摘要:

Oxygen was found to have no effect on the induction of the λ prophage due to desiccation but enhanced cell death and the inactivation of the intracellular phages at relative humidity (R.H.) levels below 40%. The magnitude of the oxygen effect increased as the R.H. below 30% decreased. Inositol prevented cell death and phage inactivation due to both bound water reorientation and oxidations. Cells freeze-dried before aerosolization were more stable to storage in air at 30% R.H. and below than they were at 40% to 70% R.H. However, most of the killing of pre-dried cells held at 20% R.H. and below in air was found to be due to an effect of oxygen.

ISSN:0008-4166    

DOI:10.1139/m67-097

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Success in immunizing animals with dead trypanosomes depends on both the method of inactivating trypanosomes and the strain used for immunization. Comparative studies with various inactivating agents showed that β-propio-lactone and formalin are superior to phenol, heat at 56 °C, and lysis in distilled water. A vaccine containingTrypanosoma bruceiwith frequent passages through mice and not exposed to antibodies could elicit in animals protective antibodies and resistance to a challenge with a homologous strain. Passive immunity was shown in young mice born of vaccinated mothers. On the other hand, no active or passive immunity was demonstrated when animals were immunized with a vaccine prepared from a variant ofT.bruceiafter passage through rabbits or sheep.

ISSN:0008-4166    

DOI:10.1139/m67-098

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Phosphate solubilizing ability of different isolates of fungi associated with legume root nodules was studied in vitro. Among the fungi tested, isolates ofPenicillium lilacinum,Aspergillussp.,A.flavus,A.niger,A.terreus, andA.nidulanssolubilized insoluble tricalcium phosphate. When soluble potassium dihydrogen phosphate was present with tricalcium phosphate in the medium, some of the fungi failed to solubilize phosphate.

ISSN:0008-4166    

DOI:10.1139/m67-099

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

The fatty acid compositions of 17Entomophthoraisolates, together with those of 8 other fungi, were determined. γ-Linolenic acid was present in all fungi examined, and eicosatrienoic and arachidonic acids were found in all but the threeBasidiobolusspecies andRhizopus nigricans. All but two of theEntomophthoraisolates could be divided into three groups on the basis of their fatty acid composition. Of the other fungi examined, only the fatty acid compositions of theConidiobolusspecies show close correlation with those ofEntomophthoraspecies.

ISSN:0008-4166    

DOI:10.1139/m67-100

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

A strain ofPseudomonaspreviously used to study the oxidative degradation of phenylacetic acid and phenylpropionic acid has been used to study the degradation ofp-hydroxybenzoic acid,L-tyrosine,L-phenylalanine, phenylbutyric acid, and phenylvaleric acid.p-Hydroxybenzoic acid was converted to 3, 4-dihydroxy-benzoic acid and the aromatic ring was cleaved between carbons 3 and 4. Previous results showed that cleavage of 3, 4-dihydroxyphenylacetic acid occurred between carbons 2 and 3. Phenylalanine and tyrosine were metabolized by the homogentisic acid pathway. These results, together with results of previous work, suggest that the pathway used for the degradation of aromatic compounds by this organism varies with the nature of the side chain. The metabolism of aromatic compounds with side chains longer than three carbons appears to involve oxidative shortening of the side chain prior to cleavage of the aromatic ring.

ISSN:0008-4166    

DOI:10.1139/m67-101

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Incidences of soil fungi were recorded for 1 cm3volumes of untreated and fumigated nursery soils using new selective isolation media. In July, 10 months after application of Trizone at 1 lb/100 ft2, there were many viablePythiumpropagules in the treated surface soil (11/cm3) but significantly fewer than in nonfumigated soil (29/cm3). Studies with baits showed thatRhizoctoniaandFusariumspp. were also present in both soils. The total number of fungi in fumigated soil (11,000) was lower than in nonfumigated soil (30,000).Trichodermapropagules were very common and significantly more so in fumigated (1,120) than in nonfumigated (270) soil. The same held for bacteria (10 million vs. 7 million). Reinfestation with four potentially pathogenic genera of fungi was found to take place by means of splashing rain and irrigation water, dust, and soil carried by man.

ISSN:0008-4166    

DOI:10.1139/m67-102

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Ninety-one strains of yeast from 19 genera were examined for their ability to utilize singleL- andD-amino acids as the nitrogen source for growth. Eighty strains from 17 genera were able to grow on at least oneD-amino acid. The most readily utilized were alanine, α-amino butyric acid, leucine, and serine.D-Cysteine was used by few species. The utilization ofD-amino acids is of little use in classifying or identifying yeasts.

ISSN:0008-4166    

DOI:10.1139/m67-103

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Eleven imidazoles were tested singly as nitrogen sources for 62 strains of yeast.L-Histidine and histamine were used by most strains,D-histidine by some, and histidinol only by a few. Four yeasts grew on compounds containing nitrogen only in the imidazole ring.Lipomyces starkeyiiandLipomyces lipoferusgrew on imidazole, imidazole-4-methanol, imidazole-4-carboxylic acid, imidazoles-4-propionic acid, and urocanic acid. The twoLipomycesspecies,Trigonopsis variabilisandTorulopsis gropengiesseri, were able to grow on imidazole-4-acetic acid and imidazole-4-lactic acid.

ISSN:0008-4166    

DOI:10.1139/m67-104

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Studies of differences in hydrolase activity of peritoneal mononuclear leucocytes from normal rats and rats given three injections of killedFrancisella tularensisvaccine demonstrated increases of 37–69% in ribonuclease, deoxyribonuclease, and acid phosphatase in lysates of cells obtained from vaccinated animals. No deviation from normal was observed for B-glucuronidase, alkaline phosphatase, or cathepsin. Following a single injection of vaccine the activity of ribonuclease, deoxyribonuclease, and acid phosphatase decreased slightly and then increased, reaching a maximum of 96 h and returning to normal levels after 30 d. Stimulation of the animals with a second injection of vaccine at 96 h resulted in an immediate and pronounced depression in activity of deoxyribonuclease and acid phosphatase which also was followed by an increase similar to that observed initially. Analysis of the various leucocytic fractions revealed 52.2–56.4% of the total enzymatic activity to be associated with the cytoplasmic granules.

ISSN:0008-4166    

DOI:10.1139/m67-105

出版商:NRC Research Press    

年代:1967

数据来源: NRC

摘要:

Cultures ofNeurospora crassathat are shaken are capable of producing conidia on anmedium which does not support conidial formation under standing conditions. A decrease in oxygen tension from 160 mm Hg causes a regular decrease in growth rate, a promotion in alcohol production, and a delay in conidia formation. In a medium withas the nitrogen source, oxygen tensions from 160 to 60 mm Hg do not greatly alter the growth rates, alcohol production is increased, and conidiation is delayed. Oxygen tensions below 60 mm Hg further delay conidiation, sharply decrease dry weight, and accelerate the production of alcohol 20 to 30% over amounts produced in themedium.

ISSN:0008-4166    

DOI:10.1139/m67-106

出版商:NRC Research Press    

年代:1967

数据来源: NRC