摘要:

The somatic antigens of eightRhizobium melilotistrains were characterized by indirect enzyme-linked immunosorbent assay (ELISA) carried out in microtiter plates. Washed cells were bound by evaporation of cell suspension in plate wells at 85 °C. The antigenic characterization was based on determinations of the selective removal of antibodies from antisera against the strains by extensive reciprocal adsorptions with heterologous cells. Four of the strains were found to possess distinctive antigens and a total of seven different combinations of antigens were found among the eight strains. One pair of the strains was not distinguishable by the assay used.

ISSN:0008-4166    

DOI:10.1139/m84-171

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Twelve lectins, 11 of plant and 1 of animal origin, were tested against the 28 serovars ofBacillus thuringiensisto study their agglutinating specificities. Except for the sialic specific lectin fromLimulus polyphemus, tube agglutination assays were performed using lectin concentrations of 10, 50, and 100 μg against 0.2 mL of 109 cells/mL in a final volume of 1.0 mL. The agglutination studies with theLimuluslectin were performed using 10 and 50 μg of lectin. Tubes were incubated overnight at room temperature (25 °C) and observed for aggutination patterns. Ten of the 28 serovars were individualized according to their ability to bind with various lectins. The study shows that the various serovars have different carbohydrate residues which indicates that the O-somatic antigens differ.

ISSN:0008-4166    

DOI:10.1139/m84-172

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Staphylococcus aureusMF31 can grow at 46 °C, 2 °C above its normal maximum temperature of growth if 1 MNaCl is added to the medium. In the present work we show that monosodium glutamate, proline, threonine, aspartic acid, and betaine (in order of decreasing effectiveness) also enabled cells to grow at 46 °C. Cells grown at 46 °C in he presence of salt (protected or P cells) accumulated glutamate more rapidly than cells grown at 37 °C without salt (normal or N cells) and contained an increased amino acid pool. The principal constituents of this pool were dicarboxylic amino acids and proline. Turbidimetric evidence suggests that NaCl caused plasmolysis inS.aureus. The P cells, although grown in 1 MNaCl, had about the same Cl−and K+content as the N cells grown without added NaCl. P cells had increased heat resistance but high concentrations of CaCl2in the heating menstruum reduced theirD55value from a maximum of 214 min to < 30 s. We suggest that growth at 46 °C in 1 MNaCl can be explained, in part at least, by the increased amino acid pool internal to the cell and the external osmotic support given by Cl−anions excluded by the cell.

ISSN:0008-4166    

DOI:10.1139/m84-173

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

The survival of microorganisms of theMycobacterium avium,M.intracellulare, andM.scrofulaceum(MAIS) complex was evaluated after various soil and water decontamination regimens. Survival was reduced by growing cells in natural waters compared with laboratory media and by inclusion of malachite green in media as an antifungal agent. Decontamination with benzalkonium chloride, while reducing survival significantly less than 1% NaOH, failed to eliminate many fungi. Recovery from soil was further reduced by transfer losses and by irreversible cell adsorption onto particulates.

ISSN:0008-4166    

DOI:10.1139/m84-174

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Pseudomonas aeruginosaelastase, but not alkaline protease, degraded pooled, normal, human IgGin vitroand this degraded IgG lost its protective effect when used to treat burned,P.aeruginosainfected mice. Plasma IgG levels in burned, uninfected mice declined immediately postburning, but remained relatively constant thereafter; the levels in burned,P.aeruginosainfected mice continued to decline until death ensued. Infection of burned mice with an elastase+strain caused the IgG decline, while infection with an elastase−strain did not, suggesting that elastase production caused thein vivodecline in plasma IgG. Local treatment with the protease inhibitor α2-macroglobulin, of burned mice infected with an elastase+organism, reduced the IgG decline observed in control mice. These data support the hypothesis thatP.aeruginosaelastase acts as an IgG protease bothin vitroandin vivoand gives insight into how this enzyme may act as a virulence factor inP.aeruginosa.

