E. carotovora var. carotovora. Selective media containing bile salts are therefore not suitable for enumerating populations of these organisms in soils or plant material.
Characterization of Nonfermentative Nonfastidious Gram Negative Bacteria encountered in Medical Bacteriology
Authors: Gilardi G. L.
Published: March 2008

More than 90 morphological and physiological characters of 546 strains of nonfermentative, nonfastidious, Gram negative bacteria isolated from clinical specimens were examined to determine those features most useful for the identification of these bacteria. The species examined included Moraxella osloensis, Mor. lacunata, Acinetobacter anitratum, Ac. haemolyticus subsp. haemolyticus, Ac. haemolyticus subsp. alcaligenes, Ac. Iwoffi, Alcaligenes faecalis, Alc. odorans var. viridans, Pseudomonas fluorescens, Ps. putida, Ps. pseudomallei, Ps. maltophilia, Ps. stutzeri, Ps. acidovorans, Ps. alcaligenes, and atypical strains of Ps. aeruginosa.
Trace Elements for Growth and Bulbiformin Production by Bacillus subtilis
Authors: Mahmood M.
Published: March 2008

Summary: The elements Mn and Fe, both alone and together, had a marked effect on growth and bulbiformin production by Bacillus subtilis. Copper, with Fe and/or Mn had a deleterious effect on antibiotic production, whereas Cu+Zn as well as Mo+B slightly increased the antibiotic produced over that obtained with Fe+Mn. The optimum requirement of Fe was 20 p/m for both growth and antibiotic activity. The requirement of Mn for maximum growth was higher (2 p/m) than that for antibiotic activity (1 p/m).
The Mechanism of Microbiological Leaker Spoilage of Canned Foods: A Review
Authors: Put Henriette M. C. , van Doren H. , Warner W. R. , Kruiswijk J. Th.
Published: March 2008

Summary: This review summarizes the work on the subject carried out mainly in the authors’laboratories but also in the associated laboratories of Metal Box Co. Ltd., London, and Plat Manufaktor, Malmö, Sweden. Special attention is paid to the mechanism of bacterial reinfection and how it is influenced by deviations in can construction or can handling procedures. Methods of preventing bacterial reinfection at the most critical points in the canning operation are considered and certain guiding principles are derived.
Radiation Sterilization: Microbiological Findings from Subprocess Dose Treatment of Disposable Plastic Syringes
Authors: Ley F. J. , Winsley B. , Harbord P. , Keall A. , Summers T.
Published: March 2008

Summary: Disposable plastic hypodermic syringes were taken weekly from commercial production, immediately prior to radiation sterilization, at each of 3 firms. They were irradiated at doses less than that used for sterilization, either with electrons or gamma rays, and tested for sterility. The relationship between the dose applied and the resulting proportion of syringes positive was similar for each firm. Amongst the organisms surviving subnormal process doses was a yeast of unusually high radiation resistance. The possibility of establishing a microbiological quality control procedure based on the routine use of a subprocess dose technique is discussed.
An Evaluation of the Gaspak System in the Culture of Anaerobic Bacteria
Authors: Collee J. G. , Watt B. , Fowler Elizabeth B. , Brown R.
Published: March 2008

Summary: Comparable results were obtained with a commercially available disposable system for the production of H2 and CO2 in an anaerobic jar (the Gaspak system) and with a standard anaerobic jar procedure. Both systems were used with the Baird & Tatlock anaerobic jar and a room temperature catalyst. The test organisms included strict anaerobes such as Clostridium oedematiens type D and Cl. tetani. Comparative tests were also made with Bacteroides species from laboratory stock cultures and with freshly isolated strains of Bacteroides. On occasion, higher recoveries were obtained with the standard system when relatively demanding models were set up but it has limitations, having been developed initially for research purposes. The Gaspak system probably gives more reliable and more reproducible results in a laboratory in which experience with strict anaerobes is limited or sporadic.
Mutation of the Methane Oxidizing Bacterium, Methylococcus capsulatus
Authors: Harwood J. H. , Williams E. , Bainbridge B. W.
Published: March 2008

