bluuebunny/crossref_metadata_2025 huggingface dataset:
PHYSICOCHEMICAL PROPERTIES OF PHAGES FOR AGROBACTERIUM RADIOBACTER
Authors: Roslycky E. B. , Allen O. N. , McCoy Elizabeth
Published: February 2010

Plaques of phages PR-1001, PS-192, PR-590a, and PsR-1012 were clear, without halos, and with definite edges. Phage heads were approximately 60 mμ in diameter with short blunt tails. Phage titers in nutrient broth were stable during 452 days storage at 4 °C but were decreased considerably at 25 °C. After 46 days at 37 °C no surviving particles of any of the phages were detected. Ultraviolet inactivation of particles was not a first-order reaction. The pH stability range was between pH 7 and 11. Inactivation at 50 °C and 55 °C was least in saline, more marked in nutrient broth, and most severe in distilled water. Protection against inactivation was a function of the mono- and di-valent cation concentration. Separately the cations provided insignificant protection. NH4+ in combination with Ca++ or Mg++ inactivated phage particles as did also Cu++, Hg++, Al+++, and Fe+++ in solutions of NaCl. Heat-inactivated particles showed collapsed heads that indicated a loss in DNA.
MICROORGANISMS IN THE ROOT ZONE IN RELATION TO TEMPERATURE
Authors: Rouatt J. W. , Peterson E. A. , Katznelson H. , Henderson V. E.
Published: February 2010

A study was made of the numbers and kinds of microorganisms in the root zone of wheat and soybeans grown in the greenhouse at three ranges of temperature: 55–60°, 70–75°, and 85–90 °F. Numbers of bacteria in the rhizosphere and rhizoplane of wheat decreased as the temperature increased, whereas numbers in the root-free soil and on soybean roots increased with increased temperature. The same relationships held for methylene blue reducing, glucose-fermenting, and ammonifying bacteria and those requiring amino acids for optimal growth. Generic analysis of bacterial isolates showed that the percentage of Gram-negative rod-forming organisms increased with a rise in temperature in root-free soil and on soybean roots but decreased on wheat roots. On the other hand, the incidence of Gram-positive and pleomorphic organisms decreased in soil and on soybean roots with higher temperature and increased on wheat roots.Fungal isolations from washed root segments showed a greater incidence of Mucor, Rhizopus, Rhizoctonia, and Gliocladium on soybeans at the high temperature whereas species of Fusarium and Cylindrocarpon were more prevalent at the low temperature. With wheat the most striking feature was the predominance of non-sporing dark species at the high temperature and of non-sporing hyaline types at the low temperature.The number of soil nematodes decreased in the rhizospheres of both plants with increased temperature, the effect being more pronounced with soybeans. With this crop all except one of the genera recognized decreased in number, whereas with wheat, the incidence of certain nematodes such as species of Helicotylenchus, Boleodorus, and Aphelenchoides did not change with temperature.The results suggest that temperature exerts a direct effect on the microorganisms in the root zone and an indirect effect by influencing plant growth.
PROTEOLYTIC ACTIVITY OF SOME COLD-TOLERANT BACTERIA FROM ARCTIC SEDIMENTS
Authors: McDonald I. J. , Quadling C. , Chambers Alice K.
Published: February 2010

A number of Gram-negative cold-tolerant bacteria capable of growth on agar at 0 °C but not at 25 °C were isolated from Arctic littoral and marine sediment samples. Eight of these organisms able to hydrolyze gelatin were chosen for study. Taxonomically these organisms consisted of an unidentified but closely related group of seven cultures and a single Pseudomonas strain. Culture supernatants of these Arctic organisms contained proteinases that hydrolyzed gelatin, casein, and β-lactoglobulin, but not bovine plasma albumin. When casein was the substrate, the proteinases were most active at pH 7.0 to 8.0 between 30° and 40 °C and were inhibited by ethylenediaminetetraacetic acid. The proteinases were relatively heat-labile; the activity of the most heat-labile was reduced by 90% in 20–30 minutes at 40 °C and that of the most heat-stable by 90% in 45 minutes at 50 °C. Proteinases of the unnamed group of Arctic organisms were characterized by a low temperature characteristic and possession of high enzymic activity at low temperatures. Presumably such organisms can convert protein to simple nitrogenous compounds in the Arctic environment.
THE RECOVERY OF DIPHTHEROIDS FROML-TYPE ORGANISMS CONTAMINATING TISSUE CULTURES
Authors: Carter G. R. , Greig A. S.
Published: February 2010

Cultures of a number of tissue cell lines were observed to be infected with an organism of the kind usually referred to as PPLO. That the organism was in reality the L-form of a diphtheroid was demonstrated by the repeated recovery of the bacillary form from L-type colonies. The cultural procedure employed to recover the bacillary phase is described, and, as well, some of the characteristics of the L-type organisms and the diphtheroid. Attempts to eliminate the L-type organisms from tissue cultures by means of certain antibiotics and heat treatment were unsuccessful.
GLUTAMIC DEHYDROGENASE FROM UREDOSPORES OF PUCCINIA HELIANTHI SCHW.
Authors: Smith J. E.
Published: February 2010

Glutamic dehydrogenase was extracted from germinated uredospores of Puccinia helianthi and partially purified. The enzyme was specific for nicotinamide-adenine dinucleotide was inhibited by several metal-chelating agents and was shown to possess sulphydryl groups essential for activity.
RÉSISTANCE COMPARÉE DES VIRUS POLIOMYÉLITIQUE, HERPÉTIQUE, SPUMEUX ET SV-40 À L"ACIDITÉ
Authors: Dubreuil Robert , Chagnon André , Pavilanis Vytautas
Published: February 2010

