Fe2+ promoted peroxidation of 1,2-diacyl-sn-glycero-3-phosphocholine liposomes in the presence of calf thymus DNA.
The peroxidation reaction of some liposomes, namely egg yolk phosphatidylcholine (PC), dioleoyl- (DOPC) and dilinoleoyl- (DLPC) phosphocholines, promoted by ferrous ions (Fenton reaction) has been studied at the physiological pH value, in the absence and in the presence of calf thymus DNA. A catalytic effect of DNA, where the lag time reduces or is completely annihilated, together with an increase in both the yields and the rates of the reactions, has been observed. This effect of DNA has been attributed to the ability of the three components, liposomes, DNA and Fe2+, to form a stable ternary complex, which produces a reduction of the undulatory fluctuations of the hydrocarbon tails of liposomes and strengthens the packing between the acyl chains in the lipid bilayers, with the consequence of enhancing the liposome crystallinity.
Bruni
Paolo
P
Dipartimento di Scienze dei Materiali e della Terra, Università Politecnica delle Marche, Via Brecce Bianche, 60126 Ancona, Italy. p.bruni@univpm.it
Pisani
Michela
M
Iacussi
Marco
M
Francescangeli
Oriano
O
D000215:Acylation; D004247:DNA / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D005990:Glycerol / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D015227:Lipid Peroxidation; D008081:Liposomes / Q000737:chemistry*; D010713:Phosphatidylcholines / Q000737:chemistry*; D013696:Temperature
D005296:Ferrous Compounds; D008081:Liposomes; D010713:Phosphatidylcholines; D004247:DNA; C427203:calf thymus DNA; C017251:1,2-oleoylphosphatidylcholine; D005990:Glycerol