Acta pathologica et microbiologica Scandinavica. Section B, Microbiology最新文献

Whole cells of Neisseria meningitidis have been found to utilize exogenous radioactive hypoxanthine, guanine and xanthine. When hypoxanthine was the precursor, the pools of both the adenine and the guanine 5'-ribonucleotides were labelled. Guanine and xanthine were utilized with labelling of the pool of the guanine 5'-ribonucleotides only. Crude extracts from N. meningitidis were found to have activities corresponding to hypoxanthine phosphoribosyltransferase (EC 2.4.2.8) and another phosphoribosyltransferase which seems to exhibit specificity for guanine and xanthine. Crude extracts phosphorylated guanosine 5'-monophosphate to guanosine 5'-triphosphate in the presence of adenosine 5'-triphosphate (ATP) and MgCl2.

The reproducibility of a polyvalent Pseudomonas aeruginosa antigen (St-Ag) composed of a mixture of antigens from 4 O groups of this bacterium has been studied. Ten batches of St-Ag were produced, and each of these and each of the 10 batches of antigens from the 4 strains of P. aeruginosa were compared with St-Ag batch 1 by means of quantitative immunoelectrophoretic methods and a polyvalent antiserum (St-Ab) raised against St-Ag. Fifty-three of the 55 antigens of St-Ag were stable and could be reproduced with reasonable precision in all 10 batches, and 3 of the 4 strains of P. aeruginosa were stable in antigen composition in all batches. One of the strains (0-5A) had lost 2 antigens in the last 5 batches, and the concentrations of 7 other antigens were simultaneously changed, reflecting a smooth-rough dissociation. The disappearance of the 2 antigens in the latest 5 batches of 0-5A was also reflected in similar changes in the antigen composition of the latest 5 batches of St-Ag.

The occurrence of antibodies against antigens prepared from strains representing 13 O groups of Pseudomonas aeruginosa and against a polyvalent Ps. aeruginosa antigen (St-Ag) has been investigated in sera from 100 patients. By means of fused rocket immunoelectrophoresis with intermediate gel it was found that the humoral immune response against Ps. aeruginosa resulting in precipitating antibodies will be detected by St-Ag as well as by any other of the antigen samples investigated. Six of the sera contained group-specific antibodies which were revealed by only one of the antigen samples used and not by St-Ag. These six sera were further studied by means of various quantitative immunoelectrophoretic methods using St-Ag as well as antigens prepared from the infecting Ps. aeruginosa strain in the patient concerned. In all six sera, only one extra precipitin could be detected using antigens prepared from the homologous strain instead of St-Ag. This extra precipitin corresponded presumably to group-specific O-antigens not included in St-Ag. In sera from patients, these group-specific antibodies were always accompanied by antibodies against antigens common to all strains of Ps. aeruginosa.

Guinea pig antisera against Herpes simplex virus (HSV) types 1 and 2 were compared in neutralization tests and crossed immunoelectrophoresis. It was found that the HSV type specific neutralization of guinea pig antisera could be associated with the precipitating activity to HSV type 1 and 2 glycoproteins.

A passive haemolysis test for the determination of antibodies against rubella virus haemagglutinin is presented. According to this method, the principle of radial immunodiffusion techinque is applied. Rubella haemagglutinin-coated chick erythrocytes in the agarose gel were lysed by the diffusing positive sera of complement at 37 degrees C. The passive haemolysis test was compared with the conventional haemagglutination inhibition method, and the diameter of the haemolysis zones was shown to be a direct measure of the quantity of antibody added to the well. A plot of the log (HI titre) against the zone diameter gives a straight line. There is no need to remove nonspecific haemagglutination inhibitors. However, all serum samples must be inactivated at 56 degrees C for 30 minutes before testing. Tests of 200 serum samples from healthy women showed a good correlation between the haemagglutination inhibition titre and the antibody titre determined by the passive haemolysis technique. Twenty-one samples with a haemagglutination inhibition titre less than 10 were also negative in the passive haemolysis test. With the exception of one, all sera with a positive haemagglutination inhibition titre showed a positive haemolysis reaction. The method was found to be as specific and as sensitive as the haemagglutination inhibition test. In addition, the technique is rapid and simple for quantitative studies of antibodies against rubella virus.

