ROUGHNESS OF THE GLOBULAR PROTEIN SURFACE

The area and volume of the approximating ellipsoids taken from low res olution X-ray data have been calculated for 65 globular proteins. It h as been shown that the dependence of these values on the protein molec ular mass (M) coincides with those for even isometric bodies. This ind icates that the asymmetry of globular proteins does not grow with the increase of their sizes. At the same time the 0,73 slope of the log-lo g dependence of the accessible surface area (A(s)) on the protein mole cular mass differing from the value of 0,67 for even isometric bodies was observed (Miller S. et al., J. Mol. Biol. 1987. V.196. P.641). Thi s can be explained by peculiarities of the protein surface. The method of molecule shape recovery by spherical harmonics has shown that the domain organization of protein molecule cannot explain the observed di fference. Therefore the more detailed analysis of protein surface stru cture would be necessary.