Absence of lipopolysaccharide in the Lyme disease spirochete, Borrelia burgdorferi

Abstract

We were unable to deMonstrate the presence of the classic enterobacterium-type lipopolysaccharide in the cells of the Lyme disease spirochete, Borrelia burgdorferi B31. This finding was primarily based on chemical analysis and the absence of free lipid A upon mild acid hydrolysis of the appropriate cell extracts. These re4ults do not preclude the possible existence of an unusual lipopolysaccharide-like compound(s) in B. burgdorferi. Beck et al. (4) recently reported the presence of lipopolysaccharide (LPS) irq the Lyme disease spirochete (Borrelia burgdorferi). We wanted to confirm their results and then examine the nature of the lipid A moiety of LPS from this source. We extracted the cells of B. burgdorferi B31 by two well-known methods used in the isolation of LPS from gram-negative bacteria. The appropriate fractions obtained by these two methods were hydrolyzed under mild acid conditions and examined by thin-layer chromatography (TLC) for the presence of free lipid A. Chemical analyses for the presence of 2-keto-3-deoxyoctonate, glucosamine, and hydroxy fatty acids were performed on the extracts. We found no evidence for the presence of lipid A in any of the fractions tested. Thus, we must conclude that the classic LPS associated with gram-negative bacteria is absent in cells of B. burgdorferi.Cells of B. burgdorferi B31 (ATCC 35210) were grown in BSK II medium (1), washed three times with 50 mM Tris (pH 7.4)-150 mM NaCI-5 mM MgCI2 (2), and lyophilized. In one experiment, the extraction method of Galanos et al. (7) with modifications was used (12,14). The results of this extraction are summarized in Table 1. Almost all of the extractable material was found in the 90% aqueous ethanol fraction, whereas very little material appeared in the phenol-waterchloroform-petroleum ether fraction, which should contain the rough-type LPS (R-LPS). This latter fraction was hydrolyzed in 0.1 N HCI as previously described for the preparation of monophosphoryl lipid A (14), and 30 ,ug of the organic extract was analyzed by TLC for the presence of lipid A (12,14). A mixture of hexa-, penta-, and tetraacyl monopliosphoryl lipid A (from LPS of Salmonella typhimurium) was used as a chromatographic standard (13). There was no evidence of the presence of free lipid A in this sample, indicating the absence of R-LPS in the original extract (phenol-water-chloroform-petroleum ether).Previous studies of lipids X and Y (monosaccharide precursors of LPS) showed that much of X and Y was extracted into the aqueous ethanol fraction (15,16). Thus, it is conceivable that the 113.2 mg of the 90% ethanol extract (Table 1) might contain the R-LPS. This material was initially fractionated by solvent precipitation to yield 79.9 mg of an acetone-insoluble glycolipid-phospholipid fraction. This * Corresponding author. fraction was further purified by preparative TLC on Silica Gel G (Merck & Co., Inc.) by a solvent system of chloroform-methanol-water (65:25:4). Five major fractions (designated A to E) were obtained. Each of these fractions was acid hy...

Borrelia burgdorferipotently activates bone marrow-derived conventional dendritic cells for production of IL-23 required for IL-17 release by T cells

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Functional analysis of a lipid galactosyltransferase synthesizing the major envelope lipid in the Lyme disease spirocheteBorrelia burgdorferi

“…Borrelia spp. are regarded as Gram-negative bacteria; however, borrelial cell envelope composition differs from other Gram-negative bacteria, as it lacks a typical lipopolysaccharide (Takayama et al, 1987) and phosphatidylethanolamine (Belisle et al, 1994). However, the presence of glycolipid antigens other than lipopolysaccharide has been detected (Cinco et al, 1991;Eiffert et al, 1991;Wheeler et al, 1993;Belisle et al, 1994;Honarvar et al, 1994).…”

Non‐heritable change of a spirochaete's phenotype by decoration of the cell surface with exogenous lipoproteins

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