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1.
Previous studies performed on guinea pigs demonstrated a direct dependence of tuberculin reaction size (in vivo hypersensitivity) on immunogenicity in a number of BCG strains. The present work used an in vitro method, MIF detection, for assessing hypersensitivity and compared the results obtained with tuberculin hypersensitivity tests, correlating the data with the immunogenicity of the individual BCG strains employed. The following strains were used: the Czechoslovak BCG strain No. 725, Japanese BCG strain Tokyo, Danish BCG strain Copenhagen and Soviet BCG strain Moscow. The results obtained by the two hypersensitivity testing methods, in vivo and in vitro were in a direct correlation; a direct relationship was also demonstrated between hypersensitivity tested by the in vitro method and immunogenicity. The in vitro method of MIF detection is reproducible and comparable with the other two methods employed and may be used as an alternative approach to BCG vaccine efficacy testing. It might probably also be applicable to estimation of the status of cell-mediated immunity against intracellularly parasitizing bacteria in general.  相似文献   

2.
The California (LGCA) and Butte Sink (LGBS) strains of the sterol auxotrophic fungus Lagenidium giganteum (Oomycetes: Lagenidiales) enter the sexual cycle on media supplemented with sterols. A third isolate of this mosquito pathogen, the North Carolina strain (LGNC), requires sterols plus phospholipids to produce oospores in vitro. Enrichment of the polar and neutral lipid fractions of the LGCA and LGBS strains with unsaturated fatty acids promoted oospore induction, and increased oospore viability. With the exception of the LGCA strain, there was no consistent relationship between phospholipid supplementation in growth media and mycelial phospholipid content.  相似文献   

3.
Lipids were extracted from the cells of Acinetobacter calcoaceticus EB 10 C IMET B 395 grown on gas oil (Bp. 240–360 °C) with benzine/alcohol (80 : 20). The lipid-hydrocarbon-extract obtained by this extraction method was 18.4%. The extract was composed of hydrocarbons, waxes, phospholipids, fatty acids, glycerides, and ubiquinones. The main components among the lipids were waxes. The compositions of phospholipid, fatty acid, wax, and ubiquinone fractions were analysed.  相似文献   

4.
The fractional composition of lipids was studied in 32 yeast strains belonging to the genera of Rhodotorula Harrison, Lipomyces Lodder et Kreger van Rij and Cryptococcus Kutz. The effect of C/N ratio in the growth medium on the content of various lipid fractions was studied. Lipids of the most studied cultures were found to contain di- and triglycerides, waxes, free fatty acids, sterines, their esters, and phospholipids. The fraction of monoglycerides was also detected in Rhodotorula and three species of Cryptococcus, but not in Lipomyces and Cr. laurentii. If C/N ratio equals 10, the predominant lipid component in Lipomyces is triglycerides, and in Rhodoturula and Cryptococcus phospholipids. The fraction of triglycerides prevailed in all cultures at C/N ratio of 100. The content of phospholipids decreased with an increase of C/N ratio in the medium from 10 to 100.  相似文献   

5.
Phospholipase A2 present in a highly purified, potently bactericidal, fraction from rabbit graulocytes produces net bacterial phospholipid degradation during killing of a phospholipase A-less strain of Escherichia coli. In the wild-type parent strain phospholipid breakdown is caused not only by the action of phospholipase A2 but also by phospholipase A1, indicating activation of the most prominent phospholipase of E. coli. This activation occurs as soon as the bacteria are exposed to the granulocyte fraction. Phospholipid breakdown by both phospholipases A is dose dependent but reaches a plateau after 30-60 min and at higher concentrations of the fraction. Phospholipid degradation is accompanied in both strains by an increase in permeability to actinomycin D that is also dose dependent. Even though net hydrolysis of phospholipids is greater in the parent strain than in the mutant, the increase in permeability is the same in the two strains. The addition of 0.04 M Mg2+, after the effects on phospholipids and permeability have become manifest, initiates in both strains the restoration of insensitivity to actinomycin D, the net resynthesis of phospholipids, and the disappearance of monoacylphosphatides and the partial disappearance of free fatty acids that had accumulated. Loss of ability to multiply is not reversed by Mg2+ in either strain. Less than 5 micrograms of granulocyte fraction causes loss of viability of from 90 to 99% of 1 X 10(8) microorganisms of both strains. However, at lower concentrations the parent strain is considerably more sensitive to the bactericidal effect of the granulocyte fraction than the mutant strain.  相似文献   

