摘要:

A group of 53 normal human plasma samples showed variable staphylococcal anti-delta-hemolysin activity. Albumin and globulin in low concentrations did not interfere with the hemolytic activity of delta lysin. Rabbit and guinea pig sera contained anti-delta lysin in low titer.Staphylococcus aureus209 produced equal zones of hemolysis when grown on washed erythrocyte agar plates prepared from 16 different human blood samples while whole blood agar plates prepared from the same blood gave variable and smaller zones under similar conditions.

ISSN:0008-4166    

DOI:10.1139/m67-124

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The sensitivity to interferon, and interferon-producing capacities of three plaque variants of Mengo virus have been studied. It has been shown that the Mengo variants, which differ greatly in their pathogenicity for mice, induce the production of very little interferon in L cells or primary mouse embryo fibroblasts, and that all are about half as sensitive to inhibition by interferon as is vesicular stomatitis virus. Serum and brain interferon titers closely parallel serum and brain virus titers following the intraperitoneal injection of mice with 106plaque-forming units (PFU) of each variant, but there is little difference in the amounts of interferon produced in lethal and in non-lethal infections. It is concluded that interferon production in vivo is unlikely to be more than a minor defense mechanism against infection with Mengo virus.

ISSN:0008-4166    

DOI:10.1139/m67-125

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Three isolates ofSclerotinia trifoliorumErikss. grew well in stationary culture in a synthetic liquid medium containingDL-asparagine, mineral salts, and a number of carbon sources representing monosaccharides, oligosaccharides, polysaccharides, and carbohydrate derivatives.D-Glucose,D-galactose,D-mannose, sucrose, lactose, dextrin, starch, and glycogen were the best carbon sources.D-Fructose, maltose, cellobiose, raffinose, and inulin supported considerable growth but somewhat less than the previous group. All other sources were utilized only slightly for growth during a 3-week incubation period. Significant differences among the isolates were observed on a number of carbon sources.L-Sorbose was utilized only slightly for growth during an 8-week incubation. WhenL-sorbose contributed one-half of the carbon in mixed media, growth was inhibited for 4 weeks in the presence ofD-glucose and for the duration of the test period (8 weeks) in the presence of sucrose and maltose. Other monosaccharides, not utilized for growth when present alone in the medium, did not inhibit growth when in the presence ofD-glucose. When the proportion of carbon contributed byL-sorbose was reduced to one-third, inhibition of growth was decreased.

ISSN:0008-4166    

DOI:10.1139/m67-126

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

It was found that 4.9% of 1065 coagulase-positive and 8.5% of 387 coagulase-negative strains ofStaphylococcusproduced antibiotics inhibiting growth of the indicator strain,Staphylococcus aureusOxford 209P.Zones of inhibition on solid media ranged from slight to 6 mm. Antibiotics produced by several of the most active strains were investigated in detail. With one or two exceptions, these substances inhibited the growth of Gram-positive rather than Gram-negative bacteria. Most staphylococcal strains were found to be more sensitive to antibiotics produced by coagulase-negative than positive strains selected. At the concentration used, these antibiotics did not kill all cells of the indicator strain,S.aureus209P.The activity of the antibiotics was not totally destroyed by autoclaving or proteolytic enzymes, and was unaffected over the pH range 2.0–11.0. The antibiotics were dialyzable and their activity was inhibited by 10−3 Mconcentrations of EDTA but not by citrate.

ISSN:0008-4166    

DOI:10.1139/m67-127

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Various physicochemical characteristics and the biological activity of two murine lymphoma viruses (S-63 and GC), originally isolated in this laboratory and previously reported as sharing common antigenic properties with human and bovine lymphomas, are defined. These viruses are stable at temperature ranges from −70 °C to +4 °C and are inactivated after incubation at +56 °C for 30 min. They withstand lyophilization and are inactivated by treatment with ethanol, acetone, ethyl ether, formalin, and phenol. Both agents are of the ribonucleic acid, double-membraned viruses, similar to myxoviruses, and are approximately 100 mμ in size.

ISSN:0008-4166    

DOI:10.1139/m67-128

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Papain digest of beef broth (P.D.B. broth) was used to growCorynebacterium diphtheriaein submerged culture, and high potency diphtheria toxins were produced. It was found that the resultant toxoids could sensitize animals to beef proteins. Guinea pigs immunized with deep culture toxoid in complete Freund's adjuvant exhibited anaphylaxis when challenged with beef serum. When aluminium phosphate andBordetella pertussiswere used as adjuvant or when the toxoid was given alone (i.e. without adjuvant) the responses to beef serum were reduced but the sensitivity to beef was still observed. Deep culture toxoids from three other manufacturers were tested and showed similar properties. When concentrated P.D.B. broth was used as a challenge dose, anaphylactic reactions were also noted, indicating that P.D.B. broth, as usually prepared, contained bovine antigens.

ISSN:0008-4166    

DOI:10.1139/m67-129

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Culture filtrates ofSchizophyllum communehave been subjected to ion-exchange chromatography, and the laminarin-splitting and endo-β-glucanase activities have been studied with respect to pH behavior, heat inactivation kinetics, effects of inhibitors, and hydrolysis products. Evidence is presented to show that the two activities may be due to the same enzyme and that a β-(1 → 3) linkage may be involved in the specificity of the enzyme.

ISSN:0008-4166    

DOI:10.1139/m67-130

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

A relatively rapid and sensitive method for the bioassay of seawater for dissolved biotin is described. The uptake of14CO2by cells ofAmphidinium carteriin 2 h following a 94-h preincubation under carefully controlled conditions is proportional to biotin concentrations in seawater. Cell numbers can also be used to measure response to vitamin concentrations but the incubation time is extended to 144 or 168 h. The range of biotin concentrations capable of being assayed is 0.2–6.0 ng/l. These amounts are considerably less than those previously described.

ISSN:0008-4166    

DOI:10.1139/m67-131

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

A study was made on the toxicity of polymyxin B to two blue-green algae. Above a critical cell density, the toxicity level of polymyxin related to cell density ofAnacystis nidulansandChlorogloea fritschiiwas approximately linear. Below this the toxicity level was almost independent of cell density. Polymyxin was much more toxic toA.nidulansin the light than in the dark. Contrary to what might be expected from the known properties of polymyxin, no interference with polymyxin toxicity by any cation could be detected.

ISSN:0008-4166    

DOI:10.1139/m67-132

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

It has been shown that a strain ofChlamydomonas reinhardtiproduces the following α-keto acids: α-ketosuccinic, α-ketoglutaric, pyruvic, α-ketobutyric, and α-ketoisovaleric. The α-keto acids obtained from cells and culture filtrates were identified as their 2,4-diaitrophenylhydrazones by thin-layer chromatography. Identification was confirmed by reduction of the keto acid hydrazones to amino acids, which were analyzed by thin-layer chromatography.

ISSN:0008-4166    

DOI:10.1139/m67-133

出版商:NRC Research Press    

年代:1967

数据来源: NRC