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20 bacterial strains (corresponding to 16 species) were screened for ornithine lipids. Only two species (Thiobacillus A2 and Achromobacter sp.) turned out to contain ornithine lipids (2.71 mmol/100 g and 0.38 mmol/100 g bacterial dry weight, respectively). In both ornithine lipids, a 3-hydroxy fatty acid was amide-linked to the alpha-amino group of ornithine, a normal fatty acid was ester-linked to the 3-hydroxy group of the former. The predominant fatty acids were 18:1(11) and 3-hydroxy-20:1(13) in Thiobacillus A2, 16:0 and 3-hydroxy-18:1(11) in Achromobacter sp. All monounsaturated fatty acids (with one exception) belonged to the (n-7) family. 11, 12-Epoxy octadecanoic acid was identified among the ester-linked fatty acids of Thiobacillus A2. Phosphatidylcholine was the principal phospholipid in both bacterial species.

Total lipids extracted from J-positive cattle serum, erythrocytes or spleen exhibit J blood-group activity. The J subsance is concentrated in a lipid fraction obtained by column chromatography. Following mild alkaline hydrolysis or reduction with complex hydrides (LiAlH4, LiBH4), the J activity remains detectable in this lipid fraction even though all acyl ester groups have been destroyed as revealed by ester group determination. This disagrees with the suggestion that fatty acyl esters are essential for J activity. This was confirmed by experiments with a water-soluble J-active product prepared by ozone treatment of glycosphingolipids from bovine spleen. The results of these experiments are in favour of a glycosphingolipid containing anunusually lang oligosaccharide chain. Furthermore, it appears that the terminal moiety of the J determinant is not necessarily an N-acetyl galactosamine unit as suggested previously.

The porcine A blood group substance is found in the serum as a lipid and, additionally, in certain animals, as a glycoprotein. Swine lymphocyte antigens (SLA) occur in the serum only as glycoproteins. Heat treatment of the solid residue obtained by lipid extraction yielded a water-soluble fraction with low protein content, high A activity, but no SLA activity. Poly(glycosyl)ceramides with SLA activity do not occur in the serum; poly(glycosyl)ceramides with A activity cannot be excluded. Desialylation of protein fractions has no effect on A and SLA activity. Both A and SLA activities of protein fractions are stable to mild alkaline hydrolysis thus indicating N-glycosidic carbohydrate-peptide linkages.

Two glycosphingolipids with J blood group activity were found in J-positive bovine spleen. They were tentatively identified as ceramide deca- and dodecahexosides containing galactose, glucose, N-acetylgalactosamine and N-acetylglucosamine in a molar ratio of 5:3:1:1 and 6:3:2:1, respectively. Fucose was not present. Ceramide decahexosides without J activity were also found in J-negative bovine spleen. The principal component fatty acids of the J-active glycosphingolipids were saturated even-numbered long-chain acids with 16 to 24 C atoms. Their principal long-chain bases were sphingosine and dihydrosphingosine with smaller amounts of phytosphingosine. Both J-active glycosphingolipids were readily water-soluble and showed strong activity in the bovine J and in the porcine A blood group system. They exhibited no cross-reactivity in the human A system. However, a J-negative glycosphingolipid fraction - also from J-negative spleen - with shorter carbohydrate chain-length showed strong activity in the human A system.

Lipids and protein-containing nonlipids of pig erythrocytes, serum and several organs were tested for A blood group activity. Both lipids and nonlipids of brain, myocardium, skeletal muscle and adipose tissue show no A activity. The way of distribution of A activity on lipids and nonlipids of other tissues and serum differs among individual pigs. With respect to the acquisition of A activity of erythrocytes in a postnatal period, it seems likely that the lipidic A substance Tor part of it containing the A determinant) is transferred from plasma to the erythrocyte membrane.