Summary: Spontaneous mutants of Methylococcus capsulatus resistant to antibiotics, amino acid analogues and other compounds were obtained at frequencies similar to those found in other bacteria. Attempts to increase these frequencies with the mutagens N‐methyl‐N′‐nitro‐N‐nitrosoguanidine, N‐nitroso‐N‐methyl urethane, ethyl methane‐sulphonate and UV were unsuccessful. Using these mutagens, only one auxotrophic mutant was isolated from 11,082 colonies examined. The growth characteristics of this p‐aminobenzoic acid requiring mutant are described.
Collagenolytic Activity of Cured Hide Bacteria
Authors: Woods D. R. , Welton R. L. , Thomson Jennifer A. , Cooper D. R.
Published: March 2008

Summary: The aerobic and anaerobic collagenolytic activities of bacterial populations from 1 Australian and 2 South African cured hide samples at 0·85, 2·34, 7·0 and 10·0% of NaCl are described. The rate of denaturation of pure, undegraded collagen was determined by the release of amino acids and considerable collagenolysis was demonstrated. Collagenolytic activity was highest under aerobic conditions. Australian hides which produce uniformly good leather with little or no decay lacked collagenolytic bacteria.
Growth and Cellulase Formation by Cellvibrio fulvus
Authors: Berg B. , Hofsten B. v. , Pettersson G.
Published: March 2008

Summary: The aerobic cellulolytic bacterium Cellvibrio fulvus grew on several sugars and polysaccharides, but not on highly substituted cellulose derivatives, organic acids and alcohols. Whereas no growth was obtained on long cotton fibres, it occurred on such fibres cut into small pieces, and on filter paper and chromatography powders derived from cotton. Lignin free wood pulp was rapidly degraded. The organism grew best at pH 7–8 and utilized nitrate, ammonium and some amino acids as nitrogen sources. The bacteria have cell‐bound cellulase but enzyme was also found in the culture medium. Glucose repressed cellulase formation and the enzyme activity of cultures grown on cellulose was much higher than on sugars. Reducing sugar was not detected in cellulose cultures. The pH optimum for hydrolysis of carboxymethylcellulose (CMC) was 7 and the enzyme was inhibited by mercuric acetate but not by p‐chloromercuribenzoate or EDTA. Fractionation of cellulase preparations from cultures grown on partially hydrolysed filter paper gave many components of different molecular weights. The activities of these components against carboxymethylcellulose and microcrystalline cellulose differed.
Biological Control of Crown Gall: Field Measurements and Glasshouse Experiments
Authors: New P. B. , Kerr A.
Published: March 2008

Summary: An ecological study showed that the pathogeniec form of Agrobacterium radiobacter (A.r. var. tumefaciens), biotype 2 was present in soil near galled almond seedlings, where it formed a significant proportion of the total biotype 2 population; the pathogen was not detected near healthy plants. One nonpathogenic biotype 2 isolate was able, when present in numbers approximately equal to the pathogen, to prevent crown gall induction in tomato and peach seedlings. This isolate gave complete biological control of crown gall in a glasshouse test. Six other nonpathogenic isolates did not significantly inhibit gall induction by equal numbers of the pathogen. In the field, gall induction probably depends on the size of the population of the pathogen (both absolutely and relative to that of the nonpathogen) at a wound site and on the inhibitory efficiency of the nonpathogen.
The Relationship between the Intestinal Microflora and the Effects of Diets containing Raw Navy Beans (Phaseolus vulgaris) on the Growth of Japanese Quail (Coturnix coturnix japonica)
Authors: Jayne‐Williams D. J. , Hewitt D.
Published: March 2008

Summary: Japanese quail chicks died within a few days when fed diet containing raw navy beans, whereas a similar diet containing autoclaved beans supported normal growth. The diet containing raw beans was nonlethal to germfree quail chicks, but did not support such good growth as the heated bean diet. The effects of associating germfree quail on the raw bean diet with various combinations of 149 pure cultures of bacteria isolated from the intestines of ordinary quail have been studied. Strains of Escherichia coli were shown to be responsible for the lethal effects of the raw bean diet.
Influence of Some Preservatives on the Quality of Prepacked Cod Fillets in Relation to the Oxygen Permeability of the Film
Authors: Debevere J. M. , Voets J. P.
Published: March 2008