Poliovirus suspensions of different types and strains, as well as vacuolating virus (SV-40) and human herpes virus, were adjusted to various points between pH 8.5 and pH 1.5. The comparative inactivation of these viruses was established for different conditions of temperature and time of treatment. There appeared to be a large enough difference in the resistance of the poliovirus group on the one hand and that of herpes and vacuolating virus on the other to permit a selective inactivation of these last-mentioned viruses in contaminated suspensions of poliovirus. A few assays done with foamy virus showed that this selective inactivation could be applied also to poliovirus suspensions contaminated with this agent.This simple technique could be of help in the preparation of poliomyelitis vaccine, live or inactivated.
SOME WAYS IN WHICH A PARAFFIN OIL IMPEDES APHID TRANSMISSION OF POTATO VIRUS Y
Authors: Bradley R. H. E.
Published: February 2010

In laboratory tests with a light white paraffin oil, transmission of potato virus Y by viruliferous adults of Myzus persicae (Sulz.) was impeded by (a) allowing aphids to probe on a leaf coated with oil, (b) manually touching the end of the labium to an oil-coated leaf, or (c) inserting the bare stylets directly into the oil. The first two of these but not the third also impeded for some minutes the uptake and transmission of virus Y by nonviruliferous aphids. Oil sprayed on plants kept in the laboratory continued to cause these effects for some weeks. If infected plants, used as virus sources for aphids, were coated with oil, transmission from them was impeded. It is still not clear why oil impedes transmission. But the results give good reasons to believe that oil can be used in the field to prevent spread of certain aphid-borne viruses.
FINE STRUCTURE OF MICROSCLEROTIA OF VERTICILLIUM ALBO-ATRUM REINKE & BERTH.
Authors: Nadakavukaren M. J.
Published: February 2010

The fine structure of microsclerotia of Verticillium albo-atrum Reinke & Berth. is described. Fixing and embedding procedures are given. Microsclerotial units are composed of thin- and thick-walled cells in close association with each other. The larger thick-walled cells contain different cytoplasmic inclusions and food vacuoles, while the smaller thin-walled cells contain nuclei or look empty. Only the thin-walled cells are found to germinate. The thick-walled cells, with their stored food, appear to serve a double role of protection of, and as a source of, food for the thin-walled cells.
EVIDENCE OF PHOSPHORYLASE ACTIVITY IN STYLONYCHIA PUSTULATA
Authors: Hunter Norvell W.
Published: February 2010

Qualitative and quantitative procedures were used to demonstrate phosphorylase activity in Stylonychia pustulata. The enzyme did not require divalent metal cations for activity; however, Mn2+, Ca2+, Co2+, and Zn3+enhanced the activity. The enzyme was inhibited by Sr2+, Ba2+, Ni2+, Cd2+, Fe2+, Sn2+, Hg2+, Pb2+, and Cu2+. The most effective inhibitor was Sr2+, which produced about 57% inhibition. The enzyme was more active at a pH of 6.2 than at a pH of 7.2, 8.2, or 9.2. The optimum temperature for activity was about 30°. The homogenates of the animals were found to contain 0.053 μg of glycogen/μg of protein N.The intracellular distribution of the enzyme in the animals could not be determined by the histochemical techniques used in these experiments.
PHYSIOLOGICAL AND NUTRITIONAL STUDIES OF A CONIDIAL STRAIN OF DRECHSLERA TERES (SACC.) SHOEMAKER AND A MYCELIAL VARIANT
Authors: Piening L. J.
Published: February 2010

A fluffy white mycelial variant of low pathogenicity developed from the normal sporulating pathogenic fungus Drechslera teres growing on P.D.A., V-8 agar, M.Y.A., and Czapek agar. Factors such as the amount and type of carbon and nitrogen compounds present influenced the production of the mycelial variant, which was less virulent than the original isolates.The two forms of this fungus differed in the amount of growth according to temperatures, pH values of the media, and nutritional conditions. The mycelial form arose more frequently in conidial cultures grown in media of a high sugar content. Growth of the conidial form was not so good as that of the mycelial form on media containing amino acids.There was some loss of pathogenicity of the conidial culture after it had been grown and transferred eight consecutive times on media containing methionine, cysteine, or asparagine. The pathogenicity of the mycelial form was unaltered regardless of its nutrition.Factors which lead to the development of the mycelial variant are discussed.
RELEASE OF ULTRAVIOLET-ABSORBING MATERIAL FROM ESCHERICHIA COLI AT SUBZERO TEMPERATURES
Authors: Lindeberg Gösta , Lode Aaslaug
Published: February 2010

When cells of Escherichia coli were suspended in dilute artificial seawater and cooled to various subzero temperatures, a maximum lethal effect occurred around −40 °C. In addition, rapid cooling to −26 °C of bacteria, suspended in concentrated, non-freezing seawater caused a pronounced decrease in viability ("cold shock"). The loss in viability was accompanied by a proportional release from the cells of ultraviolet-absorbing material and by an increase in the ribose and organic phosphorus contents of the suspending liquid. It seems possible that the released material, at least partly, consisted of nucleotides or nucleic acids.
APPLICATION OF IMMUNOFLUORESCENCE IN THE DIAGNOSIS OF INFLUENZA FROM THROAT WASHINGS
Authors: Baratawidjaja R. K. , Hewson Ann , Labzoffsky N. A.
Published: February 2010

