Intermittent contact mode AFM investigation of native plasma membrane of Xenopus laevis oocyte

• Published in: European biophysics journal Vol. 38; no. 7; pp. 903 - 910
• Main Authors: Orsini, Francesco, Santacroce, M, Arosio, P, Castagna, M, Lenardi, C, Poletti, G, Sacchi, F. V
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01.09.2009; Springer-Verlag; Springer Nature B.V
• Subjects: Adsorption; Aluminum Silicates - chemistry; Animals; Biochemistry; Biological and Medical Physics; Biomedical and Life Sciences; Biophysics; Cell Biology; Cell Membrane - metabolism; Crystallography, X-Ray; Female; Life Sciences; Lipid Bilayers - chemistry; Lipid Bilayers - metabolism; Lipids; Membrane Biology; Membrane Proteins - chemistry; Membrane Proteins - metabolism; Membranes; Microscopy; Microscopy, Atomic Force; Nanotechnology; Neurobiology; Oocytes - cytology; Original Paper; Plasma; Proteins; Sucrose - chemistry; Time Factors; Ultracentrifugation; Xenopus laevis; Atomic force microscopy (AFM); oocyte; Plasma membrane; Membrane proteins
• ISSN: 0175-7571; 1432-1017
• DOI: 10.1007/s00249-009-0464-7

Intermittent contact mode atomic force microscopy (AFM) was used to visualize the native plasma membrane of Xenopus laevis oocytes. Oocyte membranes were purified via ultracentrifugation on a sucrose gradient and adsorbed on mica leaves. AFM topographs and the corresponding phase images allowed for visualization and identification of both oocyte plasma membrane patches and pure lipid bilayer regions with a height of about 5 nm within membrane patches. The quantitative analysis showed a normal distribution for the lateral dimension and height of the protein complexes centered on 16.7 ± 0.2 nm (mean ± SE, n = 263) and 5.4 ± 0.1 nm (n = 262), respectively. The phase signal, providing material-dependent information, allowed for the recognition of structural features observed in AFM topographs.