Ghosts of J-positive bovine erythrocytes were frozen overnight, thawed the next day, washed with ion-free water, and then extracted with a water-n-pentanol mixture. After centrifugation, the aqueous phase contained a great deal of the membrane proteins and lipids in a soluble form along with the J blood-group activity. After preparative ultracentrifugation, about 2/3 of the J activity were recovered in the high-density lipoprotein fraction, while the low-density lipoprotein fraction contained 1/3 J activity. This result is consistent with out finding that on treatment of the stroma lipoproteins with dextran sulphate, about 2/3 of J activity were recovered in the supernatant, 1/3 in the precipitate. These fractions obtained by dextran sulphate treatment were characterized by protein and lipid assay.

The isolation and characterization of an ornithine-containing lipid from various strains of Paracoccus denitrificans (grown heteretrophically and autotrophically) is reported. The structure of this aminolipid was found to be H2N--CH2--(CH2)2--CH[NH--CO--CH2--CH(O--CO--R1)--R2]--CO2H, where R1 predominantly represents the residue of octadec-11-enoic acid, R2 the residue of a 3-hydroxyeicos-13-enoic acid. In addition, the major phospholipids (phosphatidylcholine, phosphatidylethanolamine, phosphatidylglycerol) were isolated and characterized.

The isoprenoid quinone content and composition of several strains of the following hydrogen oxidizing bacteria were studied: Xanthobacter autotrophics, Xanthobacter flavus, Paracoccus denitrificans, Pseudomonas pseudoflava, P. carboxydovorans, P. carboxydo-hydrogena. All strains studied contained ubiquinone (UQ) in concentrations between 0.7 and 2.8 μmol/g bacterial dry weight. No menaquinones were found. UQ of all strains (except one) contained side chain lengths of 10isoprenoid units (UQ-10), two strains contained in addition UQ-8. UQ-9 was found in Pseudomonas carboxydohydrogena only., (Copyright © 1983 Gustav Fischer Verlag, Stuttgart/New York. Published by Elsevier GmbH.. All rights reserved.)

THe bovine J determinant is transferred from a bovine serum nonlipid fraction to a human erythrocyte membrane lipid by an incubation procedure. The transferred J determinant is detected in the total lipids extracted from transformed human erythrocytes by an inhibition test in the bovine J system. It is also detected by cross-reacting human anti-A sera after treatment of human cells with papain prior or subsequent to transformation.

15 strains of hydrogen-oxidizing bacteria were grown heterotrophically, harvested during the stationary phase of growth, and analyzed for their principal phospholipids. All strains - with the exception of Corynebacterium autotrophicum strain SA 32 and Pseudomonas pseudoflava - contained phosphatidylcholine as a major constituent. It is concluded that the presence of phosphatidylcholine is neither characteristic of a peculiar bacterial genus or family, nor is it absolutely correlated to the ability to oxidize hydrogen. The phosphatidylcholines of all strains contain C19 cyclopropane acid which is, in some strains, predominantly located at C-2 position of the glycerol moiety.

1. Treatment of J-positive (Jcs) bovine erythrocytes with periodate (0.25 mmol/l final concentration, 1 hour, room temperature) has no effect on the J activity. Higher periodate concentrations cause spontaneous haemolyses. 2. Treatment of the lipids extracted from (and containing all J activity of) Jcs erythrocytes with periodate leads to a decrease of J activity even with lower periodate concentrations. 3. Treatment of the stroma prepared from Jcs erythrocytes with periodate demonstrated the relative stability of the J antigen up to 0.25 mmol/l periodate. At the same time the sialic acid concentration of stroma is reduced to about 13% of the initial concentration. 4. Desialylation of Jcs erythrocytes or Jcs stroma with sialidase does not affect the J activity thus confirming previous findings. On the other hand, the J activity of desialylated Jcs stroma is much more susceptible to periodate. 5. It is concluded that membrane-bound sialic acid shields the membrane-bound J antigen from being attacked by periodate.