Indirect immunofluorescent staining provides a valuable tool for the rapid diagnosis of influenza from throat washings. In 73 throat washings tested for the presence of Asian influenza virus by egg inoculation and by immunofluorescence, identical results were obtained by both methods. Although cross reactions were noted between strains within the type, the strain-specific reaction could be easily distinguished by a greater intensity of the fluorescence. The immunofluorescent technique has a great advantage over the isolation procedure since the results of the examination could be reported within 4–5 hours after arrival of the specimens in the laboratory. The technique is, of course, applicable only when a known type of influenza virus or a new strain antigenically related to the known strains is involved in the outbreak.
ROLE OF SUPERFICIAL STRUCTURES IN THE CHARACTERISTIC MORPHOLOGY OF LAMPROPEDIA HYALINA
Authors: Murray R. G. E.
Published: February 2010

A strain of Lampropedia hyalina (A.T.C.C. 11041) has lost the ability to form the tablets of cells and sheets. In fact, it has lost the characters that give it generic status and allow its identification. Detailed comparison with a sheeting strain of the species indicates that what is lost is an intercalated layer, which glues together the cells of the tablet, and the outermost of the two structured layers which form the surface envelope. Both of these elisions may be important to tablet formation but the former is probably the most important. There is evidence that these layers may still be retained on occasional cells as small islands of material in the appropriate anatomical regions. However, although these islands must reproduce and be perpetuated in the strain, there is no evidence that the layers can be fully recovered and no fully characteristic Lampropedia have been isolated from the mutilated strain.
A CHEMICALLY DEFINED MEDIUM FOR HALOBACTERIUM SALINARIUM STRAIN 1
Authors: Dundas Ian D. , Srinivasan V. R. , Halvorson H. Orin
Published: February 2010

A chemically defined medium has been composed for Halobacterium salinarium strain 1. The medium consists of inorganic salts, 10 amino acids (lysine, arginine, proline, valine, methionine, isoleucine, leucine, tyrosine, phenylalanine, and glutamine) and cytidylic acid. The amino acids valine, methionine, isoleucine, and leucine are found to be essential for growth in this medium. Growth rates in the synthetic medium are not as high as those obtained in complex media. The medium allows growth of several halophilic organisms.
STUDIES WITH STAPHYLOCOCCAL TOXINS: VII. SEPARATION OF A PROTEOLYTIC ENZYME FROM ALPHA HEMOLYSIN
Authors: Robinson J. , Thatcher F. S.
Published: February 2010

Certain preparations of alpha hemolysin induced dissolution of rabbit and sheep erythrocytes and hydrolyzed casein. Components which were independently hemolytic and proteolytic were separated by the following sequence of procedures: precipitation with zinc acetate and ethyl alcohol at approximately −5 °C and pH 4.0, ion exchange chromatography with carboxymethylcellulose, and zone electrophoresis with granules of potato starch. The comparative lytic activity of the hemolytic component against erythrocytes of the rabbit and of the sheep was 19:1. No separation could be effected between these two hemolytic properties.
EFFECTS OF SOME AMINO ACID ANALOGUES ON BACILLUS CEREUS SPORULATION USING STATIC AND SHAKEN CULTURES
Authors: Perkins John P. , Louie Daniel D. , Aronson John N.
Published: February 2010

The possible utility of static culture conditions for sporulation studies was evaluated. The effects of a series of potential amino acid antagonists on the growth and sporulation of a strain of Bacillus cereus in a defined medium were compared under both static and shaken culture conditions. A randomly picked series of 24 analogues was observed to produce all of the possible effects (no inhibition of growth or sporulation, inhibition of growth, inhibition of sporulation, delay of growth and sporulation) with no important qualitative differences between the shaken and static systems. The commonly accepted premise that shaken cultures must be used for sporulation studies has no general validity; the simpler technique of static culture may have great value for observation of the developmental stages of sporulation.
LYSOGENY IN A STRAIN OF XANTHOMONAS GAMPESTRIS
Authors: Sutton M. D. , Quadling C.
Published: February 2010

Fourteen bacterial strains representing eight so-called species of phytopathogenic xanthomonads were tested for lysogeny both before and after treatments known to induce phage development in lysogenic bacteria. Only a single temperate phage, of restricted host range, was found. Evidence suggestive of defective lysogeny was found in a number of cases.Strain P165, Xanthomonas campestris, when treated with antibiotic Mitomycin C at a concentration of 0.1,ug/ml in nutrient broth, produced phage particles active on strain P12S, X. campestris. No other sensitive strains were found among the 81 tested, representing 22 species of Xanthomonas. This phage (P165/P125) produced small turbid plaques, 0.6 mm to 0.8 mm in diameter, with indefinite margins. Evidence for the lysogenization of P125 strain by this phage was found. Clear plaques were sometimes found in lawns of lysogenized cells of P12S. These were presumably derived from phage mutants with increased virulence. When examined under the electron microscope, the phage particles were semispherical, approximately 65 m/x in diameter with rudimentary tails.
GLUCOSE INHIBITION OF ASPARTASE SYNTHESIS BY AEROBACTER AEROGENES
Authors: Farley Margaret A. , Lici-Istein Herman C.
Published: February 2010

Studies were made comparing aspartase synthesis by Aerobacter aerogents grown in the presence and in the absence of glucose, and with or without agitation. It was observed that when a sufficient initial glucose concentration was employed, enzyme synthesis was not resumed to maximum levels even after complete utilization of the sugar. At a lower glucose concentration, however, synthesis did occur, suggesting that the specific repressor metabolite(s) produced from the glucose was not accumulated to inhibitory concentrations after the sugar was metabolized. A difference between stationary and aerobic (shaken) cultures was noted, perhaps affording a suitable system for investigating the molecular mechanism of glucose repression.
A COMPARATIVE STUDY OF THE IMMUNE SERA OF ANIMALS IMMUNIZED WITH CLOSTRIDIUM PERFRINGENS TYPES C AND D
Authors: Habeeb A. F. S. A.
Published: February 2010

