| Autor: |
Mashimo, Jun‐ichi, Tanaka, Chiharu, Arata, Satoru, Akiyama, Yuri, Hata, Seiichi, Hirayama, Tohru, Egawa, Kiyoshi, Kasai, Nobuhiko |
| Zdroj: |
Microbiology and Immunology; July 1988, Vol. 32 Issue: 7 p653-666, 14p |
| Abstrakt: |
The relation of chemical structure to local Shwartzman activity of lipid A preparations purified by thin‐layer chromatography from five bacterial strains was examined. Two lipid A fractions from E. coliF515—Ec‐A2 and Ec‐A3—exhibited strong activity, similar to that of previous synthetic E. coli‐type lipid A (compound 506 or LA‐15‐PP). The Ec‐A3 fraction contained a component that appeared to be structurally identical to compound 506, and the main component of Ec‐A2 fraction was structurally similar to compound 506 except that it carried a 3‐hydroxytetradecanoyl group at the C‐3′ position of the backbone in place of a 3‐tetradecanoyl‐oxytetradecanoyl group. Free lipid A (12 C) and purified lipid A fractions, Ec‐A2 (12 C) and Ec‐A3 (12 C), respectively, obtained from bacteria grown at 12 C, exhibited activity comparable to Ec‐A2 or Ec‐A3. In these preparations, a large part of the 3‐dodecanoyloxytetradecanoyl group might be replaced by 3‐hexadecenoyloxytetradecanoyl group. Salmonella minnesotaR595 free lipid A also contained at least two active lipid A components as seen in E. colilipid A, but the third component corresponding to the synthetic Salmonella‐type lipid A (compound 516 or LA‐16‐PP) exhibited low activity. A lipid A fraction, Cv‐A4 from Chromobacterium violaceumIFO 12614, which was proposed to have two acyloxyacyl groups at the C‐2 and C‐2′ positions with other acyl groups, exhibited weaker activity than the free lipid A or LPS. The purified lipid A fractions from Pseudomonas diminutaJCM 2788 and Pseudomonas vesicularisJCM 1477 contained an unusual backbone with 2,3‐diamino‐2,3‐dideoxy‐d‐glucose disaccharide phosphomonoester, and these lipid A (Pd‐A3 and Pv‐A3) exhibited strong activity comparable to the E. colilipid A. Thus, the present results show that the local Shwartzman reaction can be expressed by partly different lipid A structures in both hydrophilic backbone and fatty acyl residues; when they have the same backbone the potency varies markedly depending on the structure of the acyl residues. |
| Databáze: |
Supplemental Index |
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