package HackaMol;
#ABSTRACT: HackaMol: Object-Oriented Library for Molecular Hacking
use 5.008;
use Moose;
use HackaMol::AtomGroup;
use HackaMol::Molecule;
use HackaMol::Atom;
use HackaMol::Bond;
use HackaMol::Angle;
use HackaMol::Dihedral;
use Scalar::Util qw(refaddr);
use Carp;
with 'HackaMol::NameRole', 'HackaMol::MolReadRole';
sub build_bonds {
#take a list of n, atoms; walk down list and generate bonds
my $self = shift;
my @atoms = @_;
croak "<2 atoms passed to build_dihedrals" unless ( @atoms > 1 );
my @bonds;
# build the bonds
my $k = 0;
while ( $k + 1 <= $#atoms ) {
my $name =
join( "_", map { _name_resid($_,'B')} @atoms[ $k .. $k + 1 ] );
push @bonds,
HackaMol::Bond->new(
name => $name,
atoms => [ @atoms[ $k, $k + 1 ] ]
);
$k++;
}
return (@bonds);
}
sub build_angles {
#take a list of n, atoms; walk down list and generate angles
my $self = shift;
my @atoms = @_;
croak "<3 atoms passed to build_dihedrals" unless ( @atoms > 2 );
my @angles;
# build the angles
my $k = 0;
while ( $k + 2 <= $#atoms ) {
my $name =
join( "_", map { _name_resid($_,'A')} @atoms[ $k .. $k + 2 ] );
push @angles,
HackaMol::Angle->new(
name => $name,
atoms => [ @atoms[ $k .. $k + 2 ] ]
);
$k++;
}
return (@angles);
}
sub _name_resid {
my $atom = shift;
my $default = shift;
return ($default . $atom->resid) unless $atom->has_name;
return ($atom->name . $atom->resid);
}
sub build_dihedrals {
#take a list of n, atoms; walk down list and generate dihedrals
my $self = shift;
my @atoms = @_;
croak "<4 atoms passed to build_dihedrals" unless ( @atoms > 3 );
my @dihedrals;
# build the dihedrals
my $k = 0;
while ( $k + 3 <= $#atoms ) {
my $name =
join( "_", map { _name_resid($_,'D')} @atoms[ $k .. $k + 3 ] );
push @dihedrals,
HackaMol::Dihedral->new(
name => $name,
atoms => [ @atoms[ $k .. $k + 3 ] ]
);
$k++;
}
return (@dihedrals);
}
sub group_by_atom_attr {
# group atoms by attribute
# Z, name, bond_count, etc.
my $self = shift;
my $attr = shift;
my @atoms = @_;
my %group;
foreach my $atom (@atoms) {
push @{ $group{ $atom->$attr } }, $atom;
}
my @atomgroups =
map { HackaMol::AtomGroup->new( atoms => $group{$_} ) } sort
keys(%group);
return (@atomgroups);
}
sub find_bonds_brute {
my $self = shift;
my %args = @_;
my @bond_atoms = @{ $args{bond_atoms} };
my @atoms = @{ $args{candidates} };
my $fudge = 0.45;
my $max_bonds = 99;
$fudge = $args{fudge} if ( exists( $args{fudge} ) );
$max_bonds = $args{max_bonds} if ( exists( $args{max_bonds} ) );
my @init_bond_counts = map {$_->bond_count} (@bond_atoms,@atoms);
my @bonds;
my %name;
foreach my $at_i (@bond_atoms) {
next if ($at_i->bond_count >= $max_bonds);
my $cov_i = $at_i->covalent_radius;
my $xyz_i = $at_i->xyz;
foreach my $at_j (@atoms) {
next if ( refaddr($at_i) == refaddr($at_j) );
next if ($at_j->bond_count >= $max_bonds);
my $cov_j = $at_j->covalent_radius;
my $dist = $at_j->distance($at_i);
if ( $dist <= $cov_i + $cov_j + $fudge ) {
my $nm = $at_i->symbol . "-" . $at_j->symbol;
$name{$nm}++;
push @bonds,
HackaMol::Bond->new(
name => "$nm\_" . $name{$nm},
atoms => [ $at_i, $at_j ],
);
$at_i->inc_bond_count;
$at_j->inc_bond_count;
}
}
}
my $i = 0;
foreach my $at (@bond_atoms,@atoms){
$at->reset_bond_count;
$at->inc_bond_count($init_bond_counts[$i]);
$i++;
}
return (@bonds);
}
__PACKAGE__->meta->make_immutable;
1;
__END__
=pod
=head1 NAME
HackaMol - HackaMol: Object-Oriented Library for Molecular Hacking
=head1 VERSION
version 0.00_05
=head1 SYNOPSIS
use HackaMol;
use Math::Vector::Real;
use Math::Vector::Real::Random;
use Math::Trig;
my $hack = HackaMol->new( name => "hackitup" );
my @atoms = $hack->read_file_atoms("t/lib/1L2Y.pdb");
# all coordinates from NMR ensemble are loaded into atoms
my $mol = HackaMol::Molecule->new(
name => 'trp-cage',
atoms => [@atoms]
);
#recenter all coordinates to center of mass
foreach my $t ( 0 .. $atoms[0]->count_coords - 1 ) {
$mol->t($t);
$mol->translate( -$mol->COM );
}
# print coordinates from t=0 to trp-cage.xyz and return filehandle
my $fh = $mol->print_xyz( $mol->name . ".xyz" );
# print coordinates for @t=(1..4) to same filehandle
foreach my $t ( 1 .. 4 ) {
$mol->t($t);
$mol->print_xyz($fh);
}
$mol->t(0);
foreach ( 1 .. 10 ) {
$mol->rotate(
V( 0, 0, 1 ), # rotation vector
36, # rotate by 36 degrees
V( 5, 0, 0 ) # origin of rotation
);
$mol->print_xyz($fh);
}
# translate/rotate method is provided by AtomGroupRole
# populate groups byatom resid attr
my @groups = $hack->group_by_atom_attr( 'resid', $mol->all_atoms );
$mol->push_groups(@groups);
# silly rotation of sidechains about their own center of mass
foreach my $ang ( 1 .. 10 ) {
$_->rotate( V( 1, 1, 1 ), 36, $_->COM ) foreach $mol->all_groups;
$mol->print_xyz($fh);
}
$fh->close; # done filling trp-cage.xyz with coordinates
#example/hackamol_synopsis.pl picks up from here
=head1 DESCRIPTION
The HackaMol library enables users to build simple, yet powerful scripts
for carrying out computational work on molecules at multiple scales. The
molecular object system organizes atoms within molecules using groups,
bonds, angles, and dihedrals. HackaMol seeks to provide intuitive
attributes and methods that may be harnessed to coerce molecular computation
through a common core. The library is inspired by L<PerlMol|http://www.perl.org>, L<BioPerl|http://bioperl.org>, L<MMTSB|http://www.mmtsb.org>, and my own experiences as a researcher.