The Ouchterlony double-diffusion technique and immunoelectrophoresis were employed to study the immune sera of animals immunized with C. perfringens types C and D. The animals showed great variability in their response to injections of the antigens. Types C and D antisera gave 9 to 10 precipitin lines with their respective homologous antigens, a number which was greater than that reported by previous workers.
INTERACTION OF SEED-COAT MICROFLORA AND SOIL MICROORGANISMS AND ITS EFFECTS ON PRE- AND POST-EMERGENCE OF SOME CONIFER SEEDLINGS
Authors: Timonin M. I.
Published: February 2010

Analyses of seed samples of Pinus banksiana Lamb., P. contorta Dougl. var. latifolia Engelm., and Picea glauca (Moench) Voss demonstrated the presence of 12 genera of fungi. Pythium, Phytophthora, and Rhizoctonia were not isolated but typical symptoms of damping-off disease were observed among the seedlings grown in sterilized soil. Surface sterilization of seeds resulted in a significant reduction in emergence of P. banksiana and P. glauca seedlings but not on P. contorta var. latifolia. The cause of this difference is discussed. The post-emergence mortality of P. banksiana seedlings resulting from surface-sterilized seeds grown in sterilized and unsterilized soil was significantly higher than that among the seedlings from untreated seeds. Mortality of P. contorta var. latifolia seedlings was significantly higher among the seedlings from untreated seeds, and that of P. glauca seedlings was higher among the seedlings from untreated seeds and only in unsterilized soil.
METHODS OF PROTEIN EXTRACTION FROM NEUROSPORA CRASSA
Authors: Stine G. J. , Strickland W. N. , Barratt R. W.
Published: February 2010

Nine methods for disrupting the mycelium of Neurospora crassa have been compared. Protein percentages are calculated per gram dry weight of mycelium. A TPN-specific glutamic acid dehydrogenase was extracted and the efficiency of each extraction method is given as total enzyme extracted and specific activity. In terms of total protein, total enzyme, and practicality of the method, the Hughes Press, the French Press and the Raper–Hyatt Press were found to be the most efficient. The advantages and limitations of each method are considered.
PASSIVE NEUTRALIZING ANTIBODIES IN EXPERIMENTAL COXSACKIE B-1 VIRUS INFECTION
Authors: Grodums E. Irene , Dempster George
Published: February 2010

Passive neutralizing antibodies specific to Coxsackie B-1 virus are transmitted from immune mice to the litters both before and after birth.Before birth the antibodies are transmitted via the mother"s blood; their presence could not be detected by the age of 17 days. After birth, the antibodies apparently are transmitted by milk. The ND50of these antibodies is maintained if the litter is suckled by an immune mother.Although the immune 4-day-old litters survive after intracerebral inoculation and there are no signs of paralysis or other severe damage to the CNS, the brain lesions on microscopical examination appear to be as extensive as in the non-immune controls. The brain tissues of the immune mice are spared if the virus is introduced by the subcutaneous route.The damage observed in the interscapular brown fat in either the immune 4- or the 17-day-old mice, irrespective of the route of virus inoculation, is considerably reduced or minimal, if the presence of the passive antibody can be demonstrated in the blood.When the offspring are born of and suckled by an immune mother, the multiplication of the Coxsackie B-1 virus in the brown fat appears to be completely blocked, and there is no evidence of an immediate antigenic stimulus by the challenge virus.
LABORATORY EVALUATION OF SEMISYNTHETIC ANTIBIOTICS AGAINST STAPHYLOCOCCI ISOLATED FROM BOVINE UDDER
Authors: Donaldson J. , Moriarity A. J. , Joshi N. , Dale D. G.
Published: February 2010

A comparison was made of the minimal inhibitory concentrations (MIC) of penicillin G, methicillin, oxacillin, and cephalosporin C for 16 non-penicillinase-producing strains of Staphylococcus aureus from cows with mastitis and on 22 penicillinase-producing strains (20 from cows with mastitis and 2 from humans), All strains were sensitive to methicillin, oxacillin, and cephalosporin C. The addition of whole or skim milk did not affect the tests. Strains with induced resistance to one of the three latter antibiotics developed resistance to the other two. By increasing the inocula of organisms in the test, the MIC was increased to the greatest extent with penicillin, to some extent with oxacillin, and negligibly with the other two antibiotics.
RHIZOSPHERE MICROFLORA ASSOCIATED WITH MYCORRHIZAE OF DOUGLAS FIR
Authors: Neal Jr. J. L. , Bollen W. B. , Zak B.
Published: February 2010

Rhizosphere microflora of three morphologically different mycorrhizae of a Douglas-fir were examined and compared with microflora surrounding adjacent suberized roots and in non-rhizosphere soil. Populations of bacteria, molds, and Streptomyces were different for each microhabitat. Bacteria varied in total numbers and in distribution of morphological and physiological types. A low percentage of Streptomyces and fewer molds were found in mycorrhizal and adjacent suberized root rhizospheres than in the soil mass, Rhizosphere fungi were predominantly members of the genus Penicillium, which also were abundant in non-rhizosphere soil together with representatives of Aspergillus and Trichoderma, Rhizosphere differences between the morphologically distinct white, grey, and yellow mycorrhizae are attributed to the different associated fungal symbionts.
ESTERASE ACTIVITY IN AN ETHYL ACETATE PRODUCING YEAST
Authors: Smith James L. , Martin William R.
Published: February 2010

Whole cells of a yeast formed ethyl acetate from ethanol or glucose under acid conditions only. At pH 5 and above, ethyl acetate formation decreased to a low level probably because of the increased esterase activity of the cells. A cell-free esterase was isolated and partially purified by ammonium sulphate fractionation. The esterase was capable of decomposing both aliphatic and aromatic esters and is probably an aliesterase.
ELECTRON MICROSCOPIC STUDY OF THE FORMATION OF SPINY CONIDIA IN SPECIES OF STREPTOMYCES
Authors: Rancourt Martha W. , Lechevalier H. A.
Published: February 2010