Summary: The deterioration of prepacked cod fillets in relation to different concentrations of citric acid (HC) and of potassium sorbate (PS) was studied bacteriologically and chemically. Spoilage of fish treated with PS in relation to the oxygen permeability (OP) of the polyethylene film was also examined. The trimethylamine (TMA) and formalin bound nitrogen compounds (FBN) formation at 0° in prepacked cod fillets is inhibited by the addition of HC and PS. A concentration of 0·4% of PS in the cod fillets is sufficient to inhibit the TMA production completely. The OP of the film determines the keeping quality of the cod fillets containing 0·4% of PS. The film with the lowest OP gives the best results, since the spoilage of PS treated fish during the first 12 days is exclusively caused by an increase of FBN. The formation of this fraction at 0° is related directly to the OP of the packing film. From the experiments with PS treated cod fillets it can be deduced that a film with a low OP gives the best results.
A Waterborne Actinomycete Resembling Strains Causing Mycetoma
Authors: Lawson Ellen N. , Davey Lorna M.
Published: March 2008

Summary: An actinomycete, closely resembling strains of Actinomadura madurae causing mycetoma, was isolated from a stream in South Africa. The organism was present in all water samples collected monthly for a year. It is considered to be indigenous in the stream because its population density was not influenced by water run‐off from the soil into the stream or by organic pollution.
A Survey of the Occurrence of Vibrio parahaemolyticus and V. alginolyticus on Mussels and Oysters and in Estuarine Waters in the Netherlands
Authors: Kampelmacher E. H. , van Noorle Jansen Lucretia M. , Mossel D. A. A. , Groen Frieda J.
Published: March 2008

Summary: In a survey on the occurrence of Vibrio parahaemolyticus and V. alginolyticus on mussels and oysters and in estuarine waters in The Netherlands it appeared necessary to use at least 2 different enrichment procedures as well as isolation methods in parallel to obtain reliable results. A consistent identification of V. parahaemolyticus on biochemical grounds remains a difficult task; further research in this area is definitely required. The ligated intestinal segment technique gave inconsistent results; injection of organisms into the yolk sac of fertilized hen eggs seems to be a more reliable diagnostic procedure. Of 288 samples of mussels examined 2·4% were V. parahaemolyticus positive, 80 samples of oysters were all negative and amongst 64 water samples 4·7% were positive. V. alginolyticus was isolated in similar percentages of samples of mussels and water, but oysters were positive to an extent of 6·8%.
A Comparison of Methods for the Enrichment of Salmonellae from Sheep Faeces
Authors: Grau F. H. , Smith M. G.
Published: March 2008

Summary: A 10‐tube MPN technique was used to test the efficiency of nutrient, tetrathionate, mannitol‐selenite and mannitol‐selenite‐cystine broths as enrichment media for detecting salmonellae. Small numbers of broth grown salmonellae could be detected in all 4 media in the presence of 5% of sheep faeces. In naturally infected sheep faeces small numbers of salmonellae were not detected with either nutrient or tetrathionate broths. With mannitol‐selenite the sensitivity of salmonella detection increased with both incubation temperature (37–43°) and the addition of faeces. The most sensitive and reliable medium for detecting salmonellae in naturally infected sheep faeces was mannitol‐selenite‐cystine broth. Neither incubation temperature (37–43°) nor the addition of faeces had a statistically significant effect on its sensitivity.
Starch Gel Electrophoresis of Catalase and Esterase Isoenzymes from Some Rhizobium and Agrobacterium spp.
Authors: Clark A. G.
Published: March 2008

Summary: The esterase and catalase isoenzymes of Agrobacterium tumefaciens and A. radiobacter have been compared to those of the fast growing rhizobia using starch gel electrophoresis. An overall similarity was found for the agrobacteria‐rhizobia group although the majority of the agrobacteria possessed only one catalase. Those agro‐bacteria with 2 catalases gave patterns similar to Rhizobium meliloti and were 3‐ketolactose negative. Agrobacterium pseudotsugi isoenzymes, although fitting the general agrobacteria‐rhizobia pattern, were not identical to any specific isogram. The taxonomic value of these findings is discussed.
Some Growth Characteristics of a Hyphomicrobium sp. in Batch Culture
Authors: Wilkinson T. G. , Hamer G.
Published: March 2008

