摘要:

The nutritional requirements of 14 cultures ofBacillus coagulans, which were isolated and identified in this laboratory, and eight other authentic strains of this organism, were studied at 37 °C. Biotin and thiamine were required by all strains in a semisynthetic medium containing enzymatic casein hydrolyzate, glucose, and mineral salts. In addition, one strain required niacin. An additional requirement for folic acid (or PABA) was noted for most strains in a synthetic medium. With few exceptions, the amino acid requirements were non-specific. Glutamic acid appeared essential for a few strains and stimulated others.

ISSN:0008-4166    

DOI:10.1139/m57-057

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Cultures of over 600 fungi were screened for the production of extracellular free lysine in submerged agitated culture on a medium containing urea, cerelose, and mineral salts. Sixty-three of the isolates produced free lysine in quantities sufficient to be detected by a turbidimetric bio-assay procedure, and 12 of these produced 5-15 γ lysine per milliliter of culture nitrate. With two strains ofUstilago, yields were increased to 200–300 γ lysine per milliliter culture mixture by adjustment of cultural conditions. The addition of ammonium acetate or of acetic acid, or the increasing of the amount of urea in the medium from 0.06% to 0.6%, resulted in increased yields from certain organisms.

ISSN:0008-4166    

DOI:10.1139/m57-058

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Strains ofBacillus cereuspathogenic for the larch sawfly,Pristiphora erichsonii, produce an enzyme that breaks down purified egg lecithin and the phospholipids of egg yolk and insect tissue. A study, using specific chemical techniques to measure lecithinase activity, of the relation between lecithinase production and pathogenicity supports an earlier postulate that lecithinase plays a role in the pathogenicity ofB.cereusfor the larch sawfly.

ISSN:0008-4166    

DOI:10.1139/m57-059

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Proteinase biosynthesis byStreptococcus liquefaciens, strain 31, may be obtained from an entirely synthetic medium. Adenine and uracil seem to satisfy best the purine and pyrimidine requirement while pyridoxal and riboflavin is the combination of vitamins that leads to maximal enzyme biosynthesis. Biotin and folic acid together, or thiamine, have an inhibitory effect on enzyme synthesis. The amino acid requirements for optimum activity are unaffected by the reduced number of vitamins and nitrogen bases present in the final medium as compared to the initial medium. A reduction in the number of vitamins (to pyridoxal and riboflavin), however, showed that only adenine and uracil gave the best response to the purine and pyrimidine demands for biosynthesis; prior to this, in the presence of a complete vitamin pool, several combinations of nitrogen bases yielded equal enzymatic activity. When proteinase synthesis is plotted against time, enzyme formation ceases at about 3 hours. The shape of the curve indicates a straight-line relationship after an initial lag period of 90 minutes.

ISSN:0008-4166    

DOI:10.1139/m57-060

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

A study was made of the effects of oxygen tension and inorganic phosphate concentration on the production of glycerol, arabitol, and ethanol by a strain of osmophilic yeast. Increasing the oxygen tension increased the yields of glycerol and arabitol and decreased the yield of ethanol, while increasing the concentration of inorganic phosphate had the opposite effect.The changes in yields of products with increasing phosphate concentration were most pronounced at a partial pressure of oxygen of 280 mm. of mercury. At lower oxygen tensions the yields of polyols were low and the yield of ethanol was high at all concentrations of phosphate, while at very high oxygen tensions the opposite effect was observed. When the ethanol yield was high, the respiratory quotient was also high. These results are discussed in relation to the oxidative phosphate-lack theory of the Pasteur effect.

ISSN:0008-4166    

DOI:10.1139/m57-061

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Although folic acid antagonists have been reported to be unable to inhibit nonfolic-acid-requiring organisms, it was found that several such antagonists were quite active inhibitors ofLactobacillus arabinosusand several species of yeasts when grown in minimal media. The growth inhibition produced under these circumstances was not reversed by compounds related to folic acid but was reversed by thiamine and vitamin B6compounds. A rapidly developing physiological adaptation caused by the presence of thiamine and vitamin B6apparently was the mechanism by which these organisms overcame the inhibitory effects of folic acid antagonists. 6-Mercaptopurine antagonized this reversal and thus was strongly synergistic with folic acid analogues under certain conditions.

ISSN:0008-4166    

DOI:10.1139/m57-062

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

A new species ofHaemophilus,Haemophilus vaginalis, has recently been incriminated as the cause of human non-specific vaginitis and urethritis. A very similar if not identical organism obtained from the same sources is the subject of this report. The nameH.vaginalisis accepted for it. A systematic description of this organism is given, including microscopic and colonial appearances, nutritional requirements, biochemical properties, and pathogenicity to experimental animals. Immunological studies are not yet complete. Transformation ofH.vaginalisinto the L form of colony is described and illustrated in a series of photomicrographs. It is suggested that the pleuropneumonia-like organisms frequently encountered in genitourinary infections are, in fact, L forms ofH.vaginalis. Attention must in future be concentrated on the normal bacterial phase and not on the L phase which is probably not pathogenic.

ISSN:0008-4166    

DOI:10.1139/m57-063

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Using heated antigens, antisera were prepared against the somatic antigens of 16 strains ofSerratia marcescens. By means of cross-agglutination tests it was possible to divide the strains into six groups. Groups II and VI each contained mutually adsorptive strains, which indicated that the members within respective groups are closely related. No correlation was observed of serological activity and pigment production among the pigmented and non-pigmented strains.

ISSN:0008-4166    

DOI:10.1139/m57-064

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Saccharomyces fragiliswas grown at oxygen absorption rates of 0.4, 1, 3, and 5.2 g. per liter per hour both at 20 °C. and at 37 °C. A high rate of yeast production as well as alcohol formation was found at 37° and all four oxygen absorption rates. At 20° alcohol was formed only at the two lowest rates of oxygen absorption. An exponential relation between the maximum yeast population density possible without alcohol production and the rate of oxygen absorption was derived.

ISSN:0008-4166    

DOI:10.1139/m57-065

出版商:NRC Research Press    

年代:1957

数据来源: NRC

摘要:

Dematium nigrum, a common laboratory contaminant, was found to have an unsuspected ability to cause a neurological syndrome in mice. Intravenous injection of a suspension caused a fatal, right-sided hemiparesis. Death occurred, most often, after 6–10 days. The organism could be recovered from the brains of afflicted animals but not from other organs.

ISSN:0008-4166    

DOI:10.1139/m57-066

出版商:NRC Research Press    

年代:1957

数据来源: NRC