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. 1970 Jul;66(3):909–916. doi: 10.1073/pnas.66.3.909

Membrane Structure: Spin Labeling and Freeze Etching of Mycoplasma laidlawii*

Mark E Tourtellotte 1,2,†, Daniel Branton 1,2, Alec Keith 1,2
PMCID: PMC283137  PMID: 4316683

Abstract

A spin-labeled fatty acid was incorporated in vivo into the polar lipids of Mycoplasma laidlawii membranes. The electron paramagnetic resonance signal from either intact cells or their extracted lipids reflected the fatty acid composition of the Mycoplasma membranes. Comparison of signals from intact cells, gramicidin-treated cells, heat-treated cells, and extracted lipids indicates that a major portion of the membrane lipids is in a semiviscous hydrocarbon environment. The results also show that the spin label in the intact membrane is slightly but significantly less mobile than it is in protein-free lipid extracts made from these membranes. Correlated electron microscope examinations using the freeze-etch technique reveal particulate components in the hydrophobic region of the membrane. The mobility of the lipids in the intact cell membrane may be influenced by their association with these particles.

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Selected References

These references are in PubMed. This may not be the complete list of references from this article.

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