PB1-F2 protein is a factor of virulence of influenza A viruses which increases the mortality and morbidity associated with infection. Most seasonal H1N1 Influenza A viruses express nowadays a truncated version of PB1-F2. Here we show that truncation of PB1-F2 modified supramolecular organization of the protein in a membrane-mimicking environment. In addition, full-length PB1-F2(1-90) and C-term...

Based on literary data, conditions necessary for membrane fusion are discussed. It is proposed that fusion mechanisms should be classified according to the primary act involving a change in the membrane structure. Two principal fusion mechanisms are identified: the stalk mechanism, starting with the appearance of a stalk between approaching membranes, and the adhesion mechanism which involves b...

It has been generally assumed that the substances responsible for biological false positive (BFP) seroreactions for syphilis are antibodies of the same kind as the syphilitic anti-lipoidal antibodies. However, the available evidence for this view is meagre and mainly circumstantial. It has been observed that in the VDRL test substitution of the cardiolipin in the antigen by certain surface-acti...

Lipids not only form the backbone of biological membranes, but also serve as the source of numerous regulatory and signaling molecules. Understanding the role of lipids in the physiology of eukaryotic cell will help to identify mechanisms behind lipid-related human diseases. This minireview concentrates on two examples of human diseases associated with phospholipid remodeling and transport. The...

Cardiolipin antigens, used in the sero-diagnosis of syphilis, are mixtures of the phospholipids, cardiolipin, and purified natural lecithin (beefheart or egg), and usually also contain cholesterol. In 1949 Baer and Kates (1949, 1950) succeeded in the synthesis of L-ac-dimyristoyl lecithin and in the following years other types of synthetic lecithin were produced, including a D-oc-dimyristoyl le...

The Xuorescent dye 10-N-nonyl acridine orange (NAO) is extensively used for location and quantitative assays of cardiolipin in living cells on the assumption of its high speciWcity for cardiolipin; however, the limits and the mechanism of this speciWcity are not clear. Moreover, whether factors such as the membrane potential in mitochondria may limit the consistency of the results obtained by t...

Phosphatidylglycerol is found in almost all bacterial types. For example, Escherichia coli, a widely studied organism, has up to 20% of phosphatidylglycerol in its membranes (phosphatidylethanolamine makes up much of the rest with a little cardiolipin). In many bacteria, the diacyl form of the lipid predominates, but in others the alkylacyland alkenylacyl forms are more abundant. Phosphatidylgl...

A comparison of cardiolipin and a modified Treponema pallidum haemagglutination assay (TPHA) method over a four year period confirmed the superior sensitivity and specificity of TPHA. In 86,495 new donor sera 19 (0.02%) confirmed positive results were detected by TPHA, 10 of which did not react by the cardiolipin test. In 150,789 antenatal samples 49 confirmed positive results were found by TPH...

The presence of anti-cardiolipin antibodies (aCL) in women is an established risk factor for fetal loss, but these autoantibodies had not previously been investigated in the male partners of recurrent aborters. The prevalence of aCL in 144 male partners of couples with a history of recurrent miscarriage was 4.2%, which compares with 2.8% for 177 female partners of such couples, 5.9% of 254 bloo...

CD22 is a B cell-specific transmembrane glycoprotein that acts to dampen signals generated through the B cell antigen receptor (BCR): B cells from CD22-deficient mice give increased Ca2+ fluxes on BCR ligation. Here we show that this B cell hyperresponsiveness correlates with the development of autoantibodies. After the age of eight months, CD22-deficient mice developed high titers of serum IgG...