J. Brückler

Wirkung bakterieller neuraminidasen auf transferrin vom menschen, rind und kaninchen

Abstract Transferrin from humans, type CC, was split by various bacterial neuraminidases into five bands which were detectable by disc electrophoresis. These bands appeared simultaneously in one electrophoretogram with neuraminidase of Pasteurella multocida and Pasteurella hemolytica and subsequently in a series of electrophoretograms with neuraminidases of Vibrio cholerae and Diplococcus pneumoniae. Transferrin from rabbits was split by all of these neuraminidases into three bands. Transferrin from cattle (type AA) after treatment with the neuraminidases showed a reduced electrophoretic mobility. At the same enzyme activities the neuraminidases had different effects upon the transferrins. However, at respectively high concentrations the neuraminidases liberated all of the bound sialic acid from the transferrins.

Antiphagocytic factors of Staphylococcus aureus

Abstract Several staphylococcal substances could interfere with phagocytosis, imparting a definite advantage on Staphylococcus aureus in the initial phase of infection. Leukocidins were shown to damage mainly granulocytes and macrophages. Clumping-factor, by direct reaction with fibrinogen, induced clumping of the staphylococci in plasma. This impaired phagocytosis. The increased virulence of encapsulated staphylococci was caused by a delay in chemotaxis and phagocytosis. Apparently encapsulation prevented activation of C3, by the staphylococci.

Purification of oligomeric staphylococcal α-toxin by affinity chromatography on digitonin-sepharose

An effective concentration of alpha-toxin from Staphylococcus aureus Wood 46, directly from the culture supernatant, could be achieved by adsorption on digitonin-sepharose and elution with 3 mol/l sodium thiocyanate (NaSCN). The toxin was further purified by gelchromatography. The purified product yielded 1 single protein band upon SDS-polyacrylamide electrophoresis. It was nonhemolytic, but reacted with anti-alpha-toxin under complement fixation. Dialysis against 0.14 mol/l NaCl with hydrophobic amino acids partially reactivated the alpha-hemolytic activity of the toxin. Ultracentrifugal analysis yielded sedimentation coefficients for the purified toxin of approximately 3,7 S when dissolved in 3 mol/l NaSCN and of about 12 S after dialysis against 0.14 mol/l NaCl (Table 1). The spontaneous oligomerization of the alpha-toxin during dialysis against 0.14 mol/l NaCl possibly resulted from a change in configuration induced by its adsorption to digitonin-sepharose.

Inhibition of staphylococcal α-hemolysis by monoclonal antibodies against oligomer 12 S α-toxin

Abstract Oligomer 12 S α-toxin as well as 3 S α-toxoid of Staphylococcus aureus induced the formation of monoclonal antibodies (mabs). Mabs against the 12 S α-toxin could be demonstrated in 31 and those against 3 S α-toxoid in 18 of 120 hybrid cell colonies. Each of these mab-preparations reacted with 12 S, 3 S α-toxin and 3 S α-toxoid. The reactions were more pronounced with the homologous than the heterologous toxin preparations. Mabs against 12 S α-toxin inhibited the hemolytic effects of native 3 S α-toxin as well or better than the respective polyclonal antisera.

Release of some staphylococcal enzymes and toxins under the influence of size of inoculum and time of incumbation

Abstract With increasing size of inoculum (0.025, 0.25, 2.5 g of wet Staphylococcus aureus per 100 ml broth) maximal coagulase-activity (256–512 U/ml) was detected in the supernatant after 30 min-2 hr of incubation at 37°C. Alpha- and beta-hemolysins appeared later (after 8–24 hr of incubation). Acid/alkaline phosphatase could be demonstrated from the beginning of incubation, but their maximal activity in culture supernatant could be demonstrated after 8–24 hr of incubation (Table 1). Thus, size of inoculum and time of incubation have a greater significance in the optimal production of some staphylococcal substances than generally assumed.

Lipase und Phospholipase C von Staphylococcus aureus verschiedener Herkunft I. Nachweis und vorkommen

Abstract Lipase and phospholipase C from Staphylococcus aureus of different origin were demonstrated qualitatively by agar diffusion on tributyrin-and lecithinagar. On test media with either 0,3% Na-azide or 0,3% KCN lipase-activity was not inhibited, phospholipase C, on the other hand, completely blocked (Table 1, Fig. 2). In this manner a tentative differentiation was possible between lipase and phospholipase C. For the quantitative determination of lipase the hydrolysis of p-nitrophenylpalmitate proved to be most useful (Fig. 1). S. aureus-cultures of human origin produced more often and more actively lipase and phospholipase C than those from cattle (Table 2).

„Clumping-Factor“-Reaktionen von Staphylococcus aureus verschiedener Herkunft in Plasma- und Fibrinogenpräparationen1

Abstract The clumping-factor (CF) test in microtiter-plates proved suitable for the preliminary identification of Staphylococcus aureus , provided a “susceptible” plasma- or fibrinogen-preparation had been applied (Table 1). Thus, all of 100 S. aureus -cultures from humans gave strongly positive CF-reactions with plasma from humans, rabbits, pigs, cattle, and dogs as well as with fibrinogen-solutions from humans and cattle. Equally, all of 100 S. aureus -cultures from cattle clumped in plasma from pigs, cattle and humans. All of the 50 S. aureus -cultures from dogs were CF-positive in plasma from dogs, humans and horses. Only part of the CF-positive S. aureus -culture reacted with plasma from sheep and goats.

Release of Coagulase from Staphylococci

Immediately after inoculation with coagulase-positive staphylococci the coagulase-activity increased significantly in various culture media. The increase was much higher than the calculated coagulase-activity added with the inoculum (table 1). It appears that this release offers a possibility for the efficient production of coagulase prior to purification.

[Measurement of alpha 2-macroglobulin in human sera by quantitative inhibition of an acid staphylococcal protease (author's transl)].

Abstract Concentrations of α 2 -macroglobulin could be determined in the sera of 215 blood donors and 94 patients with various internal diseases by quantitative inhibition of an acid protease from Staphylococcus aureus , M 135 (fig. 1, 2). The determinations agreed closely with those obtained by immunodiffusion (tab. 1, fig. 3). However, the α 2 -macroglobulin-measurements by the protease method required only 4 h and 50 μl serum. This procedure would also be suitable for the determination of α 2 -macroglobulin in sera from experimental and domestic animals.

Lipase und Phospholipase C von Staphylococcus aureus verschiedener Herkunft II. Reinigung und charakterisierung

Abstract Lipase and phospholipase C from Staphylococcus aureus could be isolated by gel filtration on Sephacryl® S 200 (Fig. 1a, b) and completely separated by refiltration under the same conditions. Isoelectric focusing gave maximal enzyme-activities for lipase at pH 8.6 and 9.5 and for phospholipase C at pH 7.4 (Fig. 2). Thin-layer chromatography revealed that the reaction products in lecithin agar of the phospholipase C-preparations from S. aureus and Bacillus cereus were identical (Table 1).