molstar
Version:
A comprehensive macromolecular library.
120 lines • 6.72 kB
JavaScript
/**
* Copyright (c) 2019 mol* contributors, licensed under MIT, See LICENSE file for more info.
*
* @author Sebastian Bittrich <sebastian.bittrich@rcsb.org>
* @author Alexander Rose <alexander.rose@weirdbyte.de>
*/
import { __assign, __awaiter, __generator } from "tslib";
import { Task } from '../../../mol-task';
// import { BitFlags } from '../../../mol-util';
import { ParamDefinition as PD } from '../../../mol-util/param-definition';
import { Vec3 } from '../../../mol-math/linear-algebra';
import { StructureProperties } from '../../../mol-model/structure';
import { assignRadiusForHeavyAtoms } from './shrake-rupley/radii';
import { VdWLookup, MaxAsa, DefaultMaxAsa } from './shrake-rupley/common';
import { computeArea } from './shrake-rupley/area';
import { SortedArray } from '../../../mol-data/int';
export var ShrakeRupleyComputationParams = {
numberOfSpherePoints: PD.Numeric(92, { min: 12, max: 360, step: 1 }, { description: 'Number of sphere points to sample per atom: 92 (original paper), 960 (BioJava), 3000 (EPPIC) - see Shrake A, Rupley JA: Environment and exposure to solvent of protein atoms. Lysozyme and insulin. J Mol Biol 1973.' }),
probeSize: PD.Numeric(1.4, { min: 0.1, max: 4, step: 0.01 }, { description: 'Corresponds to the size of a water molecule: 1.4 (original paper), 1.5 (occassionally used)' }),
// buriedRasaThreshold: PD.Numeric(0.16, { min: 0.0, max: 1.0 }, { description: 'below this cutoff of relative accessible surface area a residue will be considered buried - see: Rost B, Sander C: Conservation and prediction of solvent accessibility in protein families. Proteins 1994.' }),
nonPolymer: PD.Boolean(false, { description: 'Include non-polymer atoms as occluders.' }),
traceOnly: PD.Boolean(false, { description: 'Compute only using alpha-carbons, if true increase probeSize accordingly (e.g., 4 A). Considers only canonical amino acids.' })
};
// TODO
// - add back buried and relative asa
export { AccessibleSurfaceArea };
var AccessibleSurfaceArea;
(function (AccessibleSurfaceArea) {
/**
* Adapts the BioJava implementation by Jose Duarte. That implementation is based on the publication by Shrake, A., and
* J. A. Rupley. "Environment and Exposure to Solvent of Protein Atoms. Lysozyme and Insulin." JMB (1973).
*/
function compute(structure, props) {
var _this = this;
if (props === void 0) { props = {}; }
var p = __assign(__assign({}, PD.getDefaultValues(ShrakeRupleyComputationParams)), props);
return Task.create('Compute Accessible Surface Area', function (runtime) { return __awaiter(_this, void 0, void 0, function () {
return __generator(this, function (_a) {
switch (_a.label) {
case 0: return [4 /*yield*/, calculate(runtime, structure, p)];
case 1: return [2 /*return*/, _a.sent()];
}
});
}); });
}
AccessibleSurfaceArea.compute = compute;
function calculate(runtime, structure, props) {
return __awaiter(this, void 0, void 0, function () {
var ctx, area, serialResidueIndex;
return __generator(this, function (_a) {
switch (_a.label) {
case 0:
ctx = initialize(structure, props);
assignRadiusForHeavyAtoms(ctx);
return [4 /*yield*/, computeArea(runtime, ctx)];
case 1:
_a.sent();
area = ctx.area, serialResidueIndex = ctx.serialResidueIndex;
return [2 /*return*/, { area: area, serialResidueIndex: serialResidueIndex }];
}
});
});
}
function initialize(structure, props) {
var elementCount = structure.elementCount, atomicResidueCount = structure.atomicResidueCount;
var probeSize = props.probeSize, nonPolymer = props.nonPolymer, traceOnly = props.traceOnly, numberOfSpherePoints = props.numberOfSpherePoints;
return {
structure: structure,
probeSize: probeSize,
nonPolymer: nonPolymer,
traceOnly: traceOnly,
spherePoints: generateSpherePoints(numberOfSpherePoints),
scalingConstant: 4.0 * Math.PI / numberOfSpherePoints,
maxLookupRadius: 2 * props.probeSize + 2 * VdWLookup[2],
atomRadiusType: new Int8Array(elementCount),
serialResidueIndex: new Int32Array(elementCount),
area: new Float32Array(atomicResidueCount)
};
}
/** Creates a collection of points on a sphere by the Golden Section Spiral algorithm. */
function generateSpherePoints(numberOfSpherePoints) {
var points = [];
var inc = Math.PI * (3.0 - Math.sqrt(5.0));
var offset = 2.0 / numberOfSpherePoints;
for (var k = 0; k < numberOfSpherePoints; ++k) {
var y = k * offset - 1.0 + (offset / 2.0);
var r = Math.sqrt(1.0 - y * y);
var phi = k * inc;
points[points.length] = Vec3.create(Math.cos(phi) * r, y, Math.sin(phi) * r);
}
return points;
}
/** Get relative area for a given component id */
function normalize(compId, asa) {
var maxAsa = MaxAsa[compId] || DefaultMaxAsa;
return asa / maxAsa;
}
AccessibleSurfaceArea.normalize = normalize;
function getValue(location, accessibleSurfaceArea) {
var area = accessibleSurfaceArea.area, serialResidueIndex = accessibleSurfaceArea.serialResidueIndex;
var rSI = serialResidueIndex[SortedArray.indexOf(SortedArray.ofSortedArray(location.structure.root.serialMapping.elementIndices), location.element)];
if (rSI === -1)
return -1;
return area[rSI];
}
AccessibleSurfaceArea.getValue = getValue;
function getNormalizedValue(location, accessibleSurfaceArea) {
var value = getValue(location, accessibleSurfaceArea);
return value === -1 ? -1 : normalize(StructureProperties.atom.label_comp_id(location), value);
}
AccessibleSurfaceArea.getNormalizedValue = getNormalizedValue;
function getFlag(location, accessibleSurfaceArea) {
var value = getNormalizedValue(location, accessibleSurfaceArea);
return value === -1 ? 0 /* NA */ :
value < 0.16 ? 1 /* Buried */ :
2 /* Accessible */;
}
AccessibleSurfaceArea.getFlag = getFlag;
})(AccessibleSurfaceArea || (AccessibleSurfaceArea = {}));
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