use of ffx.potential.parsers.PDBFilter.HetAtoms in project ffx by mjschnie.
the class BiojavaFilter method assignAtomTypes.
/**
* Assign force field atoms types to common chemistries using "biotype"
* records.
*/
public void assignAtomTypes() {
/**
* Create a new List to store bonds determined based on PDB atom names.
*/
bondList = new ArrayList<>();
/**
* To Do: Look for cyclic peptides and disulfides.
*/
Polymer[] polymers = activeMolecularAssembly.getChains();
/**
* Loop over chains.
*/
if (polymers != null) {
logger.info(format("\n Assigning atom types for %d chains.", polymers.length));
for (Polymer polymer : polymers) {
List<Residue> residues = polymer.getResidues();
int numberOfResidues = residues.size();
/**
* Check if all residues are known amino acids.
*/
boolean isProtein = true;
if (!residues.isEmpty()) {
// renameNTerminusHydrogens(residues.get(0)); Not safe to use until it distinguishes between true N-termini and N-terminal residues in general.
}
for (int residueNumber = 0; residueNumber < numberOfResidues; residueNumber++) {
Residue residue = residues.get(residueNumber);
String name = residue.getName().toUpperCase();
boolean aa = false;
for (AminoAcid3 amino : aminoAcidList) {
if (amino.toString().equalsIgnoreCase(name)) {
aa = true;
renameNonstandardHydrogens(residue);
break;
}
}
// Check for a patch.
if (!aa) {
HashMap<String, AtomType> types = forceField.getAtomTypes(name);
if (types.isEmpty()) {
isProtein = false;
break;
} else {
logger.info(" Patch found for non-standard amino acid " + name);
}
}
}
/**
* If all the residues in this chain have known amino acids
* names, then attempt to assign atom types.
*/
if (isProtein) {
try {
logger.info(format(" Amino acid chain %s", polymer.getName()));
double dist = properties.getDouble("chainbreak", 3.0);
// Detect main chain breaks!
List<List<Residue>> subChains = findChainBreaks(residues, dist);
for (List<Residue> subChain : subChains) {
assignAminoAcidAtomTypes(subChain);
}
} catch (MissingHeavyAtomException missingHeavyAtomException) {
logger.severe(missingHeavyAtomException.toString());
} catch (MissingAtomTypeException missingAtomTypeException) {
logger.severe(missingAtomTypeException.toString());
}
continue;
}
/**
* Check if all residues have known nucleic acids names.
*/
boolean isNucleicAcid = true;
for (int residueNumber = 0; residueNumber < numberOfResidues; residueNumber++) {
Residue residue = residues.get(residueNumber);
String name = residue.getName().toUpperCase();
/**
* Convert 1 and 2-character nucleic acid names to
* 3-character names.
*/
if (name.length() == 1) {
if (name.equals("A")) {
name = NucleicAcid3.ADE.toString();
} else if (name.equals("C")) {
name = NucleicAcid3.CYT.toString();
} else if (name.equals("G")) {
name = NucleicAcid3.GUA.toString();
} else if (name.equals("T")) {
name = NucleicAcid3.THY.toString();
} else if (name.equals("U")) {
name = NucleicAcid3.URI.toString();
}
} else if (name.length() == 2) {
if (name.equals("YG")) {
name = NucleicAcid3.YYG.toString();
}
}
residue.setName(name);
NucleicAcid3 nucleicAcid = null;
for (NucleicAcid3 nucleic : nucleicAcidList) {
String nuc3 = nucleic.toString();
nuc3 = nuc3.substring(nuc3.length() - 3);
if (nuc3.equalsIgnoreCase(name)) {
nucleicAcid = nucleic;
break;
}
}
if (nucleicAcid == null) {
logger.info(format("Nucleic acid was not recognized %s.", name));
isNucleicAcid = false;
break;
}
}
/**
* If all the residues in this chain have known nucleic acids
* names, then attempt to assign atom types.
*/
if (isNucleicAcid) {
try {
logger.info(format(" Nucleic acid chain %s", polymer.getName()));
assignNucleicAcidAtomTypes(residues);
} catch (MissingHeavyAtomException missingHeavyAtomException) {
logger.severe(missingHeavyAtomException.toString());
} catch (MissingAtomTypeException missingAtomTypeException) {
logger.severe(missingAtomTypeException.toString());
}
}
}
}
// Assign ion atom types.
