Zentralblatt für Bakteriologie, Mikrobiologie und Hygiene. Series A: Medical Microbiology, Infectious Diseases, Virology, Parasitology最新文献

A total of 102 Neisseria gonorrhoeae isolates from Munich with known nutritional requirements were examined for lectin agglutination patterns using Taxonolectin panels containing 14 different plant originated lectins with known specificity. 29 different lectin agglutination patterns were found (in comparison auxotyping showed 17 different groups). All strains reacted with Concanavalin A and Trichosantbes kinlowii and did not show positive reactions with Limax flavus and Ulex europaeus I. 49 Isolates (48%) had lectin agglutination patterns associated with only four lectin groups (in comparison the four major auxo typing groups comprised 58 (57%) of the tested isolates). A correlation between auxotype and lectin agglutination pattern could not be demonstrated. Reproducibility of lectin agglutination patterns was excellent.

The safety of patients asks for stringent standards when fixing limit values of the minimal inhibition concentration (MIC) in mg/1. It should be possible to recognize resistant bacterial strains with a low error on the basis of the recommendations of the bacteriological laboratory which are eventually important for therapy. Attention is drawn to the use of recognized methods such as DIN 58940 and 58944 and the participation in interlaboratory studies. Only such bacteria should be interpreted as „susceptible“ whose MIC's are reliably below or, which is even better, much below the generally recognized average blood and tissue levels. Thus the break-points for the rating “susceptible” must be within the range of low variation. As a resalt, a few strains more would come within the “moderately susceptible” range. This would not exclude them from being selected if chemotherapy is performed with a correspondingly higher dosage (provided it is tolerated). Information on the chances of a success of therapy is improved in this way. A generous interpretation of pharmacokinetic data will in the end be more to the patient's detriment. In addition, there are numerous factors determining success or failure of therapy which cannot be established in vitro so that it is advisable to fix laboratory parameters in a stringent manner like that applied in the annexes (evaluation steps) to parts 3 and 4 of DIN 58940.

It has been demonstrated earlier that the genome of the porcine circovirus (PCV) isolated from virions is a circular single-stranded DNA (ssDNA). This report describes the isolation and characterization of PCV-specific DNA from infected cell cultures. Two types of doublestranded DNA (dsDNA) were observed which behaved like supercoiled and relaxed circular molecules, respectively. Both types of dsDNA displayed infectivity in transfection experiments and are regarded as replicative forms (RF) of the viral genome. In addition to complete single-stranded viral genomes and RF DNA molecules, PCV-specific subgenomic fractions of DNA molecules with a sedimentation coefficient of about 5 S were isolated from infected tissue culture cells. This 5 S DNA was also isolated from purified virions. It is single-stranded and represents a defined region of the viral genome.

Purified preparations of lipopolysaccharides (LPS) extracted from two different strains of Leptospira interrogans have been electrophoretically analyzed in order to determine their location at the level of outer envelope (OE). Evidence has been collected for the presence of some LPS fractions in the OE, suggesting that a part of this molecule is embedded in the membrane structure. The serological specificity of the LPS has been in addition tested by means of monoclonal antiserovar antibodies (Moabs); the results indicated that the LPS structure is endowed of the immunodeterminants of the serovar. The remarkable relevance of this finding for the Leptospira taxonomy is discussed.

Die aus Leptospira interrogans Serovar copenhageni bzw. hardjo isolierten und gereinigten Lipolysaccharide (LPS) wurden elektrophoretisch untersucht, um damit ihre Lokalisation in der äußeren Hülle zu bestimmen. Der Nachweis von LPS-Fraktionen in der äußeren Hülle legt die Annahme nahe, das ein Teil des Moleküls in die Membran-Struktur eingebaut ist. Mittels monoklonaler, serovarspezifischer Antikörper wurde gezeigt, daß LPS zu der immundominanten Struktur der Serovare beiträgt.

Cholera disease can be induced in the rabbit by duodenal inoculation (DI) of Vibrio cholerae organisms after ligation of the cecum (C) (DIC model). When ligation of the cecum is omitted, no disease symptoms develop. In contrast, the animals are primed which becomes apparent as vibriocidal protection upon challenge with V. cholerae in the DIC model. This protection coincides with high anti-O antigen IgA levels in the bile. The O antigen was shown to be the protective antigen and it must be presented by live organisms. A non-enterotoxigenic mutant of V. cholerae induced protective immunity in the rabbit but was reported to cause mild diarrhea in human volunteers. Looking for alternatives, we applied cholera toxin, known as a mucosal adjuvant, together with killed V. cholerae cells to rabbits. Unfortunately, the minimum adjuvant dose was equal to the minimum toxic dose. A Salmonella typhimurium strain expressing also the V. cholerae O antigen induced systemic rather than local immunity which was not protective. Several Escherichia coli strains were able to elicit a local immune response, but the animal to animal differences were considerable. Therefore, V. cholerae itself was thought to be the most appropriate carrier organism. Some non-enterotoxigenic and auxotrophic mutants of V. cholerae were able to prime and did not show any undesired side-effects in the DIC model. Therefore, further attenuation of non-toxigenic V. cholerae strains by means of stable deletions in nutritional genes seems to be the most promising way to obtain acceptable vaccine candidates.

