Cells of Vibrio cholerae, strain Inaba, actively growing in a hypertonic sucrose-broth were exposed to penicillin (5-1, 000u/ml), glycine (0.5-3%) or lithium chloride (1.0-2.5%). Most cells were converted to osmotically fragile spheroplasts within 1 to 3 hours. The process of the spheroplast formation in V. cholerae as followed by the electron microscope was similar to that observed in the other Gram-negative bacteria. Penicillin-induced spheroplasts were generally larger than those arising by use of other agents.
The spheroplasts retained their single flagellum and displayed active movements for a long period. Both the motility and viability of glycine- and LiClinduced spheroplasts were preserved considerably longer than those from penicillin.
When aerated cultures were placed under semianaerobic conditions by stopping the aeration, a few cells were spontaneously converted to spheroidal forms.

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1. 8-Azaguanine delayed the growth of Mycobacterium avium Jucho and Escherichia coli. This action was influenced by the size of the inoculum. It was never bactericidal.
2. The combined action of streptomycin with 8-azaguanine inhibited the growth of M. avium synergistically.
3. The combination of streptomycin with 8-azaguanine inhibited very effectively the in vitro emergence of streptomycin resistance in M. avium, but it did not inhibit the emergence of isoniazid resistance in the same organism.
4. 8-Azaguanine seemed sometimes as if to produce an increase in mutation frequency in M. avium. However, this effect remained insignificant.
5. The pre-treatment of M. avium, as well as of E. coli with 8-azaguanine (60 μg/ml, 3 hours under shaking) caused a marked increase in streptomycin susceptibility, but it caused no modification of mitomycin susceptibility. The possibility is that this modficaton of streptomycn susceptibility is contributed by the combined effect of streptomycin with 8-azaguanine.

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An analysis of the cell hydrolysate of pleuropneumonia-like organisms (PPLO) shows that the PPLO lack specific components of the mucocomplex which bears the rigidity of cell wall. The PPLO contain a relatively specific component, glucosamine, in about 1per cent or more of the dry weight of cells. About two-thirds of this substance is present in the acid precipitate. The role of this substance in PPLO has been discussed in relation to. the results obtained by other investigators on PPLO and L-form and to the action of some inhibitors of cell wall synthesis.

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