Open AccessIn vitro deacylation of lipopolysaccharide of Salmonella minnesota by Acanthamoeba castellanii enzymes
Author(s) -
DROZANSKI Wincenty,
GALANOS Chris,
SCHLECHT Siegfried,
LÜDERITZ Otto
Publication year - 1986
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1986.tb09509.x
Subject(s) - lipid a , lipopolysaccharide , chemistry , biochemistry , heptose , enzyme , myristic acid , palmitic acid , glucosamine , mutant , biology , fatty acid , gene , endocrinology
Enzymatic deacylation of the lipopolysaccharide isolated from a Salmonella Rd mutant by a cell‐free preparation from Acanthamoeba castellanii has been studied. The degradation was found to be dependent on the presence of a surface‐active component (Triton X‐100) in the reaction mixture. The lipid A part of the lipopolysaccharide was the primary target of the enzymes, which cleaved with high efficiency the ester‐bound long‐chain non‐hydroxylated and 3‐hydroxylated acyl residues, i.e. lauric, myristic, palmitic and 3‐hydroxymyristic acid. The cell‐free preparation also exhibited amidase activity cleaving about 50% of the amide‐bound 3‐hydroxymyristic acid residues. In addition the extract proved to possess phosphatase activity liberating ester‐bound and glycosidically bound phosphate groups of lipid A. On the other hand, the glucosaminyl‐β1, 6‐glucosamine disaccharide was not degraded and remained bound to the oligosaccharide part (heptose/3‐deoxyoctulosonic acid) of the lipopolysaccharide.