[Use of the corycin test and of bacteriophage typing for genetic marking of corynebacteria with reference to C. diphtheriae of the gravis type].

Nontoxigenic C. diphtheria, fermenting starch, of convertible phage types ABCDFCH, ABCDFG, ABCDF, ABCD, ABD, ACDf, CDf, AF and A, and also strains of nonconvertible bacteriophage types I, H and K proved to be noncoricynogenic in the corycine test and weakly sensitive to bacteriocin of the No. 3463 test strain (a study was made of a total of 502 strains). Strains (383) isolated from 354 patients and carriers--starch-fermenting and toxigenic to the gravis type--were toxigenic were lysed by a combination of bacteriophages O, P, Q, R, S, T produced an active bacteriocine against the test strains No. 23 BC, and were insensitive to bacteriocine of the strain No. 3453. Strains of phage type G(g) were noncorycinogenic. Only one strain of phage type G, which produced corycine, active against the test strain No. 23 BC served as an exception. With the aid of phages A, B, C, D, F, G, H, I, K it was possible to separate 244 strains of the phage type G(g) into 3 phage types--bc, ABfGH and Abg. Strains of phage type ABfGH were noncorycinogenic; the only strain of phage type bG available produced bacteriocine.