STUDIES ON THE METABOLISM OF THE TUBERCLE BACILLUS WITH THE USE OF RADIOACTIVE SUBSTRATES IN THE PRESENCE AND ABSENCE OF STREPTOMYCIN
1954 年 41 巻 2 号 p. 167-181
詳細
1954 年 41 巻 2 号 p. 167-181
The incorporation of radioactivities from CH3C14OOH and C14 uniformly labeled glucose, in the absence and presence of streptomycin, by Mycobacterium tuberculosis H37RV, streptomycin sensitive and strepto-mycin resistant (H37RVSR) variants, was studied. A study was also made on the uptake of radioactivity from NaHC14O3 by the sensitive organism.
The incorporation of radioactivity from bicarbonate was uniformly low in all the amino acids. From acetate the highest specific activities were in glutamic acid and in proline, while in the glucose studies phenylalanine and tyrosine had the highest specific activities. The uptake of radioactivity from acetate into the amino acids was somewhat greater in the resistant strain than in the sensitive. Ninhydrin reactions of aspartic acid and leucine removed practically all the radioactivities incorporated from acetate, while in glutamic acid and praline, the reactions left more than half of the activities in the residual molecules.
Streptomycin caused a decrease in the uptake of radioactivity from acetate into most of the amino acids in the sensitive strain. One notable exception was glutamic acid which does not appear to be affected. In the resistant strain some decrease was also noted in uptake of radioactivity from acetate into the amino acids including glutamic acid. Incorporation of radioactivity from glucose into the amino acids in the sensitive strain was definitely decreased to a level no more than that obtained with bicarbonate by the antibiotic, while incorporation into the resistant strain was apparently unaffected.
The possible explanations and significance of the results observed are discussed.
I wish to thank Dr. C. Richard Smith for his patient guidance and advice. I am also indebted to Mr. Elmer Rice for his tireless efforts in keeping the various instruments in working order, and to Mr. Cornelius Y. Chiamori and Mrs. Annie Fry for their skillful assistance on innumerable occasions.