ArrayList<MSNode> ions = activeMolecularAssembly.getIons();
if (ions != null && ions.size() > 0) {
logger.info(format(" Assigning atom types for %d ions.", ions.size()));
for (MSNode m : ions) {
Molecule ion = (Molecule) m;
String name = ion.getResidueName().toUpperCase();
HetAtoms hetatm = HetAtoms.valueOf(name);
Atom atom = ion.getAtomList().get(0);
if (ion.getAtomList().size() != 1) {
logger.severe(format(" Check residue %s of chain %s.", ion.toString(), ion.getChainID()));
}
try {
switch(hetatm) {
case NA:
atom.setAtomType(findAtomType(2003));
break;
case K:
atom.setAtomType(findAtomType(2004));
break;
case MG:
case MG2:
atom.setAtomType(findAtomType(2005));
break;
case CA:
case CA2:
atom.setAtomType(findAtomType(2006));
break;
case CL:
atom.setAtomType(findAtomType(2007));
break;
case ZN:
case ZN2:
atom.setAtomType(findAtomType(2008));
break;
case BR:
atom.setAtomType(findAtomType(2009));
break;
default:
logger.severe(format(" Check residue %s of chain %s.", ion.toString(), ion.getChainID()));
}
} catch (Exception e) {
String message = "Error assigning atom types.";
logger.log(Level.SEVERE, message, e);
}
}
}
// Assign water atom types.
ArrayList<MSNode> water = activeMolecularAssembly.getWaters();
if (water != null && water.size() > 0) {
logger.info(format(" Assigning atom types for %d waters.", water.size()));
for (MSNode m : water) {
Molecule wat = (Molecule) m;
try {
Atom O = buildHeavy(wat, "O", null, 2001);
Atom H1 = buildHydrogen(wat, "H1", O, 0.96e0, null, 109.5e0, null, 120.0e0, 0, 2002);
H1.setHetero(true);
Atom H2 = buildHydrogen(wat, "H2", O, 0.96e0, H1, 109.5e0, null, 120.0e0, 0, 2002);
H2.setHetero(true);
} catch (Exception e) {
String message = "Error assigning atom types to a water.";
logger.log(Level.SEVERE, message, e);
}
}
}
// Assign small molecule atom types.
ArrayList<Molecule> molecules = activeMolecularAssembly.getMolecules();
for (MSNode m : molecules) {
Molecule molecule = (Molecule) m;
String moleculeName = molecule.getResidueName();
logger.info(" Attempting to patch " + moleculeName);
ArrayList<Atom> moleculeAtoms = molecule.getAtomList();
boolean patched = true;
HashMap<String, AtomType> types = forceField.getAtomTypes(moleculeName);
/**
* Assign atom types for all known atoms.
*/
for (Atom atom : moleculeAtoms) {
String atomName = atom.getName().toUpperCase();
AtomType atomType = types.get(atomName);
if (atomType == null) {
logger.info(" No atom type was found for " + atomName + " of " + moleculeName + ".");
patched = false;
break;
} else {
atom.setAtomType(atomType);
types.remove(atomName);
}
}
/**
* Create missing hydrogen atoms. Check for missing heavy atoms.
*/
if (patched && !types.isEmpty()) {
for (AtomType type : types.values()) {
if (type.atomicNumber != 1) {
logger.info(" Missing heavy atom " + type.name);
patched = false;
break;
}
}
}
// Create bonds between known atoms.
if (patched) {
for (Atom atom : moleculeAtoms) {
String atomName = atom.getName();
String[] bonds = forceField.getBonds(moleculeName, atomName);
if (bonds != null) {
for (String name : bonds) {
Atom atom2 = molecule.getAtom(name);
if (atom2 != null && !atom.isBonded(atom2)) {
buildBond(atom, atom2);
}
}
}
}
}
// Create missing hydrogen atoms.
if (patched && !types.isEmpty()) {
// Create a hashmap of the molecule's atoms
HashMap<String, Atom> atomMap = new HashMap<String, Atom>();
for (Atom atom : moleculeAtoms) {
atomMap.put(atom.getName().toUpperCase(), atom);
}
for (String atomName : types.keySet()) {
AtomType type = types.get(atomName);
String[] bonds = forceField.getBonds(moleculeName, atomName.toUpperCase());
if (bonds == null || bonds.length != 1) {
patched = false;
logger.info(" Check biotype for hydrogen " + type.name + ".");
break;
}
// Get the heavy atom the hydrogen is bonded to.
