[Patterns in the formation of proteolytic enzymes by different strains of C1. botulinum type F]. / Nekotorye zakonomernosti obrazovaniia proteoliticheskikh fermentov razlichnymi shtammami C1. botulinum tipa F

The authors studied regularities attending the accumulation of proteolytic enzyme and toxin by C1. botulinum, type F, strains in the medium. Strains No. 470, 200, 76, 55 proved to possess caseinolytic capacity, whereas strains Eklund and Craig were "nonproteolytic". C1. botulinum strain, type F, medium and growing conditions providing a high yield of proteolytic enzymes were selected. Some properties of proteolytic enzyme of strain No. 470 were studied.

[Contamination of fish by agents of botulism type F and differentiating it from type E]. / Obsemennost' ryby vozbuditeliami botulizma tipa F i differentsiatsiia ego s tipom E

A total of 1859 samples of fish and various sea animals were examined for contamination with causative agent of botulism. The cultural fluid of 4--5-day cultures of the samples was tested in the reaction of neutralization with the diagnostic antitoxic antibotulin sera. types A, B, C, E. The causative agents of botulism (types A--7,B--16, C--5, E--128) were revealed in 156 samples. The sera were diluted to the concentration of 1 IU/ml for differentiation of the toxins types B and F in the neutralization test. Of 128 samples which gave a positive reaction with the serum of type E, 75 were identified as type F. In connection with the aforesaid the authors recommended in all the cases of botulism of type E in man to carry out differential diagnosis between the causative agents of botulism of types E and F and, on the basis of these data, to solve the problem on the necessity of production of therapeutic antibotulin serum of type F.

[Deaminase activity of Cl. botulinum type A, B, E and F cultures]. / Dezaminaznaia aktivnost' kul'tur Cl. botulinum tipov A, B, E i F

The authors present the results of a comparative study of desaminase activity in the suspensions of resting cells and in ultrasonic desintegrates of cells of Cl. botulinum types A, B, E and F against a number of amino acids and their amides. It was shown that types A, B, E and F possessed active desamination enzymes; this process, however coursed with a different degree of intensity depending on the substrate. Common for all the 4 types was the presence of desamidase L-asparaginase and L-glutaminase, and also of the desamination enzymes of the aspartic and glutamic acids. Strains of type B had the greatest set of enzymes, and of type A--the least; bacteria of types E and F occupied an intermediate position. None of the types studied contained tryptophandesaminase. Some of desaminases are bound to subcellular structures.