ISSN:0008-4166    

DOI:10.1139/m84-175

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

An acid forest soil (pH 3.9 – 4.4) from an undisturbed mixed oak stand in southern Indiana was examined for the occurrence of ammonia- and nitrite- oxidizing chemoautotrophs. Populations of both nitrifiers were detected in pH 7 most-probable-number (MPN) autotrophic media, and aNitrosospirawas isolated from highest dilution ammonia oxidizer MPN tubes. Populations of nitrite oxidizers were 10 to 1000 times higher than those of ammonia oxidizers. In pH 4.0 MPN media, ammonia oxidation was slight and unsustainable on 10% transfer to fresh medium, whereas nitrite oxidation was vigorous and sustainable. In pure culture theNitrosospiraisolate (Np IO1a) was completely inhibited by nitrapyrin at 5 μg mL−1, tolerant of 1.0 and 10.0 mMchlorate, and capable of growth only at pH 6.2 and above. Fluorescent antibodies raised against Np IO1a were used to confirm the predominance of Np IO1a in all MPN series examined. These results suggest that autotrophic ammonia oxidizers may be restricted to circumneutral microsites in this acid soil, whereas autotrophic nitrite oxidizers may not be limited to such sites.

ISSN:0008-4166    

DOI:10.1139/m84-176

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Bacteroides endodontalis, a newly described asaccharolytic black-pigmentedBacteroides, along with the other two recognized species of this group (B.gingivalisandB.asaccharolyticus) were studied for their susceptibility to various dyes and inhibitory agents and for some of their enzymatic activities to facilitate differentiating between them.Bacteroides endodontalisresemblesB.asaccharolyticusphysiologically except for the fact that the former cannot grow on media containing methylene blue, neutral red, or 3% sodium choride, whereasB.asaccharolyticuscan. On the other hand,B.endodontalisandB.gingivaliscan grow on a medium containing Congo red whileB.asaccharolyticuscannot.

ISSN:0008-4166    

DOI:10.1139/m84-177

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Hemorrhagic fever with renal syndrome is endemic in most parts of the world. The etiological agent in known as Hantaan virus. More than 2000 Canadian sera from all age groups and provinces were tested for the presence of antibody to this virus by the indirect immunofluorescent antibody technique. The frequency of seropositivity ranged from 0.3 to 4.0%, with the national average being 1.4%. Newfoundland and New Brunswick in the Atlantic region had the highest positivity, being higher than hyperendemic areas in Korea. The inland provinces of Ontario, Manitoba, and Alberta had only 0.5% positives to Hantaan virus. In contrast, approximately 1.5% of sera from Saskatchewan, Quebec, and British Columbia were positive. No correlation in positivity was found between geography or sex, but positivity did increase with age. The highest titres were found in the group aged 65 to 93 years.

ISSN:0008-4166    

DOI:10.1139/m84-178

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Twenty-one tailed phages with icosahedral heads belong to theMyoviridae,Siphoviridae, andPodoviridaefamilies and to four morphological types. Type AU, with 10 phages, has a contractile tail and is morphologically identical with coliphage P2. Lysates contain contracted tail sheaths assembled end-to-end and abnormal structures with long tails and multiple tail sheaths. Types C-2 and 32, with one and three phages, respectively, have long, noncontractile tails. Type 22 includes seven phages, has a short tail, and resembles coliphage T7. Our results agree with previous biological data and suggest that types AU, C-2, 32, and 22 correspond to four different phage species.

ISSN:0008-4166    

DOI:10.1139/m84-179

出版商:NRC Research Press    

年代:1984

数据来源: NRC

摘要:

Vibrio choleraestrains of the 01 serovar, isolated from both clinical and environmental sources, had a much lower frequency of plasmid carriage (2/112 = 2%) than clinical and environmental non-01 serovar isolates (46/187 = 25%). The cryptic plasmids found in non-01 strains were all of low molecular weight and were shown by hybridization analysis to consist of two unrelated subgroups. Each subgroup was observed to be present in strains isolated from both clinical and environmental sources. One 01 serovar (ATCC 14033) carried a small cryptic plasmid, belonging to one of these plasmid groups, while a second (25728) contained a high molecular weight multiple antibiotic resistance plasmid which did not hybridize to either plasmid subgroup.

ISSN:0008-4166    

DOI:10.1139/m84-180

出版商:NRC Research Press    

年代:1984

数据来源: NRC