Enzymo-Serological Comparison of Proteolytic Enzymes Produced by Salmonella Species and Other Enterobacteria

Comparison of Bacillus thuringiensis with other bacillus species based on enzymoserological examinations of their proteolytic enzymes

Investigated strains of Bacillus thuringiensis were all good producers of casein precipitating proteinases (CP-enzymes).

CP-enzymes produced by five strains of B. thuringiensis were serologically compared with enzymes produced by strains of B. cereus, B. licheniformis and B. subtilis. The technique used is a special enzymoserological procedure by which the proteolytic activity is neutralized by specific antisera. A close enzymoserological relationship was demonstrated between B. thuringiensis and B. cereus, while no interspecies cross-reactions occurred between enzymes of these species, and those of B. licheniformis and B. subtilis.

The possibility of undetected transference of B. thuringiensis from bacteriologically treated plant material to animals is discussed in relation to the high degree of similarity between B. cereus and B. thuringiensis.

The in vitro effects of peptide-precipitating lignosulphonic acids on various biologically active substances produced by or with action on microorganisms

The effects of lignosulphonic acids on colicins, coliphages, different antibiotics, ß-toxin of Staphylococcus aureus, lecithinases of Clostridium perfringens and of Bacillus cereus, hemolysins of Bacillus cereus and Escherichia coli, the bactericidal effect of lysolecithin and on specific and naturally occurring serum proteinase inhibitors have been studied. It was found that lignosulphonic acids distinctly inhibit the biological activities tested, with the possible exceptions of the inhibitory effects of serum antiproteinases, naturally occurring inhibitors in serum, and the bacteriolytic effect of coliphages. The inhibiting effects are discussed in relation to the use of animal fodder containing lignosulphonic acids, and to the appearance of a selected microbial flora in sulphite spent liquor recipients.

Proteolytic enzymes and biological inhibitors. V. Serological relationship between bovine and swine trypsins and bovine -chymotrypsin

The serological relationship between bovine and swine trypsins, and bovine α-chymotrypsin has been studied with rabbit antisera at different stages in the immunization period. By using paper electrophoresis to distinguish between the naturally occurring inhibitors and the antienzymes in the γ-globulin fractions, combined with the casein precipitating inhibition test (electrophoretic CPI-test) it was found that at 18 days after immunization the antienzymes inhibited only the homologous enzymes. After an additional 12 and 24 days the anti- bovine trypsin also inhibited swine trypsin and α-chymotrypsin, and anti-swine trypsin inhibited bovine trypsin, while antia-chymotrypsin inhibited only the homologous enzyme. The enzyme inhibition in the heterologous systems was about 1/10 of that in the homologous systems. Similar results were obtained by applying the Kunitz test to isolated γ-globulins. The total trypsin inhibitory activity of the whole anti- bovine trypsin serum increased 50 % from the beginning to the end of the immunization period (tested on bovine trypsin).

Using the double diffusion technique, cross precipitation only occurred between anti-bovine trypsin and swine trypsin.

Acetyltrypsin (bovine) was affected by the 3 antisera in a way similar to native bovine trypsin.

The results are discussed in relation to other reports concerning the serological relationship of animal proteinases.

Identification of crude and purified bacterial proteinases by agar gel diffusion and agar gel electrophoretic procedures

The double diffusion technique, immunoelectrophoresis, the zymogram technique for proteinases and the casein precipitation inhibition test (GPI-test) were employed for identification of specific bacterial proteinases produced by Aeromonas liquefaciens, Aeromonas salmonicida and Pseudomonas aeruginosa. The precipitation lines observed with both homologous and heterologous proteinase-antiproteinase systems in the double diffusion technique and in immunoelectrophoresis, supported in certain respects previous findings regarding the Aeromonas proteinases, but the reactions were not sufficiently specific to give a confirmation of the real relationships between the proteinases. It is concluded that the double diffusion technique and Immunoelectrophoresis are less specific than the GPI-test for the identification of both crude, and purified, proteinase-antiproteinase systems. The zymograms, in combination with the immunoelectrophoretic patterns, could under certain conditions give useful information about the identity of lines representing the proteinase-antiproteinase precipitates in the double diffusion systems. The number of precipitation lines caused by the crude proteinase solutions in Immunoelectrophoresis decreased during storage of the crude antigens, and the solutions could finally behave like the solution of purified antigen.

It was shown that the GPI-test was at least 66 to 225 times more sensitive with respect to antigens, and two to three times more sensitive with respect to antisera than the double diffusion technique, for the three systems examined. This is of methodological importance, as high functional activity may be present in a proteinase solution although the structural conditions are unsuitable or the amount of enzyme protein is too small to allow the development of any precipitation lines in the double diffusion technique.