The library is organized into two regions: HackaMol, the core (contained here)
that has classes for atoms and molecules, and HackaMolX, the extensions, such as
HackaMolX::PDB, a parser for protein databank files, and HackaMolX::Calculator,
an abstract calculator for coercing molecular computation, that use the core. The three major goals of the core are for it to be well-tested, well-documented, and easy to install. The goal of the extensions is to provide a more flexible space for researchers to develop and share new methods that use the core. Extensions are in the works, but the HackaMolX namespace has not been established yet!
HackaMol uses Math::Vector::Real (MVR) for all the vector operations. MVR is a
lightweight solution with a fast XS dropin that overlaps very well with the
desirables for working with atoms and coarse grained molecules. Extensions that treat much larger systems will definitely benefit from the capabilities L<PDL> or L<Math::GSL>.
The HackaMol class (loaded in Synopsis) uses the core classes to provide some object
building utilities described below. This class consumes HackaMol::MolReadRole to
provide structure readers for xyz and pdb coordinates.
See L<Open Babel|http://openbabel.org> if other formats needed
(All suggestions, contributions welcome!).
=head1 METHODS
=head2 build_bonds
takes a list of atoms and returns a list of bonds. The bonds are generated for
"list neighbors" by simply stepping through the atom list one at a time. e.g.
my @bonds = $hack->build_bonds(@atoms[1,3,5]);
will return two bonds: B13 and B35
=head2 build_angles
takes a list of atoms and returns a list of angles. The angles are generated
analagously to build_bonds, e.g.
my @angles = $hack->build_angles(@atoms[1,3,5]);
will return one angle: A135
=head2 build_dihedrals
takes a list of atoms and returns a list of dihedrals. The dihedrals are generated
analagously to build_bonds, e.g.
my @dihedral = $hack->build_dihedrals(@atoms[1,3,5]);
will croak! you need atleast four atoms.
my @dihedral = $hack->build_dihedrals(@atoms[1,3,5,6,9]);
will return two dihedrals: D1356 and D3569
=head2 group_by_atom_attr
takes atom attribute as argument and builds AtomGroup objects by attribute.
Grouping by graphical searches are needed!
=head2 find_bonds_brute
takes hash argument list and returns bonds. Find bonds between bond_atoms and
the candidates.
my @oxy_bonds = $hack->find_bonds_brute(
bond_atoms => [$hg],
candidates => [$mol->all_atoms],
fudge => 0.45,
max_bonds => 6,
);
fudge is optional with Default is 0.45 (open babel uses same default);
max_bonds is optional with default of 99. max_bonds is compared against
the atom bond count, which are incremented during the search. Before returning
the bonds, the bond_count are returned the values before the search. For now,
molecules are responsible for setting the number of bonds in atoms.
find_bonds_brute uses a bruteforce algorithm that tests the interatomic
separation against the sum of the covalent radii + fudge. It will not test
for bond between atoms if either atom has >= max_bonds. It does not return
a self bond for an atom (C< next if refaddr($ati) == refaddr($atj) >).
=head1 ATTRIBUTES
=head2 name
name is a rw str provided by HackaMol::NameRole.
=head1 SEE ALSO
=over 4
=item *
L<HackaMol::Atom>
=item *
L<HackaMol::Bond>
=item *
L<HackaMol::Angle>
=item *
L<HackaMol::Dihedral>
=item *
L<HackaMol::AtomGroup>
=item *
L<HackaMol::Molecule>
=item *
L<Protein Data Bank | http://pdb.org>
=item *
L<VMD | http://www.ks.uiuc.edu/Research/vmd/>
=back
=head1 EXTENDS
=over 4
=item * L<Moose::Object>
=back
=head1 CONSUMES
=over 4
=item * L<HackaMol::MolReadRole>
=item * L<HackaMol::NameRole>
=item * L<HackaMol::NameRole|HackaMol::MolReadRole>
=back
=head1 AUTHOR
Demian Riccardi <demianriccardi@gmail.com>
=head1 COPYRIGHT AND LICENSE
This software is copyright (c) 2013 by Demian Riccardi.
This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.
=cut