6.
Phospholipase A2 present in a highly purified, potently bactericidal, fraction from rabbit granulocytes produces net bacterial phospholipid degradation during killing of a phospholipase A-less strain of Escherichia coli. In the wild-type parent strain phospholipid breakdown is caused not only by the action of phospholipase A2 but also by phospholipase A1, indicating activation of the most prominent phospholipase of E. coli. This activation occurs as soon as the bacteria are exposed to the granulocyte fraction. Phospholipid breakdown by both phospholipases A is dose dependent but reaches a plateau after 30–60 min and at higher concentrations of the fraction.Phospholipid degradation is accompanied in both strains by an increase in permeability to actinomycin D that is also dose dependent. Even though net hydrolysis of phospholipids is greater in the parent strain than in the mutant, the increase in permeability is the same in the two strains.The addition of 0.04 M Mg2+, after the effects on phospholipids and permeability have become manifest, initiates in both strains the restoration of insensitivity to actinomycin D, the net resynthesis of phospholipids, and the disappearance of monoacylphosphatides and the partial disappearance of free fatty acids that had accumulated. Loss of ability to multiply is not reversed by Mg2+ in either strain. Less than 5 μg of granulocyte fraction causes loss of viability of from 90 to 99% of 1 × 108 microorganisms of both strains. However, at lower concentrations the parent strain is considerably more sensitive to the bactericidal effect of the granulocyte fraction than the mutant strain.  相似文献   

7.
Total cellular lipids of the synthetic of vitamin B12 Act. olivaceus involve predominantly phospholipids (about 70%). Lipid phosphates consist of phosphatidyl ethanol amine and phosphatidyl-2,3-butandiol (over 40 and 30%, respectively) and lower quantities of phosphatidyl inositol olmonomanoside and cardiolipin. The neutral fraction includes the predominating fraction of triglycerides (over 20%) as well as mono- and diglycerides, free fatty acids, hydrocarbons and three fractions similar to waxes, sterines and sterine esters in their Rf values.  相似文献   

8.
For 31 clinical strains of S. aureus the correlation between phenotype and genotype of resistance to macrolides, lincosamides and streptogramins B (MLSB) was established.. Phenotypes were determined on the basis of: susceptibility to erythromycin and clindamycin and the ability to an induction of the resistance (phenotypes S, susceptible; R , constitutive resistant, D, resistant after induction with erythromycin, D+, resistant after induction with erythromycin and with a presence of the small colonies inside inhibition zone between erythromycin and clindamycin discs), and on the basis of the resistance to spectinomycin (spR, resistant, spS, susceptible). Among examined S. aureus strains eight phenotypes of resistance to MLSB were recognized (the corresponding genotypes are given in brackets). Six phenotypes were typical: SspS (lack of MLS-B resistance genes), NEGspS (msrA/B, 1 strain), D+spS (ermCi, 4 strains),. DspR (ermAi, 11 strains and ermAi + msrA/B, 2 strains), RspR (ermAc, 4 strains and ermA + msrA/B,1 strain and ermA + ermC, 1 strain) and RspS (ermCc, 6 strains and ermB, 1 strain). Two rare phenotypes in two single strains were observed: SspR (ermAi, the strain with altered inducibility, inductor other than erythromycin) and DspS (ermAi, presumably mutation or lack of spc in Tn554).  相似文献   

9.
10.
Hypersensitivity to the toxic effect of benzo(a)pyrene (B(a)P) was determined in homozygous larvae of two D. melanogaster mus strains (mus 208B2 and mus210). The two others (mus205B1 and mus208B1) were found to be less sensitive and the parent strain was resistant. The lack of correlation between the sensitivity in larvae and the activity of aryl hydrocarbon hydroxylase in S15 fractions from adult flies whole body homogenates of the same strains was demonstrated. The hypertoxic effect of B(a)P and 2-acethylaminofluorene in strain mus210 seems to be rather specific because noncarcinogenic pyrene, benzo(e)pyrene and fluorene did not affect the survival of this most sensitive strain. Perspectives of the strain mus210 use for the environmental genotoxic pollutants screening were discussed.  相似文献   

11.
Agglutination and fluorescent-antibody methods were employed for screening Clostridium perfringens types C and D from 393 isolates of this organism. All of 50 strains which were isolated in Japan and were agglutinable with an antiserum prepared against a stock strain of type C no. 3182 toxigenically belonged to type C, but the antiserum showed no cross-agglutination with any of type C strains isolated in Denmark. All of the latter strains, however, were agglutinated by an antiserum prepared against a Danish strain, CWC11. Of 64 strains, showing heat-labile agglutinability by type D antiserum L9, 22 strains were toxigenically identified as type D strains which can be divided into three groups by the heat-stable antigens; no strains which were L-agglutination-positive but O-agglutination-negative were epislon-toxigenic. All of 13 strains, the heat-stable antigen of which was agglutinable by a type D antiserum VX81, were toxigenically type D strains. The results of fluorescent-antibody tests were almost in agreement with those of agglutination test with type C strains and completely with those of the O-agglutination test with type D strains. No beta-, epsilon- or delta-toxigenicity could be demonstrated in strains which were not agglutinated by our test sera for types C and D strains. Further examination of cultural properties of Japanese and Danish type C strains revealed that the two groups were considerably different in urease production, capsule formation, and delta- and alpha-toxigenicities.  相似文献   