Summary: A Hyphomicrobium sp. isolated from a mixed culture of methane utilizing micro‐organisms grew rapidly with generation times as short as 4·7 h in pure culture with methanol as the carbon substrate. The stoichiometry of oxygen utilization by this micro‐organism, as indicated by the cell yield with respect to oxygen varied at low levels of dissolved oxygen in the culture medium. In addition, the initial methanol concentration in the medium affected the maximum specific growth rate of the Hyphomicrobium sp.
Quantitative Aspects of Growth of the Methane Oxidizing Bacterium Methylococcus capsulatus on Methane in Shake Flask and Continuous Chemostat Culture
Authors: Harwood J. H. , Pirt S. J.
Published: March 2008

Summary: Experiments were directed towards the production of high biomass concentrations in cultures of Methylococcus capsulatus. In shake flasks the effects of ammonium ion, phosphate ion and various trace metals on growth were studied. In the chemostat the effects on growth of methane limitation, oxygen limitation, aeration, dilution rate, pH value and temperature were studied and carbon balances were made in steady state conditions. Growth in the fermenter was stimulated by the use of Amberlite CG–120 ion exchange resin in the medium. The probability that Amberlite removed a growth, inhibitor is discussed.
A Comparison of Various Selective Media, including a New Selective Medium for the Isolation of Brucellae from Milk
Authors: Farrell I. D. , Robertson L.
Published: March 2008

Summary: A comparative trial of a new medium for brucella was made on samples of milk from individual cows and herd samples of milk. The new medium gave a higher isolation rate than any of the other 3 selective media tested. There was no evidence that the new medium inhibited any of the biotypes of Brucella abortus, especially biotype 2; it was the only medium suitable for isolating from samples of herd milk strains of biotype 2 which are sensitive to antibiotics and aniline dyes.
Ethanol Production from Glucose by Torulopsis glabrata Occurring Naturally in the Stomachs of Newborn Animals
Authors: White R. W. , Lindsay D. B. , Ash R. W.
Published: March 2008

Summary: The elucidation of the mechanism of ethanol production in the stomachs of newborn animals is described. The condition was reproduced in lambs and piglets by feeding glucose in fat‐free milk, and shown to arise from fermentation by the naturally occurring yeast Torulopsis glabrata, which can reach population densities of 106 viable cells/ml of stomach contents. These yeasts ferment glucose, producing up to 500 mg of ethanol/100 ml of contents in the stomach, but do not ferment sucrose or lactose. High levels of ethanol in plasma of lambs are accompanied by obvious symptoms of intoxication. The characteristics of a constantly occurring coliform type bacterium, found at densities up to 108 viable cells/ml in association with the Torulopsis yeasts were examined. Its precise role is not clear.
New Culture Conditions for Clostridium histolyticum leading to Production of Collagenase of High Specific Activity
Authors: Takahashi S. , Seifter S.
Published: March 2008

Summary: New culture conditions are described for the growth of Clostridium histolyticum allowing for the production of collagenase (E.C.3.4.4.19) in a highly purified form, free of general protease activity. The conditions include the use of a mixture of sodium bisulphite‐oxidized sodium thioglycollate to provide the reducing environment within an otherwise standard culture medium. Also, new modifications in the preparation of collagenase A are reported.
Growth of Mycobacterium paraffinicum on Low Concentrations of Ethane in Soils
Authors: Brisbane P. G. , Ladd J. N.
Published: March 2008

Summary: Growth in soils of Mycobacterium paraffinicum with 0, 5, 15, 45 and 270 p/m of ethane was assayed by adding ethane‐1,2‐14C and measuring the 14CO2 produced. With < 45 p/m of ethane the lag period lasted several months. Differences in growth associated with different soils suggest that the microbial method of oil prospecting is unlikely to be commercially successful.
Factors which Influence the Enumeration of Bdellovibrio bacteriovorus in Sewage and River Water
Authors: Staples D. G. , Fry J. C.
Published: March 2008