Pseudomonas aeruginosa is one of the most troublesome human pathogens in the antibiotic consuming era. It produces lectins and lectinoid adhesins as secondary metabolites. The production of these compounds is genetically determined and is highly sensitive to changing environmental conditions. These dictate the type of the lectin produced [“type” variation], the lectin level [“on-off” variation], and its localization [“in-out” variation]. PA-I [galactophilic] and PA-II [fucose and mannose-binding] P. aeruginosa lectins are sensitive to EDTA and exhibit biophysical properties, resembling those of classical plant lectins. They exert similar in vitro biological effects and have an equal applicative potential. Lectin deficient strains and mutants of P. aeruginosa may be used for studies on lectin role in “conditioning” the bacterium lytic and toxic activities in its attacks on cells or macromolecules. The Pseudomonas lectins cofunction with lytic and toxic activities: We suggest that they serve the homing and “condition” the lytic enzyme optimal activity on cellular and macromolecular targets. Namely their role resembles that of “positioning sites” of lytic enzymes and “receptor-binding” domains of powerful microbial, plant and animal toxic or lytic systems [including immunoglobulins, which “condition” the lytic activities of complement and phagocytes], as well as certain hormones, which condition limited key lytic activities, and thereby trigger a cascade of metabolic reactions.

It has been shown that the mere presence of gram-negative bacteria within the kidney parenchyma does not lead to kidney damage. Various accessory manipulations modifying the resistance of the urinary tract should be used to induce kidney lesions. We present the results of our experiments with sterile bacterial filtrate applied accordingly to the technique of Shwartzman phenomenon. This way we produced experimental acute pyelonephritis in rats by an ascending route of infection. A significant pathogenic activity of sterile bacterial filtrate in comparison with saline was shown producing clinically relevant infections of the urinary tract in rats infected by concentrations of E. coli suspensions of 10⁴ and 10⁵ cfu/ml.

Die gram-negativen Bakterien allein rufen in den Nieren von Versuchstieren kaum einen entzündlichen Prozeß hervor. Verschiedene zusätzliche Manipulationen, durch welche die Resistenz des Harnwegsystems modifiziert wird, sind hierzu notwendig. In dieser Arbeil werden die Ergebnisse unserer Versuche mit sterilem bakteriellem Filtrat dargelegt. Nach der Shwartzman-Phänomen-Technik wurde das Filtrat zur Einleitung einer experimentellen Ratten-Pyelonephritis, hervorgerufen durch aszendierende bakterielle Infektion, verwendet Eine signifikante pathogenetische Wirkung des bakteriellen Filtrates gegenüber den Kontrollen mit physiologischer NaCl-Lösung konnte gezeigt werden (p < 0,01). Die auf diese Weise erzeugten klinisch-relevanten Harnwegsinfektionen wurden bei den Ratten durch die Suspensionen von E. coli in den Konzentrationen von 10⁴ und 10⁵ cfu/ml hervorgerufen.

Cell surface antigen was mechanically extracted from encapsulated strain SE-360 of Staphylococcus epidermidis and purified by DEAE-Sephadex A 25 (Cl⁻ form) ion exchange chromatography. This antigen manifested type-specific activity and major sugar constituents were galactose, glucose and N-acetyl-glucosamine at the molar ratio 1.00:9.05:1.65. α-D-glucosyl- and N-acetyl-glucosaminyl-residues were closely correlated to the antigenic determinant. In mice, protection against homologous microorganisms could be achieved by active immunization with thus purified antigen. Type-specific opsonin in rabbit anti-SE-360 serum could also be absorbed.

Das Zelloberflächenantigen des bekapselten Staphylococcus epidermidis-Stammes SE-360 wurde mechanisch extrahiert und mittels DEAE-Sephadex A 25 (Cl⁻-Form)-Ionenaus-tauschchromatographie gereinigt. Dieses Antigen vermittelte eine typspezifische Aktivität. Als hauptsächliche Zuckerbestandteile konnten Galaktose, Glukose und N-Acetyl-Glukosamin in einem molaren Verhältnis von 1.00:9.05:1.65 respektive nachgewiesen werden, α-D-Glukosyl- und N-Acetyl-Glukosaminyl-Bestandteile waren mit der antigenen Determinante eng verbunden. In Mäusen konnte mit diesem Zelloberflächenantigen eine aktive Immunisierung gegen den homologen Staphylokokkenstamm durchgführt werden, auch konnten damit typspezifische Opsonine im Kaninchen-Anti-SE-360-Serum absorbiert werden.

We report a case of bacterial CAPD peritonitis in a 57 year old immunosuppressed woman with renal insufficiency caused by a rare species of the Micrococcaceae, Stomatococcus mucilaginosus.

This uncommon case shows that the presence of gram-positive cocci in pairs, tetrads and clusters forming whitish-gummy colonies should remind us of the possibility of Stomatococcus mucilaginosus.

Beschrieben wird ein Fall einer bakteriellen CAPD-Peritonitis, der bei einer 56jährigen, immunsupprimierten Patientin mit terminaler Niereninsuffizienz auftrat und durch einen seltenen Vertreter der Micrococcaceae (Stomatococcus mucilaginosus) verursacht wurde.

Dieser mikrobiologisch außergewöhnliche Fall zeigt, daß bei grampositiven Kokken, die in Haufen, Tetraden und Paaren angeordnet sind und weiße, gummiartige Kolonien bilden, Stomatococcus mucilaginosus in Betracht gezogen werden sollte.