The mode of formation of conidia by a strain of Streptomyces viridochromogenes was followed by the observation of ultrathin sections of aerial hyphae at various stages of sporulation. Before sporulation the aerial hyphae contain a long central strand of nuclear material. The laminated hyphal wall is covered with a fibrous non-spiny layer. At equal intervals, and apparently simultaneously, the hyphal wall becomes involuted while the outer fibrous sheath becomes spiny. The nuclear material constricts, adjacent to the points of involution of the wall. As the involution of the cell wall continues, only a thin isthmus of cytoplasm connects two adjacent future spores. The nuclear material breaks into spheroid structures. The spiny fibrous layer breaks into spore size segments that envelop each spore. An amorphous electron dense material accumulates between adjacent spores during maturation and eventually participates in the formation of interspore pads. Spores in a chain are held together only by the fusion between adjacent interspore pads. As the spores in a chain become fully mature, an area of weakness can be seen between spore pads that are still held together. Although studied in less detail, the mechanism of spore formation is believed to be similar in a strain of S. violaceus.
UREOLYTIC RUMEN BACTERIA: II. EFFECT OF INORGANIC IONS ON UREASE ACTIVITY
Authors: Jones G. A. , MacLeod R. A. , Blackwood A. C.
Published: February 2010

The urease activity of whole cell preparations of the mixed rumen microflora was reduced when the cells were washed with maleate buffer. Resuspension of the washed cells in rumen supernatant liquor (RSL) enhanced their urease activity owing to the presence of an inorganic urease-stimulating factor in RSL. When the whole cells were washed in buffer there was a progressive reduction in the urease activity of the cells as the number of washings increased. This effect was attributed to progressive removal from the cells of the urease-stimulating factor. The urease activity of preparations of whole cells washed three times in buffer was stimulated in the presence of Mn2+, Mg2+, Ca2+, Sr2+, and Ba2+, and inhibited in the presence of Na+, K+, and Co2+. These ions brought about similar effects on the urease activity of acetone-dried powders and cell-free extracts of washed rumen microorganisms. The activity of jack-bean urease was reduced in the presence of the ions which stimulated rumen urease.When inorganic ions were added individually to suspensions of washed rumen microorganisms there were time lags before the ions exerted their stimulating or inhibiting effects on urea hydrolysis. Once the stimulation or inhibition of activity by an ion had begun, however, the reaction proceeded at a constant rate which was characteristic of the ion tested. Modification of the permeability properties of washed cells of rumen microorganisms by acetone treatment modified but did not eliminate the time lags. When a cell-free extract of washed cells was tested, Mn2+, Mg2+, Ca2+, Co2+, and K+all influenced urease activity immediately upon addition to the extract, whereas Sr2+, Ba2+, and Na+were active only after a lag period.The urease produced by rumen bacteria is considered to be a metal-activated, intracellular enzyme. The urease-stimulating factor present in the cells was not bound to any appreciable extent intracellularly. The time lags observed with the whole cells were attributable in most cases to the time taken for the ions to penetrate the cells; with Sr2+, Ba2+, and Na+they were apparently due, at least in part, to a delay in the formation of an active complex between ion and enzyme.
NUTRITIONAL FACTORS RELATING TO GROWTH AND OXYTETRACYCLINE FORMATION BY STREPTOMYCES RIMOSUS
Authors: Zygmunt Walter A.
Published: February 2010

The effects of a variety of nitrogen compounds, mainly amino acids, on oxytetracycline formation and growth were studied in Streptomyces rimosus. Of the amino acids, N-acetyl-DL-alanine and N-acetylglycine supported the highest antibiotic yields. No correlation was evident between the capacity of an amino acid to support growth or stimulate antibiotic formation. Likewise, other adjuncts that stimulated growth did not necessarily enhance antibiotic production. Nutritional differences based on amino acid utilization and antibiotic synthesis using alanine and aspartic acid isomers existed among different strains of S. rimosus. In addition, a synthetic medium was developed that gives excellent antibiotic production though organic nitrogen is omitted.
CELL WALL REPLICATION: II. CELL WALL GROWTH AND CROSS WALL FORMATION OF ESCHERICHIA COLI AND STREPTOCOCCUS FAECALIS
Authors: Chung K. L. , Hawirko R. Z. , Isaac P. K.
Published: February 2010

Cell wall replication in E. coli and S. faecalis was studied by differential labelling of living cells with fluorescent and non-fluorescent antibody.In E. coli the initial step in cell division was the formation of a cross wall at the cell equator, followed by the appearance of new cell wall on either side of the cross wall. The process was repeated in sequence at subsequent sites in the polar, the subcentral, and the subpolar areas. Constriction occurred at random so that the divided parent cells were composed of several daughter cells.A polar type of unidirectional cell wall growth and elongation was also observed in E. coli. It was initiated by the synthesis of a ring of new cell wall material around the polar tip. A second ring was then formed at the subpolar area during the rapid enlargement of the first ring in a single direction.Evidence shows that cell wall synthesis is independent of cell division and that in E. coli, it is initiated at multiple but specific sites within the cell and not by diffuse intercalation of old and new walls.Contrary to the synthesis of cell wall at multiple sites in E. coli, S. faecalis replicated new cell wall at only one site per coccus. The new wall segment was initiated and enlarged at the coccal equator, and was followed by the formation of a cross wall, centripetal growth and constriction to separate the daughter cells.
RESISTANCE OF SALMONELLAE ISOLATED IN 1962 TO TETRACYCLINE, CHLORAMPHENICOL, AND AMPICILLIN
Authors: Yurack J. A.
Published: February 2010

