ACTA AGRONOMICA TOMUS 27. (A MTA AGRÁRTUDOMÁNYI KÖZLEMÉNYEI, 1978)
1978 / 1-2. szám - S. FAZEKAS-I. ÓVÁRY-V. SZÉKESSY-HERMANN-E. TÁTRAI: Two variations of lipid in myosin. Anisotropy of lipid chelate and interaction complexes with Mg2+ and Ca2+ ions and basic amino acids
Acta Agronomica Academiae Scientiarum Hungaricae, Tomus 27 (1—2), pp. 1—15 (1978) TWO VARIATIONS OF LIPID IN MYOSIN. ANISOTROPY OF LIPID CHELATE AND INTERACTION COMPLEXES WITH Mg2h AND Ca2^ IONS AND BASIC AMINO ACIDS By S. FAZEKAS, I. ÓVÁRY, V. SZÉKESSY-HERMANN, Б. TÁTRAI 2ND INSTITUTE OF CHEMISTRY AND BIOCHEMISTRY, CLINIC OF PSYCHIATRY, SEMMELWEIS MEDICAL UNIVERSITY OF BUDAPEST, TÉTÉNYI STREET HOSPITAL, BUDAPEST Г The present paper shows the possibility of using a mixture of chloroform and methanol to obtain a mixed phospholipid fraction (LJ and an acetone extractable fraction (Lo) from KCl myosin. The main, P-contain component of Lj is lecithin, while_t2 consists almost entirely of phosphatidyl ethanolamine. More than 60% of the fatty acids in the latter are unsaturated and can be autooxidised much more completely than in L,. Both lipids are native, and develop myelin figures in polarization exposures: these take the form of interaction crystals or aggregates under the influence of basic amino acids, and of chelate type crystals or aggregates of different anisotropy when exposed to metal ions. The interaction and chelate crystals of lipids, as well as the existence of the chelate model of myosin indicate that lipid is an integral part of the myosin molecule and the specific lipids take part in maintaining the structure and enzyme activity of protein. Through the metal ions, on the other hand, the changed relation of lipids and protein has a modifying effect on the individual phases of the enzyme activity. Introduction According to LYNN (1965) myosin has a 4% lipid content which cannot be removed, but only reduced with lipid solvents. Our experiments showed a much higher lipid content even in chromatographically purified myosin. In fact, a considerable amount of lipid is removed in each phase of purification, yet the purified myosin is obtained with a definite lipid content. When extracted with a mixture of Chi : MeO II the lipid content of myosin can only be substantially reduced after a long process of treatment. Chromatographic purification, however, resulted in several myosin fractions with different lipid contents and ATP-ase activities. The lipid of myosin is mainly lecithin and phosphatidyl ethanolamine. In the open air the isolated lipid quickly peroxidizes and its Ilf-value, on a TLC plate covered with Silica G, undergoes a change. The fluorescence maximum of peroxidized lipids shifts to higher wavelengths and always breaks up into several maxima showing the heterogeneity of these lipids (FAZEKAS et al. 1973). Acta Agronomica Academiae Scientiarum Hungaricae 27, 1978 1