%0 Journal Article %A Tanamoto, Ken-ichi %A Iida, Takatoshi %A Haishima, Yuji %A Azumi, Satoko %T Endotoxic properties of lipid A from Comamonas testosteroni %D 2001 %J Microbiology, %V 147 %N 5 %P 1087-1094 %@ 1465-2080 %R https://doi.org/10.1099/00221287-147-5-1087 %K LAL, Limulus amoebocyte lysate %K PMA, phorbol myristate acetate %K endotoxin %K LPS %K lipopolysaccharide %K FCS, fetal calf serum %K biological activity of lipid A %K TNF-α, tumour necrosis factor alpha %I Microbiology Society, %X The lipid A from Comamonas testosteroni has been isolated and its complete chemical structure determined [Iida, T., Haishima, Y., Tanaka, A., Nishijima, K., Saito, S. & Tanamoto, K. (1996). Eur J Biochem 237, 468–475]. In this work, the relationship between its chemical structure and biological activity was studied. The lipid A was highly homogeneous chemically and was characterized by the relatively short chain length (C10) of the 3-hydroxy fatty acid components directly bound to the glucosamine disaccharide backbone by either amide or ester linkages. The lipid A exhibited endotoxic activity in all of the assay systems tested (mitogenicity in mouse spleen cells; induction of tumour necrosis factor alpha release from both mouse peritoneal macrophages and mouse macrophage-like cell line J774-1, as well as from the human monocytic cell line THP-1; induction of nitric oxide release from J774-1 cells; Limulus gelation activity and lethal toxicity in galactosamine-sensitized mice) to the same extent as did ‘Salmonella minnesota’ lipid A or Escherichia coli LPS used as controls. The strong endotoxic activity of the C. testosteroni lipid A indicates that the composition of 3-hydroxydecanoic acid is not responsible for the low endotoxicity of the lipid A observed in members of the genus Rhodopseudomonas, as has previously been suggested. Furthermore, both the lack of a second acylation of the 3-hydroxy fatty acid attached at the 3′ position, and the substitution of the hydroxyl group of the 3-hydroxy fatty acid attached at position 2, do not affect the manifestation of endotoxic activity or species specificity. %U https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-147-5-1087