Granuloma-forming activity and antitumor activity of newly isolated mycoloyl glycolipid from Rhodococcus terrae 70012 (Rt. GM-2).
A newly isolated mycoloyl glycolipid (Rt. GM-2) from Rhodococcus terrae 70012 was identified and the granulomagenic and antitumor activities were studied as compared with trehalose-6,6'-dimycolate (cord factor) also from R. terrae (Rt. TDM). The alkaline hydrolysis products of Rt. GM-2 contained trehalose, methyl-alpha-mycolate and a less-polar ester than the usual methyl-alpha-mycolate, possibly beta-keto mycolate (1:1:1, by mol. ratios). On the other hand, analysis of alditol acetate obtained after the mild permethylation, NaBH4 reduction, and acetylation showed the occurrence of 2,3,4-tri-O-methyl-6-O-acetylglucitol. Therefore, the original glycolipid (Rt. GM-2) was identified tentatively as 6-O-alpha-mycoloyl 6'-O-beta-ketomycoloyl trehalose. Intravenous injection of Rt. GM-2 in the form of water-in-oil-in-water emulsion caused prominent granulomas in lungs and spleen of ICR and BALB/c mice. The granulomagenic effects were as strong as those caused by Rt. TDM. The lung and spleen weights reached peaks one week after an injection of Rt. GM-2 in mice and then gradually decreased. Multiple intravenous injections of Rt. GM-2 and Rt. TDM showed antitumor activity against subcutaneously implanted Sarcoma-180, and caused prominent granulomatous changes and growth suppression of mice.
Natsuhara
Y
Y
Department of Bacteriology, Osaka City University Medical School.
Yoshinaga
J
J
Shogaki
T
T
Sumi-Nishikawa
Y
Y
Kurano
S
S
Kato
Y
Y
Kaneda
K
K
Oka
S
S
Yano
I
I
D000276:Adjuvants, Immunologic; D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D003311:Cord Factors / Q000627:therapeutic use; D006017:Glycolipids / Q000302:isolation & purification / Q000627:therapeutic use*; D006099:Granuloma / Q000276:immunology*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009171:Mycolic Acids / Q000302:isolation & purification / Q000627:therapeutic use*; D009928:Organ Specificity; D012240:Rhodococcus / Q000378:metabolism*; D012509:Sarcoma / Q000188:drug therapy*; D014407:Tumor Cells, Cultured
D000276:Adjuvants, Immunologic; D000970:Antineoplastic Agents; D003311:Cord Factors; D006017:Glycolipids; D009171:Mycolic Acids