Year: 2002
Type: article
Abstract: The 12 Å resolution structure of the detergent in crystals of monomeric outer membrane phospholipase A (OMPLA) has been determined using neutron diffraction.Five large single OMPLA crystals were soaked in stabilizing solutions containing different ratios H2O/D2O, thus obtaining distinct neutron scattering contrasts.From the diffraction data at these contrasts, the structure of the detergent micelles was determined.The hydrophobic β -barrel surfaces of the protein molecules are covered by rings of detergent.These detergent belts are fused to neighbouring detergent rings forming a continuous threedimensional network throughout the crystal.The thickness of the detergent layer around the protein varies from 7 to 20 Å.The enzyme's active site is positioned just outside the hydrophobic detergent zone and is thus in a proper location to catalyze the hydrolysis of phospholipids in a natural membrane.The dimerization face of OMPLA is covered with detergent, but the detergent density is weak near the exposed polar patch suggesting that burying this patch in the enzyme dimer interface may be favorable.Furthermore, this study presents the first example a third type of membrane protein crystal of which the detergent structure is determined and therefore is valuable for a more complete understanding of membrane protein crystallization.
Author: S. Teichmann
Institution: MRC Laboratory of Molecular Biology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2088964841