Cells of Serratia marcescens, whether pigmented or unpigmented, contained 10–11% of methanol–chloroform extractable lipids (dry weight basis) and < 1% of bound lipids. The extractable lipids contained 34–43% phosphatides, 3–11% unsaponifiable material, and 2–5% free fatty acid. The phosphatides contained high proportions of phosphatidyl ethanolamine and smaller amounts of phosphatidyl serine, polyglycerol phosphatides, phosphatidyl glycerol, and an unidentified ninhydrin-positive phosphatide probably associated with ornithine and other amino acids found in the lipid hydrolyzate.The fatty acids were found to consist largely of palmitic, C17- and C19-cyclopropane and C16- and C18-monoenoic acids. The proportions of monoenoic and cyclopropane acids were found to vary greatly with the age of the cultures; in the early stages of growth, regardless of pigmentation, low amounts of cyclopropane acids and high amounts of monoenoic acid were present, the latter being converted almost completely to cyclopropane acids during the active growth phase.The lipids associated with extracellular lipopolysaccharide material were similar in composition to the cellular lipids.

Lipopolysaccharides have been isolated from seven species of Gram-negative bacteria and their acid hydrolysates have been examined by gas–liquid partition chromatography for the presence of aldoheptoses. All contained D-glycero-D-manno-heptose in addition to the well-known aldoheptose component L-glycero-D-manno-heptose. The relative proportions of these two aldoheptoses varied widely between species of bacteria and to a lesser extent between members of the same species. Both aldoheptoses were isolated from a lipopolysaccharide prepared from E. coli cells and were positively identified by physical and chemical methods. The chromatographic method used for determining the aldoheptoses also provided means for simultaneous detection of 3-deoxy-D-manno-octulosonic acid (KDO).

Lipopolysaccharides (LPS) prepared from N. catarrhalis cells were separated into a chloroform-soluble fraction (26%) and a chloroform-insoluble fraction (74%). Both LPS fractions contained D-glucose, D-galactose, D-glucosamine, galactosamine, lipid A, ethanolamine, fatty acids, acetyl, phosphate, and protein in approximately equal proportions. The lipid A moieties prepared from the two LPS fractions were also similar in composition to each other. The fatty acids and galactosamine of the LPS fractions were recovered quantitatively in their lipid A fractions. The major fatty acid component was β-hydroxylauric acid in contrast with β-hydroxymyristic acid, which is the major fatty acid component of the lipid A of N. perflava and other Gram-negative bacteria. The lipid A of N. catarrhalis also contained a considerable amount of D-glucose and D-galactose, which are not normal constituents of lipid A fractions. The presence of amino acids (ca. 2%) in all fractions suggested that proteins were an integral part of the LPS molecules. The absence of heptose and 3-deoxyoctulosonic acid (KDO) from the N. catarrhalis LPS shows that it lacks a lipopolysaccharide "core" structure similar to that present in the LPS of N. perflava; the polysaccharide part of the LPS molecule is also compositionally different from that of N. perflava. These differences may provide additional evidence to that already accumulated from other sources that N. catarrhalis is taxonomically a "false neisseria".

The chemical composition and serological reactions of lipopolysaccharides from serogroups A, B, X, and Y Neisseria meningitidis. Can. J. Biochem. 51, 1347Biochem. 51, -1354Biochem. 51, ( 1973.Analyses of the cell wall lipopolysaccharides prepared from Neisseria meningitidis serogroups A, B, X, and Y, indicated that they all contained glucose, galactose, glucosamine, heptose, lipid A, ethanolamine, fatty acids, phosphate, and protein. &me minor compositional differences in the sugar components did occur in that sialic acid (6-7%) was found only in serogroups B and Y, and galactosamine (2-3% ) in serogroups B and X. The individual fatty acid and amino acid compnents in the four wrogroups were also qualitatively similar. The Neisseria lipopalysaccharides studied have the same components as the core structure of the Enterobacterioceae but appear to lack the characteristic components of their 0-antigen side chains. Serological studies indicated that the lipopolysaccharides were homogeneous and were for the main part group specific in nature, despite their compositional similarity. On the basis of compositional differences alone it is not possible to account for the group specificity that they exhibit. JENNINGS, H. J., HAWES, C. El., ADAMS, G. A., et KENNY, C. P. The chemical composition and serologicaI reactions of lipopolysaccharides from serogroups A, B, X, and Y Neisseria meningitidis. Can. J . Biochem. 51, 1347-1354 (1973).k s analyses de lipopolysaecharides de la paroi cellulaire extraits des groups skriques A, B, X et Y de Nebseria meningitidis indiquent qu9ils contiennent tous les eonstituants suivants: glucose, .galactose, glucosamine, heptose, lipide A, tthanolamine, acides gras, phosphate et protkine. Quelques difftrences mineures peuvent se produire dans la composition glucidique: l'acide sialique ( 6 7 % ) n'est prksent que dans les groupes skriques B et Y et la galactosamine (2-3 % ) que dans les groups skriques B et X. Les acides gras et les acides amints individuels des quatre groups shriques sont qualitativement semblables. Chez Neisseria les lipopolysaccharides Ctudiks possuent les m h e s constituants que la structure principak des Enterobscterioceae mais les constituants caractkristiques des chaines latkrales de leur antighe 0 y sont absents. Las ktudes skrologiques montrent que les lipopolysaccharides sont homoghnes et que la plupart jouissent d'une sp6cificitk de groupe naturelle en cltpit des ressemblances de composition. Si on se base sur les seules difftrences de composition, il est impossible d'expliquer wtte sficificitk de groupe qu'ils exhibent.pracluit par le journal]

A B S T R A C T A neutral extracellular glucan ([a]nZ3 +18g0) was produced i n 127, yield b y Pullularia pullulans (de Bary)The yeast-like fungus Pullularia pullulans produces a mixture of glucose-containing extracellular polrsaccharides (I). I t has been shown (2, 3) that one of the polysaccharides formed by the fungus from glucose as the carbon source is a linear glucan ("pullulan") having [a], +192" and coinposed of approximately 300 a-D-glucopyranose units linked -(1 + 4) and (1 -+ 6) in the ratio 3:2. Bouveng et al. (4) have examined the polysaccharides produced by Pullularia pullulans from various sugar substrates, and have found that a sucrose medium yielded a linear glucan having [a], +190° and consisting of more than 250 units linked a ( l -+ 4) and a ( 1 -+ 6) in the ratio 2:l. A small amount (1-27,) of glucose remaining after periodate oxidation of the polysaccharide suggested that (1 -+ 3) linkages might be present, although this was not supported by methylation data. No evidence for the presence of (1 -+ 3) linkages ilT the polysaccharide produced from glucose was reported in earlier work (2, 3). The present publication reports the results obtained from partial acid hydrolysis and froin periodate oxidation of the glucan produced by Pullularia pullulans grown on glucose.The growth conditions of the organism and the method of recovery used for the preparation of the polj~saccharide in the present work favored isolation of the water-soluble glucan to the exclusion of the more insoluble jelly-like polysaccharide which adheres to the mycelium (1). The polysaccharide showed a single symmetrical peak on electrophoresis in borate and acetate buffers, gave no precipitate with Cetavlon, and showed no carboxyl absorption in its infrared spectrum. This evidence showed that the polysaccharide was homogeneous and contained no acid groups. Bouveng et al. (4) found that yields of polysaccharide were increased and that formation of uronic acid and other hexose units was diminished when the organism was grown on glucose rather than other sugar substrate (except for sucrose).Infrared spectroscopy of the polysaccharide showed strong absorption a t 850 cm-l,