The bovine J blood group substance exists as a glycosphingolipid (ceramide decahexoside as well as ceramide dodecahexoside) and as a glycoprotein. The lipidic form occurs in erythrocyte membranes, both forms are found in serum. The lipidic J substances were isolated from erythrocytes and from serum, and identified by thin-layer chromatography with lipidic J substances isolated from spleen. The glycoprotein nature of the non-lipidic J of serum was evident by pronase-catalysed hydrolysis yielding J-active glycopeptides of lower molecular weights. The lipidic J was completely extracted from lyophilized stroma with chloroform/methanol. From lyophilized serum, however, it was completely extracted only in the presence of water, indicating different binding partners in serum and in erythrocyte membranes. The J lipid was incorporated as intact molecule into the erythrocyte membrane by a simple incubation technique. The incorporation was inhibited by various glycerophospholipids (called blockers). The J glycoprotein could not be transferred to the erythrocyte membrane. Three methods are described which are suitable for the preparation of a blocker-free fraction enriched with J lipids from J-positive serum.

There is a diversity of carriers of the J blood-group activity of bovine serum. The qualitative and quantitative distribution of the J activity on different carriers was studied, using various fractionation procedures. Approximately one third of J activity was found in the total lipids extracted from serum, two thirds in the lipid-free residue precipitated by lipid extraction. One third of the lipid J substance was found to be bound to the very low density lipoprotein, two thirds to the low density lipoprotein, while the high density lipoprotein was completely free of J activity. All non-lipidic J substance was present in the lipid-free protein. There was no J activity in the low molecular weight mucoproteins of serum and in the apoproteins of the lipoprotein fractions. The lipoprotein fractions were prepared by ultracentrifugation at different solvent densities. The lipoprotein fractions were characterized by chemical analyses and physical properties. The lower total cholesterol concentration of bovine serum, as compared to human serum, is reflected in a lower concentration of low density lipoprotein. The results obtained by ultracentrifugation coincide with the results obtained by precipitation of "beta-lipoproteins" with dextran sulfate and calcium chloride and with results obtained by gel filtration of bovine serum. The "beta-lipoprotein" fraction contains lipoproteins of very low and low density, and probably chylomicrons and a variety of other proteins, however no high density lipoprotein.

The A blood-group activity of pig serum is bound to a lipid, in some cases also to a nonlipid fraction. The major lipidic A activity (roughly 50%) is carried with the HDL class, while the VLDL and LDL classes contain roughly 25% each.

A nystatin-resistant mutant of Rhodotorula gracilis was obtained by treatment of the wild strain cells with N-methyl-N-nitro-N-nitrosoguanidine and selected on agar plates containing 150 micrograms nystatin/ml. Three important transport functions of the plasma membrane of mutant cells: the accumulation of monosaccharides, the generation and maintenance of the pH-gradient and of the membrane potential, as well as the cell respiration were insensitive to at least 10(-5) M nystatin. This concentration of nystatin inhibited completely all these processes in wild strain cells. Analysis of cellular sterols revealed a defect of ergosterol biosynthesis in the mutant, which was localized at the last oxidative step between 5,6-dihydroergosterol and ergosterol.

During autopsies of 34 individuals, 110 specimens were taken from femoral arteries and examined by microscopy and lipid chemical analyses. Five types of lesions were differentiated: 1. normal intima, 2. diffuse intimal hyperplasia, 3. fatty streaks, 4. fibrous plaques, 5. atheromatous lesions. Since studies on femoral arteries have not been performed so far, our results were compared with known results from aortas and coronary arteries. However, no essential differences were found by comparing morphologic results and lipid compositions. Esterified and free cholesterol increased approximately 30-fold, phospholipids approximately 6.5-fold, with progressing atherosclerosis. The intima of a 40-year-old alcoholic was found to have an extremely low level of cholesterol esters, while the other findings were not changed.

A procedure for the quantative determination of glycosphingolipids is described, involving extraction of total lipids, fractionation on a column, acid cleavage and photometry of a complex formed between sphingosine and methyl orange. The level of glycosphingolipid sphigosine of erythrocyte membranes of a variety of mammals ranges from 59.1 (rat) to 410.1 (pig) nmol/ml packed cells.