Chemical and Ultrastructural Differences in Endotoxic Glycolipids from Salmonella Minnesota Re Mutant Extracted with Various Solvent Systems

Abstract

Endotoxic glycolipids (ReGl) extracted from the whole cells (WC) and cell walls of heptose‐less Re mutant of Salmonella minnesota with hot phenol‐water (PW), phenol‐chloroform‐petroleum ether (PCP), and chloroform‐methanol (CM) were analyzed chemically and examined with an electron microscope. ReGl‐PW‐(WC) contained mannose and proteins as contaminants, ReGl‐PCP(WC) consisted of an excess amount of amino compound (cadaverine), and ReGl‐CM(WC) consisted of proteins and cadaverine, in addition to the ReGl constituents. The ultrastructure of ReGl‐PW(WC) resembled onions when stained with uranyl formate, and was spherical when stained with uranyl acetate, sodium phosphotungstate and ammonium molybdate, whereas those of ReGl‐PCP(WC) and ReGl‐CM(WC) were shaped like ribbons. However, the shadowed ultrastructures of ReGl‐PCP(WC) and ReGl‐CM(WC) showed small pieces of flat and wide sheets, respectively. ReGl‐PCP(WC) re‐extracted by the PW method was found to be converted into the onion‐like structure which was similar to that of ReGl‐PW(WC), while an intermediate form (fingerprint‐like) was observed after re‐extraction of ReGl‐PW(WC) with PCP. It was strongly suggested that the ultrastructural arrangement of ReGl was dependent on the solvent systems used for extraction.

Chemical and Ultrastructural Comparison of Endotoxins Extracted from Salmonella minnesota Wild Type and R Mutants

“…1, d, f, and h) regardless of the difference in strains. The observations indicated above were the same as the morphology of ReGl described previously (1,2). The wild type LPS extracted with PW showed a filamentous structure (data not shown).…”

“…In this paper, we report that the composition and ultrastructures of R mutants RGl were different depending on the solvent systems used for extraction. This result supported the results for endotoxin from Re mutant described previously (2). MATERIALS AND METHODS…”

“…The compound (RGlcN=0.5), which is a major component, corresponded to cadaverine (1, 5-diaminopentane) on the basis of the pattern of proton magnetic resonance, comparison of the migration rate with commercial cadaverine by paper chromatography, and chemical analysis as described previously (2). Compound (RGlcN=0.2) was identical to phosphoethanol amine.…”

“…In a previous paper, we reported that the chemical composition and ultra structures of the ReGl from S. minnesota Re mutant cells differed according to the methods used for extraction (2).…”

Utilization of Proteinase K‐Treated Cells as Lipopolysaccharide Antigens for the Serodiagnosis of Helicobacter pylori Infections

“…Cultivation and purification of these bacteria were described previously (23). Small amounts of LPSs from the H. pylori strains described above were extracted and purified by a previous method (1). LPSs from Bordetella pertussis TOHAMA and B. parapertussis 21815 (2), Proteus vulgaris OX2, OX19 and P mirabilis OXK (17), Campylobacter fetus GIFU (4), and Salmonella minnesota Re mutant (1) were also extracted and purified according to previous methods.…”