Detail of "20449-79-0"

Reference

Melittin and the 8-26 fragment

Melittin and the 8-26 fragment. Differences in ionophoric properties as measured by monolayer method. Gevod, V. S.; Birdi, K. S. (Inst. Chem. Technol., Dnepropetrovsk 320005, USSR). Biophys. J., 45(6), 1079-83 (English) 1984. CODEN: BIOJAU. ISSN: 0006-3495. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) Section cross-reference(s): 6 The different phys. properties of monolayers of melittin [20449-79-0] and the 8-26 fragment [58672-95-0] in comparison with their biol. activities are reported. While melittin exhibits strong affinity for anions (Cl), the 8-26 fragments show rather poor anion interaction. The absence of Lys-7 in the 8-26 fragment most likely is the reason for the decrease in Cl ion binding, and this is in agreement with the poor lytic activity of the 8-26 fragment.

Study of the effect of melittin on the thermotropism of dipalmitoylphosphatidylcholine by Raman spectroscopy

Study of the effect of melittin on the thermotropism of dipalmitoylphosphatidylcholine by Raman spectroscopy. Lafleur, Michel; Dasseux, Jean Louis; Pigeon, Marie; Dufourcq, Jean; Pezolet, Michel (Dep. Chim., Univ. Laval, Quebec, PQ G1K 7P4, Can.). Biochemistry, 26(4), 1173-9 (English) 1987. CODEN: BICHAW. ISSN: 0006-2960. DOCUMENT TYPE: Journal CA Section: 4 (Toxicology) Section cross-reference(s): 6 The effect of melittin (Mel) [20449-79-0] on the thermotropic behavior of dipalmitoylphosphatidylcholine (DPPC) [2644-64-6] was studied by Raman spectroscopy. The spectra show that for complexes that were incubated >40° melittin did not penetrate DPPC bilayers in the gel state as an intrinsic protein since that conformation of the lipid acyl chains is just slightly perturbed by the toxin. Instead, at the DPPC/Mel molar ratios investigated (Ri = 5 and 15), Raman results suggest the formation of discoidal particles as complexes of apolipoproteins with phosphatidylcholines. These lipid/protein assemblies are characterized by a high conformational order, low intermol. chain/chain interactions due to the size of the particles, and a low cooperativity of the gel to liq.-cryst. transition. The latter is biphasic for samples studied. It is believed that aggregation of these particles into larger ones occurs when the bilayers become less stable at higher temp. and that melittin is partially embedded into the hydrophobic core of the larger lipid/protein units. The freezing of the dispersion at ~0 ° also causes a reversible aggregation of the particles that leads to formation of domains in which the interchain interactions are very similar to that of the pure lipid. The small particles of DPPC/Mel are also metastable, and with time, they form larger aggregates from which melittin is expulsed.