DOI: 10.1073/pnas.69.4.930. The Low Polarity of Many Membrane Proteins

The Low Polarity of Many Membrane Proteins

10.1073/pnas.69.4.930

Crossref journal-article

Proceedings of the National Academy of Sciences

Proceedings of the National Academy of Sciences (341)

Abstract

The polarities of a large number of soluble and membrane proteins have been calculated by summing the mole fractions of polar amino acids. It was found that 85% of the 205 soluble proteins considered in this study had polarities of 47 ± 6%. Only 2% of the soluble proteins had polarities below 40%, whereas 47% of the 19 membrane proteins had polarities below 40%. The membrane proteins with polarities below 40% could be separated from their respective membranes only by detergents or organic solvents, indicating the importance of hydrophobic forces in their interaction with other membrane components. It is concluded that the majority of “intrinsic” membrane proteins have low polarity, and that the polarity index is therefore a useful parameter for characterization of membrane proteins.

Bibliography

Capaldi, R. A., & Vanderkooi, G. (1972). The Low Polarity of Many Membrane Proteins. Proceedings of the National Academy of Sciences, 69(4), 930â932.

Authors 2

Roderick A. Capaldi (first)
Garret Vanderkooi (additional)

References 0 Referenced 339

None

Dates

Type	When
Created	19 years, 2 months ago (May 31, 2006, 2:35 a.m.)
Deposited	3 years, 4 months ago (April 13, 2022, 10:41 a.m.)
Indexed	3 weeks, 4 days ago (Aug. 5, 2025, 8:41 a.m.)
Issued	53 years, 4 months ago (April 1, 1972)
Published	53 years, 4 months ago (April 1, 1972)
Published Online	53 years, 4 months ago (April 1, 1972)
Published Print	53 years, 4 months ago (April 1, 1972)

Funders 0

None

BibTeX

@article{Capaldi_1972, title={The Low Polarity of Many Membrane Proteins}, volume={69}, ISSN={1091-6490}, url={http://dx.doi.org/10.1073/pnas.69.4.930}, DOI={10.1073/pnas.69.4.930}, number={4}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Capaldi, Roderick A. and Vanderkooi, Garret}, year={1972}, month=apr, pages={930–932} }

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