12.
The distribution of cucurbitacins in seeds and growing plants of Iberis umbellata L. has been investigated. The testas of 'Giant Pink', 'Purple', 'Crimson' and 'Iceberg' (Dutch) strains of Iberis umbellata contain Cucurbitacin B with traces of D and E. Seeds of 'Iceberg' (Danish) strain were exceptional in containing cucurbitacins E and I but no B, and this strain was also distinguished by larger redder seeds and by testas which were not readily separable into two layers. Cucurbitacins are rare in other crucifers but they are present in I. gibraltarica L., I. sempervirens L. and Lepidium sativum L.  相似文献   

13.
Euchromatic and heterochromatic fractions obtained by autodigestion of mouse TLT (taper liver tumour) hepatoma chromatin (Paul, I. J & Duerksen, J. D. (1976) Arch. Biochem. Biophys. 174, 491-505) were analyzed for relative protein content and histone content. With one exception, all fractions had the same DNA to protein ratio. Similarly, the total histone to DNA ratio was also constant in all fractions. In addition, the relative contents of the major histones, H1, (H2A + H2B + H3), and H4, were also constant in all fractions.  相似文献   

14.
Experiments were carried out to examine the growth and metabolism of thermotolerant yeast Candida tropicalis K-41 and bacteria Micrococcus freudenreichii that do not have a single temperature point but instead have an optimal temperature plateau at which the growth rate and biosynthetic activity remain unaltered or change insignificantly. Upon transition from the carbohydrate to the hydrocarbon pattern of nutrition these microorganisms show significant changes in metabolic processes: optimal concentration of biotin in the medium decreases significantly; the synthesis of riboflavin, nicotinic and pantothenic acids increases in yeast; the synthesis of nicotinic acid, biotin and vitamin B12 increases in bacteria. During microbial cultivation on hydrocarbons the content of cell lipids grows; yeast accumulate actively phospholipids and free fatty acids; bacteria build up intensively waxes and phospholipids. With the near-maximal growth rate the total synthesis of lipids decreases on carbohydrates and increases drastically on hydrocarbons, primarily at the expense of the above fractions.  相似文献   

15.
Studies on the rate and extent of galacturonic acid and isolated pectin digestion were carried out with nine strains of rumen bacteria (Butyrivibrio fibrisolvens H10b and D16f, Bacteroides ruminicola 23 and D31d, Lachnospira multiparus D15d, Peptostreptococcus sp. D43e, B. succinogenes A3c, Ruminococcus flavefaciens B34b, and R. albus 7). Only three strains, 23, D16f, and D31d, utilized galacturonic acid as a sole energy source, whereas all strains except A3c and H10b degraded (solubilized) and utilized purified pectin. Nutrient composition of the basal medium and separate sterilization of the substrate affected the rate and extent of fermentation for both substrates. Pectin degradation and utilization were measured with two maturity stages each of intact bromegrass and alfalfa. For bromegrass I, all strains tested (B34b, 23, D16f, D31d, D15d, and D43e) degraded a considerable amount of pectin and, with the exception of B34b, utilized most of what was degraded. Similar, but lower, results were obtained with bromegrass II, except for the two strains of B. ruminicola, 23 and D31d, which were unable to degrade and utilize pectin from this forage. All strains were able to degrade and utilize pectin from both maturity stages of alfalfa; however, values were considerably lower for strains 23 and D31d. Synergism studies, in which a limited utilizing strain, B34b, was combined with the limited degrading strain, D31d, resulted in a slight increase in degradation and a very marked increase in utilization of the pectin in all four forages. Similar results were obtained on both alfalfa substrates with a combination of strains B34b and D16f; however, no increases were observed with this combination on bromegrass.  相似文献   

