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H Blobel

Publications and source records attributed to H Blobel.

At least 91 records · Page 5Linked to original sources
PubMed1981

[Protein A-activity of Staphylococcus hyicus in comparison to protein A of Staphylococcus aureus (author's transl)].

Protein A (PA)-Activity was demonstrated in 44 (93.6%) of 47 Staphylococcus hyicus-cultures. PA from S. hyicus, as well as PA from S. aureus, could be released by extraction with concentrated formic acid or by treatment of the staphylococci with lysostaphin. PA was also demonstrable in the culture medium. Purification of PA from S. hyicus and S. aureus could be achieved by affinity-chromatography on IgG-Sepharose. In Ouchterlony-tests both PA-preparations gave single lines of identity with normal sera from man, pig, dog and guinea pig (Fig. 1). Immunoelectrophoretic analysis indicated a significantly faster migration towards the anode for PA from S. hyicus than PA from S. aureus (Fig. 2). Isoelectric focusing revealed maximal activity for PA from culture supernatant of S. hyicus about pH 4.3 and for that of S. aureus at pH 5.0 (Fig 3). Gelchromatographic experiments indicated a lower molecular weight for PA from S. hyicus than for PA from S. aureus (Fig. 4).

Animals↗
PubMed1981

[Antigenic effects of Staphylococcus aureus with modified surface-structures (author's transl)].

Antigenic effects of preparations from Staphylococcus aureus ATCC 31243 and Rd 4 (Table 1) with partially different activities of "clumping factor" (CF) and protein A (PA) were compared (Table 2). The (3 h, 60 degrees C) heat-inactivated (hi) as well as the guanidinium-chloride-extracted (gu) staphylococci retained full activity of CF and PA. Acetylation with N-acetylimidazole inactivated completely CF and partially PA. Treatment of the staphylococci with pronase (pron) removed CF and PA. The hi-, gu- and pron-preparations of both S. aureus strains had similar antigenic properties which differed from those of the acetylated staphylococci, when antisera against all preparations were examined in the agglutination (Table 3) and "growth"-agglutination-tests (Fig 1). Acetylation apparently affected the staphylococcal surface to a larger extent than the other procedures applied in these studies.

Acetylation↗
PubMed1981

[Clumping-factor-reactions of Staphylococcus aureus of different origin in plasma- and fibrinogen-preparations(author's transl)].

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.

Agglutination↗
PubMed1981

[Production of coagulase from Staphylococcus aureus of different origin (author's transl)].

Cultivation of Staphylococcus aureus in a fermenter significantly improved production of coagulase (Fig. 1,2,3). Optimal coagulase-activity was reached in the culture supernatant after inoculation with 8 x 10(9) colony-forming S. aureus per ml of brain heart infusion broth and 20 min at 37 degrees C. At this time most of the other enzymes and toxins (particularly protease and staphylokinase) had not been formed or only in small amounts. Characterization of coagulases from respectively 5 S. aureus-cultures from humans, cattle and dogs revealed molecular weights between 56800 and 71000, and isoelectric points between 5.4 and 6.4 (table 1).

Animals↗
PubMed1980

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

Concentrations of alpha 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 alpha 2-macroglobulin-measurements by the protease method required only 4 h and 40 microliter serum. This procedure would also be suitable for the determination of alpha 2-macroglobulin in sera from experimental and domestic animals.

Humans↗
PubMed1980

[Lipase and phospholipase C from Staphylococcus aureus of different origin. I. Determination and occurrence (author's transl)].

Lipase and phospholipase C from Staphylococcus aureus of different origin were demonstrated qualitatively by agar diffusion on tributyrin- and lecithin agar. 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-nitrophenyl palmitate 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).

Animals↗
PubMed1980

[Demonstration of species-specific teichoic acids in staphylococcal species with reference to protein A activity (author's transl)].

Serologically different teichoic acids could be demonstrated as polysaccharide antigens in staphylococcal species by immunodiffusion (Fig. 1) and counterimmunoelectrophoresis (GSE, Fig. 2). Staphylococcus aureus contained polysaccharide A, S. epidermidis polysaccharide B, S. saprophyticus polysaccharide A beta C, and S. hyicus polysaccharide C (Table 2). These polysaccharides were specific for staphylococcal species and could not be found in micrococci. The antigen preparations for the GSE were autoclaved suspensions of the staphylococcal and micrococcal cultures. The specific antisera (Table 1) were obtained after absorption with pronase-treated staphylococcal reference strains. Treatment with pronase removed protein A from the absorbing staphylococci. In this manner the "nonspecific" loss of specific antibodies was prevented. This would have occurred by the attachment of the Fc-component of immunoglobulin G to protein A of S. aureus. The precipitin-lines contained the polysaccharide-antigens and not protein A.

Antigens, Bacterial↗
PubMed1980

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.

Bacteriological Techniques↗
PubMed1980

[Lipase and phospholipase from Staphylococcus aureus of different origin. II. Purification and characterization (author's transl)].

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).

Animals↗
PubMed1979

[Improved method for the demonstration of protein A of Staphylococcus aureus (author's transl)].

Protein A (PA) could be extracted completely from Staphylococcus aureus by treatment with concentrated formic acid. This led to the development of a semi-quantitative determination of PA by hemagglutination (fig. 1). The treatment with formic acid yielded PA more effectively than the commonly used extraction by boiling (table 1). It could be conducted directly on a loopfull of staphylococci obtained from blood agar. It required no additional cultivation in a fluid medium. Most suitable for the hemagglutination was a commercial preparation of Rh-positive human erythrocytes, blood group O, loaded with Rh-antibodies from humans. This relatively stable preparation had also a higher susceptibility for PA in the slide-test and served for a better detection of PA-positive staphylococci (table 2).

ABO Blood-Group System↗
PubMed1978

[Qualitative and quantitative determinations of staphylokinase-activity (author's transl)].

Staphylokinase (SAK)-activated plasminogen reacted specifically with nitroanilide (N-benzoyl-DL-lysine-4-nitroanilide) to form intensively yellow 4-nitroaniline. This reaction did not occur with staphylococcal proteases. For qualitative SAK-determinations nitroanilide was incorporated in an agar medium. SAK diffused into the medium and caused a distinct change in color from white to yellow. For quantitative SAK-determination the conversion of colorless nitroanilide to yellow 4-nitroaniline was recorded photometrically at 405 nm. The optical density correlated well with SAK-activity of preparations with different degrees of purity (fig. 1, 2). Another quantitative procedure for SAK-activity could be conducted with fibrin in microtiter-plates (Fib-MTT). In this method, after 2-fold dilutions of SAK-preparations fibrinogen (stained blue with astrazonblue) and subsequently thrombin were added. SAK-activity was indicated by lysis of the blue-colored fibrin clots in the microtiter-plates (fig. 3). The Fib-MTT was particularly suitable for measuring wide ranges of SAK-activities.

Fibrin↗