Of 664 Salmonella cultures isolated during 1962 from a variety of sources in Canada, 56 (8.4%) were resistant to one or more of the antibiotics tetracycline, chloramphenicol, and ampicillin. Of the 38 serotypes studied, S. typhimurium and S. heidelberg showed a much higher proportion of strains resistant to tetracycline than did the other serotypes. The incidence of resistant strains among 335 cultures from man was 6.9%; among 74 strains from poultry, 35.1%; while among 52 strains from other animal sources only 5.8% were resistant.
CELLULAR IMMUNITY OF RATS TO TULAREMIA
Authors: Woodward John M. , Stansberry Margaret H. , Presswood William G. , Fox John B.
Published: February 2010

Mononuclear leucocytes harvested from the peritoneal cavities of rats recovered from infection with Pasteurella tularensis, and from those immunized with a killed vaccine, conferred significant resistance against this organism when transferred to normal recipients. It was determined that a minimum of 3.7 × 107leucocytes/rat was required for protection and that only intact cells were effective in providing immunity. The immune response was shown to be specific for tularemia, and was of the passive type, disappearing between 15 and 18 days following cell transfer.
THE DEVELOPMENT OF PENICILLIN-SENSITIVE MUTANTS IN THE COURSE OF NATURAL AND EXPERIMENTAL INFECTION WITH PENICILLINASE-PRODUCING STAPHYLOCOCCUS AUREUS STRAINS
Authors: Borowski Jerzy
Published: February 2010

The frequency of sensitive mutants among Staphylococcus aureus growing under in vitro and in vivo conditions was studied. A total of 3360 colonies recovered from 59 natural human infections was tested for penicillin-sensitivity. To the same examination were submitted 6936 colonies isolated from cultures of 18 S. aureus strains and 34,942 colonies obtained from organs of mice experimentally infected with these staphylococci. We succeeded in demonstrating sensitive colonies among all three groups.
PRODUCTION OF A MELANIN-LIKE PIGMENT AS A RESULT OF CRESOL INHIBITION OF NORMAL PIGMENTATION IN MICROCOCCUS VIOLAGABRIELLAE
Authors: Nichols J. L. , Campbell J. N.
Published: February 2010

When Micrococcus violagabriellae was grown in the presence of 0.01 M cresol, it elaborated a brown pigment which diffused readily into the medium. This pigment was purified and compared with the normal, red, insoluble iron-containing pigment of this organism, as well as the brown pigments, which have been designated as bacterial melanins, isolated from two melanogenic strains of Pseudomonas aeruginosa. The pigment from the inhibited M. violagabriellae resembled those from the P. aeruginosa strains, and melanins of other forms, with regard to absorption spectra, reduction of ammoniacal AgNO3, and susceptibility to bleaching by H2O2. Unlike the Pseudomonas strains, M. violagabriellae required iron for pigmentation, although iron was not incorporated into the pigment, but lacked the ability to produce pigment from either tyrosine or dihydroxyphenylalanine. As a result, the Micrococcus pigment is considered to be an alternate end product of normal pigment synthesis rather than a melanin, and the inhibition by cresol is validated as a tool for the study of normal pigment biosynthesis in M. violagabriellae.
THE DECOMPOSITION OF RADIOACTIVE ACETATE IN SOILS: II. THE DISTRIBUTION OF RADIOACTIVITY IN SOIL ORGANIC FRACTIONS
Authors: Ivarson K. C. , Stevenson I. L.
Published: February 2010

Soils incubated with C14-labelled acetate for 6 to 9 hours showed that 22–30% of the acetate was oxidized to CO2. Fractionation of the soil revealed that the radioactivity of the remaining substrate was widely distributed in various fractions. Greatest activity was noted in the acid hydrolyzable humin fraction (50%) with lesser amounts (5–10%) being recovered in the fulvic acid and alcohol extract. Hymatomelanic acid, α-humus, and β-humus contained only traces of activity.Ion-exchange separation of the acid hydrolysate of the humin fraction indicated that a considerable portion of the activity was associated with an unidentified compound which had certain characteristics of itaconic acid. Radioactivity was also found to be present in the 15 amino acids identified.
BIOSYNTHESIS OF THE PHENYLPROPANOID MOIETY OF CHLORAMPHENICOL
Authors: Vining L. C. , Westlake D. W. S.
Published: February 2010

Cultures of Streptomyces sp. 3022a were grown in the presence of C14-labelled substrates and incorporation of radioactivity into chloramphenicol measured. D-Glucose, labelled in carbons 1 or 2 or uniformly, was an efficient precursor of the p-nitrophenylserinol moiety and of the phenylpropanoid amino acids of the mycelium. The distribution of label in the ring and side-chain carbon atoms of p-nitrophenylserinol and cellular phenylalanine from experiments in which glucose-1-C14, glucose-2-C14, and glycine-2-C14 were fed provided evidence that the two phenylpropanoid systems had a common biosynthetic origin. The results were also consistent with their formation via the shikimic acid – prephenic acid route. Uniformly C14-labelled shikimic acid, though poorly utilized by this organism, was incorporated selectively into both the aromatic portion of chloramphenicol and the aromatic amino acids in the mycelium. L-Phenylalanine-U-C14, L-phenylalanine-carboxyl-C14, L-tyrosine-carboxyl-C14, DL-p-hydroxyphenylserine-2-C14, and acetate-2-C14 were poor precursors of the p-nitrophenylserinol moiety. Since phenylalanine and tyrosine were incorporated into the mycelium the biosynthetic route to the phenylpropanoid portion of chloramphenicol evidently does not pass through either of these amino acids but branches at an earlier step.
SOME CONSIDERATIONS OF THE GROWTH OF MARINE ALGAE IN ARTIFICIAL MEDIA
Authors: McLachlan Jack
Published: February 2010

