Abstract
In a successive series of papers published from our laboratory by Kasuya et al. (1956) and Hirai (1956), extensive studies on the chemical properties of the proteins obtained both from the culture filtrate and from the bacterial cells of the human tubercle bacilli have been reported.
The technique of the investigation used throughout these works has been the same in principle; namely, that every protein should be separated into its single peptides, and their identification and classification should in turn define the chemical characteristics of the original protein as a starting material.
With respect to the methodology, it can be said that such an approach is considered to play an important role also in exploring chemical knowledge on the protein of the different species of Mycobacteria. Thus, in major part, this paper deals with an application of the same methods to the study of the constituting peptide of Myco. avium. However, as a minor difference, it is to be mentioned that only the protein extracted from dried and defatted bacterial cells by dilute sulfuric acid was used as a starting material because the yield of protein from the culture filtrate was, generally, very small. Also, as to the technique of the determination of the N-terminal residue, not only the DNP-technique but also the PTC- (phenylthiocarbamyl) method were utilized when necessary.