Atom ia = atomMap.get(bonds[0].toUpperCase());
Atom hydrogen = new Atom(0, atomName, ia.getAltLoc(), new double[3], ia.getResidueName(), ia.getResidueNumber(), ia.getChainID(), ia.getOccupancy(), ia.getTempFactor(), ia.getSegID());
logger.fine(" Created hydrogen " + atomName + ".");
hydrogen.setAtomType(type);
hydrogen.setHetero(true);
molecule.addMSNode(hydrogen);
int valence = ia.getAtomType().valence;
List<Bond> aBonds = ia.getBonds();
int numBonds = aBonds.size();
/**
* Try to find the following configuration: ib-ia-ic
*/
Atom ib = null;
Atom ic = null;
Atom id = null;
if (numBonds > 0) {
Bond bond = aBonds.get(0);
ib = bond.get1_2(ia);
}
if (numBonds > 1) {
Bond bond = aBonds.get(1);
ic = bond.get1_2(ia);
}
if (numBonds > 2) {
Bond bond = aBonds.get(2);
id = bond.get1_2(ia);
}
/**
* Building the hydrogens depends on hybridization and the
* locations of other bonded atoms.
*/
logger.fine(" Bonding " + atomName + " to " + ia.getName() + " (" + numBonds + " of " + valence + ").");
switch(valence) {
case 4:
switch(numBonds) {
case 3:
// Find the average coordinates of atoms ib, ic and id.
double[] b = ib.getXYZ(null);
double[] c = ib.getXYZ(null);
double[] d = ib.getXYZ(null);
double[] a = new double[3];
a[0] = (b[0] + c[0] + d[0]) / 3.0;
a[1] = (b[1] + c[1] + d[1]) / 3.0;
a[2] = (b[2] + c[2] + d[2]) / 3.0;
// Place the hydrogen at chiral position #1.
intxyz(hydrogen, ia, 1.0, ib, 109.5, ic, 109.5, 1);
double[] e1 = new double[3];
hydrogen.getXYZ(e1);
double[] ret = new double[3];
diff(a, e1, ret);
double l1 = r(ret);
// Place the hydrogen at chiral position #2.
intxyz(hydrogen, ia, 1.0, ib, 109.5, ic, 109.5, -1);
double[] e2 = new double[3];
hydrogen.getXYZ(e2);
diff(a, e2, ret);
double l2 = r(ret);
// Revert to #1 if it is farther from the average.
if (l1 > l2) {
hydrogen.setXYZ(e1);
}
break;
case 2:
intxyz(hydrogen, ia, 1.0, ib, 109.5, ic, 109.5, 0);
break;
case 1:
intxyz(hydrogen, ia, 1.0, ib, 109.5, null, 0.0, 0);
break;
case 0:
intxyz(hydrogen, ia, 1.0, null, 0.0, null, 0.0, 0);
break;
default:
logger.info(" Check biotype for hydrogen " + atomName + ".");
patched = false;
}
break;
case 3:
switch(numBonds) {
case 2:
intxyz(hydrogen, ia, 1.0, ib, 120.0, ic, 0.0, 0);
break;
case 1:
intxyz(hydrogen, ia, 1.0, ib, 120.0, null, 0.0, 0);
break;
case 0:
intxyz(hydrogen, ia, 1.0, null, 0.0, null, 0.0, 0);
break;
default:
logger.info(" Check biotype for hydrogen " + atomName + ".");
patched = false;
}
break;
case 2:
switch(numBonds) {
case 1:
intxyz(hydrogen, ia, 1.0, ib, 120.0, null, 0.0, 0);
break;
case 0:
intxyz(hydrogen, ia, 1.0, null, 0.0, null, 0.0, 0);
break;
default:
logger.info(" Check biotype for hydrogen " + atomName + ".");
patched = false;
}
break;
case 1:
switch(numBonds) {
case 0:
intxyz(hydrogen, ia, 1.0, null, 0.0, null, 0.0, 0);
break;
default:
logger.info(" Check biotype for hydrogen " + atomName + ".");
patched = false;
}
break;
default:
logger.info(" Check biotype for hydrogen " + atomName + ".");
patched = false;
}
if (!patched) {
break;
} else {
buildBond(ia, hydrogen);
}
}
}
if (!patched) {
logger.log(Level.WARNING, format(" Deleting unrecognized molecule %s.", m.toString()));
activeMolecularAssembly.deleteMolecule((Molecule) m);
} else {
logger.info(" Patch for " + moleculeName + " succeeded.");
}
}
}
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