Growth of 10 species of unicellular marine algae, representative of seven classes, in an enriched seawater medium was compared with growth in several artificial media. All media were buffered with glycylglycine, which was found to be less inhibitory than tris(hydroxymethyl)aminomethane. Growth of most species in natural seawater was superior to that in the artificial media examined, but the addition of 2 mM bicarbonate to these media resulted in improved growth comparable to that in the enriched seawater medium. All organisms were euryhaline and grew well in at least 50% seawater. Although considerable variation in the concentration of the major cations was tolerated, the concentration at which a particular cation limited growth was not the same for each species. Large changes in the magnesium-to-calcium ratio did not appear to affect growth, but a relation between sodium and magnesium and calcium was indicated for several organisms.
NOTES ON THE CYTOLOGY AND SEXUALITY OF PUFFBALLS
Authors: Dowding E. Silver , Bulmer Glenn Stuart
Published: February 2010

In stained squash preparations of young puffballs, the subterminal cells are binucleate. Prophase I of young basidia is too indistinct for details, but metaphase and anaphase I reveal the chromosomes and suggest that their number is n = 3 in Lycoperdon pusillum and Calvatia gigantea, and n = 4 in L. pyriforme and L. curtisii. Each mature basidium contains a tetrad. The basidiospore contains two (sister) nuclei. Hyphae of the species investigated are smooth, lacking clamp connections. Their cells are usually binucleate, but the nuclei are not closely associated in pairs. Such species may be haploid. In a variant of C. gigantea the tissue is made up of much larger hyphae, possessing clamp connections and each cell containing a pair of very large nuclei. The variant is therefore diploid. More of such tissue should be sought.
THE OCCURRENCE OF LAMPROPEDIA IN THE INTESTINES OF SOME REPTILES AND NEMATODES
Authors: Schad G. A. , Knowles Roger , Meerovitch E.
Published: February 2010

Early reports of Lampropedia suggested that it occurred in stagnant or muddy waters, rotting vegetation, and liquid manure. More recently, "window-pane sarcinae" have been observed in the rumen contents of sheep and cattle. Now we have found that this organism is a frequent component not only of the gut flora of herbivorous reptiles but also of nematodes inhabiting the guts of some of these reptiles. This, taken together with the other evidence, suggests that Lampropedia may be often associated with other microorganisms in those parts of the vertebrate alimentary tract in which cellulose digestion is occurring.
THE INCORPORATION OFD-ALLOSE INTO THE GLYCOLYTIC PATHWAY BY AEROBACTER AEROGENES
Authors: Gibbins L. N. , Simpson F. J.
Published: February 2010

A. aerogenes produces an inducible enzyme system that converts allose to fructose-6-phosphate. The first step is a phosphorylation to yield allose-6-phos-phate. Evidence is presented that indicates an isomerase transforms allose-6-phosphate to allulose-6-phosphate which is subsequently converted to fructose-6-phosphate by a 3-epimerase.
PSEUDOURIDINE FROM CULTURE MEDIA OF AGROBACTERIUM TUMEFACIENS
Authors: Suzuki T. , Hochster R. M.
Published: February 2010

Cultures of Agrobacterium tumefaciens grown on a synthetic medium containing glucose plus a pyrimidine produced a pyrimidine riboside with unusual chemical properties. This substance was isolated in crystalline form and identified as 5-ribosyluracil (pseudouridine) on the basis of data obtained from ion exchange and paper chromatography, electrophoresis, ultraviolet and infrared spectrophotometry, color reactions, melting point, elementary analysis, hydrazinolysis, and periodate oxidation followed by bromine treatment.
SEROLOGICAL RELATIONSHIPS OF SOIL ACTINOPHAGES
Authors: Corke C. T. , Robinson J. B. , Douglas R. J.
Published: February 2010

Actinophages first appeared in soil perfusates 4 hours after perfusion began, and, with certain species of Streptomyces, titers as high as 106 plaque-forming units (PFU) per ml of perfusate were reached in from 18 to 24 hours. Samples of soils collected in late summer and fall yielded larger numbers of PFU than did samples collected in the spring. Antisera against two isolated S. scabies phages were used to characterize the "wild" phage populations appearing in soil perfusates. With S. scabies as the plating indicator most phages (92–98%) were found to be related serologically to phage L, and from 2.5% to 7.5% of the total PFU were related to phage S. Further experiments showed that phages related to L appearing in perfused soil were the dominant group acting on S. lavendulae and S. olivaceus.The use of combined antisera for inactivation of perfusate permitted the isolation of new phages normally obscured by the dominant serological groups L and S.
SIZE OF INOCULUM, STIMULATION, AND INHIBITION OF GROWTH IN ASPERGILLUS ORYZAE
Authors: Meyrath J. , McIntosh A. F.
Published: February 2010

Culture filtrates from surface and deep cultures of Aspergillus oryzae were tested for the presence of stimulatory and inhibitory substances, by examining the effect of the nitrates, when added with the inoculum, on growth rate and maximum yield of stationary cultures of the same organism. Filtrates were prepared from various stages of both large- and small-inoculum cultures by each method of growth.Both stimulatory and inhibitory substances were found. Inhibitory substances predominated in the filtrates from early stages of a small-inoculum culture, more especially when these were derived from a deep culture, which showed a pronounced effect of inoculum size. At other stages of growth of small-inoculum cultures and all stages of growth of large-inoculum cultures tested, stimulatory substances were found.It is emphasized that the stage of production of such substances is of crucial importance. Inhibitory substances acting at an early stage of growth of small-inoculum cultures have an adverse effect on growth of late stages. If, however, stimulatory substances are present in sufficiently high concentration at a sufficiently early age, as in large-inoculum cultures, they exert a favorable influence on later stages of growth. These phenomena explain the effects of inoculum size.
BOUND WATER, INOSITOL, AND THE BIOSYNTHESIS OF TEMPERATE AND VIRULENT BACTERIOPHAGES BY AIR-DRIED ESCHERICHIA COLI
Authors: Webb S. J. , Dumasia M. D. , Bhorjee J. Singh
Published: February 2010