The catabolism of glucose in selected Neisseria species was studied by radiorespirometry. The Entner-Doudoroff and pentose phosphate pathways were operating in all species, the greater part of the substrate being routed through the former, somewhat dependent on the medium used. Acetate was oxidized via the tricarboxylic acid cycle. In all species, a fraction of the triose was recycled through fructose phosphates to glucose 6-phosphate. Phosphate inhibited the oxidation of acetate. In media devoid of phosphate and sodium (N. meningitidis and N. gonorrhoeae) or of phosphate and potassium (other saccharolytic Neisseria), the conversion of triose to pyruvate was inhibited. In these media the catabolism of glucose proceeded slowly, and no substrate was used for biosynthetic purposes. The results point to a difference in the regulation of glucose metabolism in pathogenic and non-pathogenic Neisseria.

Serologic cross-reactions between 26 strains of Pseudomonas aeruginosa representing 13 O groups were studied by various quantitative immunoelectrophoretic techniques. As reference system was used a polyvalent Ps. aeruginosa antigen and a corresponding rabbit antiserum. Fifty-one (93 per cent) of the 55 Ps. aeruginosa antigens in the reference system were present in all the strains and corresponding antibodies in the reference system could be completely absorbed by all the strains. Complete cross-reactivity was also found between antigens of the reference system and 3 of the 4 antigens present only in some of the strains. The last of the 4 antigens not present in all the strains could only absorb part of the corresponding antibodies in the reference system. Absorption experiments with whole heat-killed bacteria indicate that this antigen is related to the O group antigens of Ps. aeruginosa. None of the antigens of the reference system were related to the mucoid substance produced by some strains of this bacterium.

The purpose of the present investigation was to study the occurrence of Yersinia enterocolitica (Y.e.) among small rodents and shrews (Soricidae) from Norway, Sweden and Finland. During a period of one year beginning in the autumn of 1973, animals from seven localities were examined. Twenty-four strains of Y.e. were isolated from 551 small rodents. Isolations were made from six of the seven localities and from six of the nine small rodent species examined. Pooled faeces samples from 397 animals yielded 12 strains. Faeces from 154 small rodents were separately investigated: Twelve (8 per cent) of these animals harboured Y.e. No isolations were made from 52 shrews. Most of the strains showed antigenic relationship to O-serotypes previously reported from untreated drinking water in Norway. Two strains were antigenically related to O-serotype 3 but differed biochemically from the strains found in man and swine. The results indicate that Y.e. has a widespread distribution among small rodents in Norway, Sweden and Finland.

Production of the common enterobacterial antigen (CA) by strains of Yersinia enterocolitica (Y.e.) serotypes 3 and 9 (Winblad), by strains of 5 different Y.e. serogroups (Wauters) and various other bacteria was examined. Antibody against CA was raised by immunization of rabbits with E. coli O 14. Extract prepared from S. typhimurium was used for the sensitization of sheep erythrocytes with CA. Absorption and haemagglutination inhibition experiments showed that CA could be detected in heat extracts from all Y.e. strains examined, and in that from Yersinia pseudotuberculosis. CA was not detected in extracts from Pasteurella multocida, Francisella tularensis, Brucella abortus, Acinetobacter calcoaceticus or Pseudomonas aeruginosa. Anti-CA antibodies could not be demonstrated in serum from rabbits immunized with Y.e. bacteria, but were demonstrated in serum from rabbits immunized with a CA-containing fraction of the Y.e. extract. The possibility of participation of anti-CA antibody in indirect haemagglutination tests for detection of antibody to Y.e. O antigens is emphasized.

Light and electron microscopic examination of portio biopsies from eleven patients with trichomoniasis vaginalis revealed in four patients clusters of cells of T. vaginalis (T. vag.) which were attached to the vaginal mucosa. The minimum gap between adjacent trichomonad cells was the size of gap junctions (2 nm). Cells of T. vag. invaded superficially located epithelial cells but did not penetrate to the deeper cell layers of the epithelium. The latter, however, were frequently infiltrated with neutrophilic granulocytes. Contact between cells of T. vag. and neutrophils was not observed. Trichomonads which were attached to epithelial cells contained a dense network of cytoplasmic microfilaments in the part of the cell which came into contact with the epithelium. The remaining part contained the organelles normally seen in T. vag.. Endocytotic cell activity of amoeboid T. vag. occurred from the free cell surface only. A cell coat on the cell membrane--formed by bristles--was confined mainly to pinocytotic invaginations. Glycogen granules which were absent from the larger part of the epithelium were densely packed in the trichomonad cells. The findings in this study indicate that the interaction between the cells of T. vag. and the vaginal epithelium takes place primarily at a distance probably by means of substances released into the vaginal fluid, and secondly by a direct cell contact mechanism.