Structural investigation of frozen-hydrated Omp C specimens prepared by the fatty acid monolayer technique

Journal Article · Sat Jan 01 04:00:00 EST 1983 · Proc. - Annu. Meet., Electron Microsc. Soc. Am.; (United States)

OSTI ID:6272099

Chang, C F; Glaeser, R M

Omp C (M.W. approx.36,000) is one of the major proteins in the outer membrane of E. coli. Trimeric Omp C forms a pore allowing small hydrophilic molecules to diffuse across the membrane. Specimens studied are prepared by reconstituting purified Omp C trimers with lipid A (the core structure of the outer membrane lipopolysaccharide). These specimens form 2-D periodic arrays with a size of approx.0.5 ..mu..m on edge. Initial structural investigations on negatively stained Omp C specimens have been reported by Grano et al. A preliminary structural analysis of frozen-hydrated Omp C is presented, using specimens prepared by a modification of the stearic-acid monolayer technique of Hayward et al. Stearate monolayers can successfully squeeze out the bulk water on the surface of the EM grid only at relatively high concentrations of Ca/sup + +/ and high pH. In the current study, the authors replaced the stearic acid with behenic acid, CH/sub 3/(CH/sub 2/)/sub 20/COOH, which can adhere to a suitably prepared EM grid from a subphase of distilled water.

• Research Organization: Lawrence Berkeley Laboratory, CA
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 6272099
• Journal Information: Proc. - Annu. Meet., Electron Microsc. Soc. Am.; (United States), Journal Name: Proc. - Annu. Meet., Electron Microsc. Soc. Am.; (United States) Vol. 41; ISSN EMSPA
• Country of Publication: United States
• Language: English

Related Subjects

550000* -- Biomedical Sciences
Basic Studies
59 BASIC BIOLOGICAL SCIENCES
BACTERIA
BIOCHEMICAL REACTION KINETICS
CARBOHYDRATES
CELL CONSTITUENTS
CELL MEMBRANES
ELECTRON MICROSCOPY
ESCHERICHIA COLI
IMAGES
KINETICS
LIPIDS
LIPOPOLYSACCHARIDES
MEMBRANES
MICROORGANISMS
MICROSCOPY
ORGANIC COMPOUNDS
POLYSACCHARIDES
PROTEINS
REACTION KINETICS
SACCHARIDES
SAMPLE PREPARATION