Summary. A double layer plating technique was used for counting Bdellovibrio bacteriovorus in river water and sewage samples. The optimum conditions for enumeration were provided by dilute media with 0.6 % of agar as the top layer, incubated for 6 days at 30° with Achromobacter sp. as the host. Pretreatment of samples affected counts: centrifugation and membrane filtration reduced the bdellovibrio count, homogenization increased it. Protozoa in sewage samples caused large plaques that greatly hindered counting and attempts to eliminate these plaques were unsuccessful. The highest counts in sewage samples averaged 900 cells/ml.
The Metabolism of Amino Compounds by Some Gram Negative Yellow Pigmented Rods
Authors: McMeekin T. A. , Patterson J. T. , Stewart D. B. , Murray J. G.
Published: March 2008

Summary. The ability of 6 Gram negative, yellow pigmented rods to metabolize various amino compounds was investigated. The strains examined represented 3 groups of organisms of this type. The strains of 2 groups, O and S, had low G+C ratios while those of group Y had high G+C ratios. Strains of groups O and S dissimilated arginine by the dihydrolase pathway but the group Y organisms did not attack arginine. No decarb‐oxylase activity was recorded, but the ability to transaminate amino acids in the presence of added keto acids was demonstrated for all the strains examined. The pattern of amino acid degradation produced by strains of the low G+C groups was similar though distinct from that of the high G+C types. In the absence of added keto acids deamination was the main mode of attack on amino compounds.
A Comparison of the Distribution of Intestinal Bacteria in British and East African Water Sources
Authors: Evison Lilian M. , James A.
Published: March 2008

Summary. Various workers have suggested that there are marked regional variations in the distribution of intestinal bacteria used as indicators of pollution in water supplies. This paper presents the results of investigations into the distribution of some intestinal indicators (coliforms, *Escherichia coli, faecal streptococci and anaerobic lactobacilli) in water sources in the United Kingdom and in Kenya. The surveys showed that the differences in distribution were not significant except for some coliforms (Citrobacter and Klebsiella spp.), but that survival subsequent to excretion was affected by ambient temperature.
Design of a Temperature Gradient Incubator
Authors: Packer G. J. K. , Prentice G. A. , Clegg L. F. L.
Published: March 2008

Summary. A temperature gradient incubator heated and cooled by circulating liquids is described which is suitable for incubating micro‐organisms in liquid media and on solid media in roll tubes. The maximum deviation from a linear temperature gradient is 0·35% of the range (0·13°) even when used at temperatures up to 30° above ambient. The temperature of any set of sample wells is uniform to within 0·07° (3·5% of the difference between adjacent rows).
Relationships between Estimates of Binding of Antimicrobial Agents by Macromolecules, based on Physicochemical and Microbiological Data: Cetylpyridinium Chloride and Polyethylene Glycol
Authors: Coates D. , Richardson G.
Published: March 2008

Binding of cetylpyridinium chloride (CPC) to a nonionic, non‐surface active macromolecule, polyethylene glycol 20 M (PEG), has been investigated by equilibrium dialysis and a microbiological viable count technique. The results indicate that the bactericidal activity of CPC in aqueous solutions of the PEG cannot be simply equated with the activity of free aqueous CPC. The activity was found to be equal to or greater than that expected from the binding data depending on the CPC concentration. The implications of the experimental findings are discussed.
Comparison of Plating and Most Probable Number Techniques for the Isolation of Staphylococci from Foods
Authors: Patterson J. T.
Published: March 2008

The recovery of Staphylococcus aureus on a solid medium similar to that of Smith & Baird‐Parker (1964) was compared with the most probable number (MPN) of the organism in a range of foods, using the liquid medium of Giolitti & Cantoni (1966). The latter proved more efficient in detecting staphylococci in foods, particularly where low numbers were present.
The Affinity for Methane and Methanol of Mixed Cultures Grown on Methane in Continuous Culture
Authors: Wilkinson T. G. , Harrison D. E. F.
Published: March 2008

Pure cultures of Hyphomicrobium sp. had a high affinity for methanol (Km= 8·33 × 10−6 M) and the maximum respiration rate was c. 5 times higher than that of a mixed culture in which a methane‐utilizing pseudomonad predominated (Km= 2·94 × 10−2 M). From a comparison of the substrate affinities, a culture of the methane‐utilizing organism would be expected to produce levels of methanol high enough to inhibit methane oxidation and the Hyphomicrobium sp. would be able to scavenge this methanol.