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Updated: Feb 11, 2026

Characterization of Membrane Transporters by Heterologous Expression in E. coli and Production of Membrane Vesicles
Published on: December 31, 2019
[Isolation and characterization of membranes from Methylomonas methanica]
Abstract:
The cell wall (CW), cytoplasmic (CM) and intracytoplasmic membrane (ICM) fractions were obtained by sucrose linear gradient centrifugation of membrane preparations of Methylomonas methanica. The CW fraction represented by large open fragments with 5-layer structure is enriched in lipopolysaccharides and is similar in its protein composition to the CW fractions of other gram-negative bacteria. The CM vesicles are surrounded with a unit membrane, have high activities of marker enzymes (NADH dehydrogenase, succinate dehydrogenase and ATPase), a higher phospholipid content, cytochromes of a-, b- and c-types and differ qualitatively in its protein composition from the CW fraction. The ICM fraction has much in common with the CM fraction but differs from it by a higher level of marker enzymes and cytochromes of b and c types.
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