The pretransition of dipalmitoyllecithin bilayers as probed by the fluorescent pyrrolopyrimidine, U-104067

Chemistry and Physics of Lipids
D E EppsF J Kézdy

Abstract

The amphiphilic pyrrolopyrimidine, U-104067, is a fluorophore ideally suited to report on the relative hydrophobicities of different microenvironments. It forms stable monomolecular layers at the air/water interface with a limiting molecular area of 51.9 +/- 0.3 A2/molecule and a collapse pressure of about 18 dyn/cm. Differential scanning calorimetry of its mixed liposomes with dipalmitoyllecithin shows full solubility of the compound in the liquid disordered phase and insolubility in the solid ordered phase. In aqueous solutions, the compound binds to phospholipid bilayers with a stoichiometry of 13.2 +/- 1.2 moles of lipid per mole of U-104067, with Kd = 0.33 +/- 0.05 microM toward egg lecithin/phosphatidylserine bilayers and Kd = 1.5 +/- 0.3 microM toward pure egg lecithin bilayers. In liquid crystalline phospholipid bilayers the compound behaves as two independently emitting species, one accessible to acrylamide and the other one not. Doxyl fatty acid methyl esters quench both species and show that the average position of the fluorophore is at a depth corresponding to that of the 7th carbon of a fatty acyl chain. Dissolved in the liquid disordered (L alpha) phase of dipalmitoyllecithin at 45 degrees C, U-104067 shows a sing...Continue Reading

References

Dec 16, 1986·Biochimica Et Biophysica Acta·A OrtizJ C Gómez-Fernández

❮ Previous
Next ❯

Citations


❮ Previous
Next ❯

Related Concepts

Trending Feeds

COVID-19

Coronaviruses encompass a large family of viruses that cause the common cold as well as more serious diseases, such as the ongoing outbreak of coronavirus disease 2019 (COVID-19; formally known as 2019-nCoV). Coronaviruses can spread from animals to humans; symptoms include fever, cough, shortness of breath, and breathing difficulties; in more severe cases, infection can lead to death. This feed covers recent research on COVID-19.

Blastomycosis

Blastomycosis fungal infections spread through inhaling Blastomyces dermatitidis spores. Discover the latest research on blastomycosis fungal infections here.

Nuclear Pore Complex in ALS/FTD

Alterations in nucleocytoplasmic transport, controlled by the nuclear pore complex, may be involved in the pathomechanism underlying multiple neurodegenerative diseases including Amyotrophic Lateral Sclerosis and Frontotemporal Dementia. Here is the latest research on the nuclear pore complex in ALS and FTD.

Applications of Molecular Barcoding

The concept of molecular barcoding is that each original DNA or RNA molecule is attached to a unique sequence barcode. Sequence reads having different barcodes represent different original molecules, while sequence reads having the same barcode are results of PCR duplication from one original molecule. Discover the latest research on molecular barcoding here.

Chronic Fatigue Syndrome

Chronic fatigue syndrome is a disease characterized by unexplained disabling fatigue; the pathology of which is incompletely understood. Discover the latest research on chronic fatigue syndrome here.

Evolution of Pluripotency

Pluripotency refers to the ability of a cell to develop into three primary germ cell layers of the embryo. This feed focuses on the mechanisms that underlie the evolution of pluripotency. Here is the latest research.

Position Effect Variegation

Position Effect Variagation occurs when a gene is inactivated due to its positioning near heterochromatic regions within a chromosome. Discover the latest research on Position Effect Variagation here.

STING Receptor Agonists

Stimulator of IFN genes (STING) are a group of transmembrane proteins that are involved in the induction of type I interferon that is important in the innate immune response. The stimulation of STING has been an active area of research in the treatment of cancer and infectious diseases. Here is the latest research on STING receptor agonists.

Microbicide

Microbicides are products that can be applied to vaginal or rectal mucosal surfaces with the goal of preventing, or at least significantly reducing, the transmission of sexually transmitted infections. Here is the latest research on microbicides.