Conformational order of specific phospholipids in human erythrocytes: Correlations with changes in cell shape

David J. Moore, Richard H. Sills, Richard Mendelsohn

Research output: Contribution to journalArticlepeer-review

22 Scopus citations

Abstract

Acyl chain perdeuterated dimyristoylphosphatidylcholine (DMPC-d54) and dimyristoylphosphatidylserine (DMPS-d54) were incorporated into human erythrocytes. Light microscopy demonstrated that erythrocytes incubated with an equimolar mixture of DMPC-d54/DMPS or DMPC/DMPS-d54 remained mostly discocytic whereas cells incubated with either DMPC-d54 or DMPS-d54 alone became echinocytic or stomatocytic, respectively. Cells in which the aminophospholipid translocating protein was inhibited became echinocytic when incubated with DMPS-d54. Fourier transform infrared (FTIR) spectroscopy was used to monitor conformational order in the acyl chains of the incorporated phospholipid, as detected through the asymmetric CD2 stretching vibrations in the intact cells. In cells incubated with equimolar mixtures of DMPC- d54/DMPS or DMPC/DMPS-d54, the deuterated species exhibited no thermotropic phase transitions but revealed chain order intermediate between the gel and liquid-crystal states. In contrast, DMPS-d54 incorporated into the outer leaflet of echinocytic erythrocytes was conformationally ordered while the same species incorporated into the inner leaflet of stomatocytic erythrocytes was highly disordered at all temperatures studied. Finally, DMPC-d54 incorporated into the outer leaflet of echinocytic erythrocytes exhibited a phase transition, suggesting that this species persists in domains. These data indicate that the acyl chain conformational order of specific phospholipids in the intact human erythrocyte is changed with alterations in cell morphology.

Original languageEnglish (US)
Pages (from-to)660-664
Number of pages5
JournalBiochemistry
Volume36
Issue number3
DOIs
StatePublished - Jan 21 1997

All Science Journal Classification (ASJC) codes

  • Biochemistry

Fingerprint

Dive into the research topics of 'Conformational order of specific phospholipids in human erythrocytes: Correlations with changes in cell shape'. Together they form a unique fingerprint.

Cite this