The effect of relative humidity (R.H.) and inositol on the capacity of semidried cells of E. coli B to manufacture five bacteriophages, together with the effect of drying on the vegetative phages of infected cells, has been studied. Also, the action of drying and inositol on the induction of lysis and production of lambda phage by E. coli K12 has been examined. It was found that the bound-water content of a cell determined the response of all phenomena to drying. As the R.H. was lowered from 70%, where the bound-water content is approximately 25 g/100 g cell solids, to 40% (10 g/100 g cell solids) a rapid decline in the resistance of both the capacity and vegetative phage occurred. In addition, the extent of vegetative phage inactivation was found to depend on the time after infection and prior to drying. All vegetative phages showed their maximum sensitivity immediately and up to 7 minutes after infection, then their sensitivity decreased and maximal stability occurred 15 minutes after infection. Inositol completely prevented capacity or vegetative phage inactivation under the conditions described. Desiccation was found to induce the lysis of E. coli K12 and the production of lambda phage. In terms of the percentage of viable cells lysed a greater proportion of the cells surviving desiccation at 30% R.H. was found to undergo lysis than those desiccated at 70% R.H., or at all R.H. levels in the presence of inositol.
A CYTOLOGICAL STUDY OF NORMAL AND RADIATION-RESISTANT ESCHERICHIA COLI
Authors: Pontefract R. D. , Thatcher F. S.
Published: February 2010

A series of cultures of Escherichia coli exhibiting resistance to gamma irradiation was studied cytologically. The length of the cells in the cultures increased as the resistance to irradiation increased. The most resistant cultures contained a high percentage of long filamentous cells 30–40 times longer than normal. A striking increase in the apparent number of nuclei per cell accompanied cellular elongation. These resistant cells also exhibited a peculiar "budding" phenomenon which only occurred in the more radiation-resistant cultures. Conjectures are offered on the relationship between these findings and a basis for resistance to irradiation.
SOME NUTRITIONAL STUDIES OF THE GENUS ZYGORHYNCHUS
Authors: Sarbhoy A. K.
Published: February 2010

Nutritional requirements of six species of Zygorhynchus were studied. Two environmental factors, viz. pH and temperature, were studied. Usually a pH near the neutral point was good for growth and sporulation. The author found single maxima for Z. exponens, Z. macrocarpus, and Z. moelleri 2 and double maxima in the rest of the species. The minimum temperature was below 10 °C, the optimum temperature near 25 °C, and the maximum between 30 and 35 °C in most of the species. Pentoses (with the exception of rhamnose) and hexoses were, in general, utilized well. The disaccharides were poor sources with the exception of maltose, which was a good source for all. Raffinose was utilized well except for Z. exponens and Z. heterogamus. Polysaccharides, in general, were found to be good sources. Sugar alcohols were utilized with the exception of dulcitol. Organic acids did not support growth in all the species.Nitrates were utilized by Z. exponens, Z. moelleri 2, and Z. heterogamus but not by the others. Ammonium nitrogen was more readily utilized than nitrate or nitrite nitrogen. Amino acids, in general, were readily utilized. Glutamic acid was better than aspartic acid.Sulfate, sulfite, bisulfite, and metabisulfite were utilized well. Among the organic sources of sulfur, thiourea, cystine, and methionine were moderately good for almost all the species.There was no correlation between growth and sporulation. Almost every grade of sporulation was noticed with significantly good or poor growth. All the sources of carbon, nitrogen, and sulfur tried, which supported vegetative growth, also induced zygospore formation in the various species, but not in Z. macrocarpus.
BEER-SPOILAGE BACTERIA AND THEIR CONTROL WITH A PHOSPHORIC ACID – AMMONIUM PERSULFATE WASH
Authors: Bah Stanley , McKeen W. E.
Published: February 2010

Flavobacterium proteus, Acetobacter aceti, Acetobacter capsulatum, Pediococcus cerevisiae, and Lactobacillus pastorianus were isolated from contaminated yeast in certain Canadian breweries. F. proteus was most prevalent in ale yeast, while L. pastorianus and P. cerevisiae were most prevalent in lager yeast but the plant also affected the prevalence of the species.A phosphoric acid – ammonium persulfate wash was developed which has proved very effective in the breweries in which it has been used since 1960. Treatment time is very short (2 hours) and consequently a great saving in plant equipment and labor has resulted.The fermentative ability and viability of Saccharomyces cerevisiae is not affected nor is it killed even when it is treated with a phosphoric acid – ammonium persulfate wash that is six times as strong as the one recommended for use in the brewery.
A ROUTINE DETERMINATION OF THE OPTICALLY ACTIVE ISOMERS OF LACTIC ACID FOR BACTERIAL CLASSIFICATION
Authors: Cato Elizabeth P. , Moore W. E. C.
Published: February 2010

The quantity of L(+)-isomer of lactic acid is determined with L(+)-specific lactic dehydrogenase. Comparison with the total amount of lactic acid determined chromatographically is used as a rapid and accurate replacement for the classical determination of optically active isomers of lactic acid for classification of lactic acid bacteria.