16.
The presence of phospho-beta-glucosidases and beta-glucoside permeases was found in strains of Streptococcus, Bacillus, and Staphylococcus. In streptococci, the phospho-beta-glucosidase activity depends on the antigenic group. The highest activity was found in strains of group D. In group D strains, phospho-beta-glucosidase activity is induced by beta-methyl glucoside and cellobiose but not by thiophenyl beta-glucoside (TPG). With the exception of four strains isolated in Japan, all strains of B. subtilis tested possess an inducible phospho-beta-glucosidase activity, beta-methyl glucoside, cellobiose, and TPG acting as inducers. S. aureus strains possess phospho-beta-glucosidase A but not phospho-beta-glucosidase B, whereas most S. albus strains show no detectable phospho-beta-glucosidase activity. The prompt fermentation of beta-methyl glucoside by S. aureus strains could serve as an additional criterion for their differentiation from S. albus. A comparative investigation of the active uptake of (14)C-TPG showed that a Streptococcus group D strain and a B. subtilis strain posses two inducible permeases with characteristics similar to the beta-glucoside permeases I and II of Enterobacteriaceae. In S. aureus, TPG is accumulated by a constitutive permease with high affinity for aromatic beta-glucosides and glucose. The active uptake of TPG by S. aureus appears to depend on the activity of the phosphoenol pyruvate-dependent phosphotransferase system.  相似文献   

17.
Genome conservation in isolates of Leptospira interrogans.   总被引:11,自引:3,他引:8       下载免费PDF全文
Reference strains for each of the 23 serogroups of Leptospira interrogans yielded different pulsed-field gel electrophoresis patterns of NotI digestion products. This was also the case for the 14 serovars belonging to serogroup Icterohaemorrhagiae (with one exception). The NotI restriction patterns of 45 clinical leptospiral isolates belonging to serovar icterohaemorrhagiae were analyzed and compared with those of type strains. No differences were observed between isolates from countries of different continents, namely, France, French Guiana, New Caledonia, and Tahiti. The pattern was indistinguishable from that of the reference strain of serovar icterohaemorrhagiae.  相似文献   

18.
The present work shows that choline-containing phospholipids (lysophosphatidylcholine and lyso-1-alkyl-sn-glycerophosphocholine) inhibit the adhesion of some strains: Bacterium bifidum 1, B. adolescentis MC-42, B. longum B. 379M, Staphylococcus aureus P 209 and Klebsiella pneumoniae 52. Phosphatidylcholine produces no effect on the adhesiveness of these strains, while platelet activation factor stimulates adhesiveness only in strain S. aureus 209. The stimulating or inhibiting action of phospholipids on the adhesive process of microorganisms depends on the species of bacteria and on the concentration of reagents.  相似文献   

19.
During the course of screening new T-H-2 region congenic strains of mice constructed from the C57BL/6 and B6-H-2k strains, a new cell surface polymorphism, designated dtc-1, was identified by cell-mediated lympholysis techniques. The dtc-1 antigen can be found on both Con A- and LPS-stimulated lymphoblasts, peritoneal macrophages, and SV40-transformed mouse embryo fibroblasts. Lysis of dtc-1+ targets by CTL is H-2Dk restricted. All inbred strains tested are dtc-1+, with the exception of the B6-H-2k strain, which is dtc-1-, and several congenic strains directly derived from B6-H-2k. Because B6/Boy and AKR/Boy, the parents of the B6-H-2k strain, are dtc-1+, the dtc-1- phenotype may be the result of mutation in the locus specifying the cell surface molecule that carries this antigen. Segregation analysis of the dtc-1+/dtc-1- polymorphism demonstrated that this locus is not linked to T or H-2. The dtc-1 antigen thus identifies yet another cell surface polymorphism and adds another immunologically defined genetic marker to the murine genome. Furthermore, the dtc-1 system indicates the need for reevaluation and restandardization of congenic strains of mice derived from the B6-H-2k congenic strain.  相似文献   

20.
Adult cabbage root flies (Delia radicum) from three Danish localities were diagnosed microscopically for the natural prevalence of Strongwellsea castrans, Cystosporogenes deliaradicae, and Bacillus thuringiensis. C. deliaradicae was significantly coprevalent with S. castrans. B. thuringiensis sporangia were diagnosed in the hemolymph in two D. radicum which were also infected with S. castrans and proved to belong to serovar aizawai and serovar balearica. The biological characterization of S. castrans proved that at 17.5 degrees C flies developed an abdominal hole 7.9 days (mean) after infection and that 5.7 days (mean) passed from the emergence of the hole to the death of the infected host. No mortality effect among D. radicum subjected to B. thuringiensis serovar aizawai, balearica, and kurstaki isolates was detected. RAPD with DNA proved that six B. thuringiensis serovar balearica isolates (all from the same fly) were indistinguisable. This indicates that proliferation of B. thuringiensis in the abdomen of an S. castrans-infected D. radicum may be due to just one genotype. The profiles of one isolated aizawai strain did not correspond to the profiles of other serovar aizawai strains used for comparison. The biological significance of the interaction between the involved pathogens is discussed.  相似文献   

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