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# ##### BEGIN GPL LICENSE BLOCK #####
#
#  This program is free software; you can redistribute it and/or
#  modify it under the terms of the GNU General Public License
#  as published by the Free Software Foundation; either version 2
#  of the License, or (at your option) any later version.
#
#  This program is distributed in the hope that it will be useful,
#  but WITHOUT ANY WARRANTY; without even the implied warranty of
#  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#  GNU General Public License for more details.
#
#  You should have received a copy of the GNU General Public License
#  along with this program; if not, write to the Free Software Foundation,
#  Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####

import bpy

class Element:
    '''Element class with properties ([R, G, B], cov_radius, vdw_radius, name)'''
    def __init__(self, color, cov_radius, vdw_radius, name):
        self.color = color
        self.cov_radius = cov_radius
        self.vdw_radius = vdw_radius
        self.name = name

class Atom:
    '''Atom class with properties (serial, name, altloc, resname,chainid,
        resseq, icode, x, y, z, occupancy, tempfactor, element, charge)'''
    
    def __init__(self, serial, name, altloc, resname, chainid, resseq, icode,
                 x, y, z, occupancy, tempfactor, element, charge):
        self.serial = serial
        self.name = name
        self.altloc = altloc
        self.resname = resname
        self.chainid = chainid
        self.resseq = resseq
        self.icode = icode
        self.x = x
        self.y = y
        self.z = z
        self.occupancy = occupancy
        self.tempfactor = tempfactor
        self.element = element
        self.charge = charge

#collection of biomolecules based on model
#all chains in model stored here
class Model:
    '''Model class'''
    def __init__(self, model_id):
        self.model_id = model_id
        self.atoms = {}
        self.atom_count = 0
        self.vert_list = []
        #Dictionary of {vert index: [list of vertex groups it belongs to]}
        #Now element only
        self.vert_group_index = {}
        #Dictionary of {vertex group: number of group members}
        self.vert_group_counts = {}
        self.chains = {}

#new object level class
class Biomolecule:
    '''Biomolecule'''
    def __init__(self, serial):
        self.serial = serial
        self.atom_count = 0
        self.vert_list = []
        self.vert_group_index = {}
        self.vert_group_counts = {}
        self.chain_transforms = {}

#Atom collection
class Chain:
    '''Chain'''
    def __init__(self, chain_id):
        self.chain_id = chain_id
        self.atoms = {}

#Atomic data from http://www.ccdc.cam.ac.uk/products/csd/radii/
#Color palatte adapted from Jmol
#"Element symbol":[[Red, Green, Blue], Covalent radius, van der Waals radius,
#                  Element name]
#Atomic radii are in angstroms (100 pm)
#Unknown covalent radii are assigned 1.5 A, unknown van der Waals radiii are
#assigned 2 A,

atom_data = {
'H' :	Element([1.00000, 1.00000, 1.00000],	0.23,	1.09,	'Hydrogen'  ),
'HE':	Element([0.85098, 1.00000, 1.00000],	1.5 ,	1.4 ,	'Helium'    ),
'LI':	Element([0.80000, 0.50196, 1.00000],	1.28,	1.82,	'Lithium'   ),
'BE':	Element([0.76078, 1.00000, 0.00000],	0.96,	2   ,	'Beryllium' ),
'B' :	Element([1.00000, 0.70980, 0.70980],	0.83,	2   ,	'Boron'     ),
'C' :	Element([0.56471, 0.56471, 0.56471],	0.68,	1.7 ,	'Carbon'    ),
'N' :	Element([0.18824, 0.31373, 0.97255],	0.68,	1.55,	'Nitrogen'  ),
'O' :   Element([1.00000, 0.05098, 0.05098],	0.68,	1.52,	'Oxygen'    ),
'F' :	Element([0.56471, 0.87843, 0.31373],	0.64,	1.47,	'Fluorine'  ),
'NE':	Element([0.70196, 0.89020, 0.96078],	1.5 ,	1.54,	'Neon'      ),
'NA':	Element([0.67059, 0.36078, 0.94902],	1.66,	2.27,	'Sodium'    ),
'MG':	Element([0.54118, 1.00000, 0.00000],	1.41,	1.73,	'Magnesium' ),
'AL':	Element([0.74902, 0.65098, 0.65098],	1.21,	2   ,	'Aluminum'  ),
'SI':	Element([0.94118, 0.78431, 0.62745],	1.2 ,	2.1 ,	'Silicon'   ),
'P' :	Element([1.00000, 0.50196, 0.00000],	1.05,	1.8 ,	'Phosphorus'),
'S' :	Element([1.00000, 1.00000, 0.18824],	1.02,	1.8 ,	'Sulfur'    ),
'CL':	Element([0.12157, 0.94118, 0.12157],	0.99,	1.75,	'Chlorine'  ),
'AR':	Element([0.50196, 0.81961, 0.89020],	1.51,	1.88,	'Argon'     ),
'K' :	Element([0.56078, 0.25098, 0.83137],	2.03,	2.75,	'Potassium' ),
'CA':	Element([0.23922, 1.00000, 0.00000],	1.76,	2   ,	'Calcium'   ),
'SC':	Element([0.90196, 0.90196, 0.90196],	1.7 ,	2   ,	'Scandium'  ),
'TI':	Element([0.74902, 0.76078, 0.78039],	1.6 ,	2   ,	'Titanium'  ),
'V' :	Element([0.65098, 0.65098, 0.67059],	1.53,	2   ,	'Vanadium'  ),
'CR':	Element([0.54118, 0.60000, 0.78039],	1.39,	2   ,	'Chromium'  ),
'MN':	Element([0.61176, 0.47843, 0.78039],	1.61,	2   ,	'Manganese' ),
'FE':	Element([0.87843, 0.40000, 0.20000],	1.52,	2   ,	'Iron'      ),
'CO':	Element([0.94118, 0.56471, 0.62745],	1.26,	2   ,	'Cobalt'    ),
'NI':	Element([0.31373, 0.81569, 0.31373],	1.24,	1.63,	'Nickel'    ),
'CU':	Element([0.78431, 0.50196, 0.20000],	1.32,	1.4 ,	'Copper'    ),
'ZN':	Element([0.49020, 0.50196, 0.69020],	1.22,	1.39,	'Zinc'      ),
'GA':	Element([0.76078, 0.56078, 0.56078],	1.22,	1.87,	'Gallium'   ),
'GE':	Element([0.40000, 0.56078, 0.56078],	1.17,	2   ,	'Germanium' ),
'AS':	Element([0.74118, 0.50196, 0.89020],	1.21,	1.85,	'Arsenic'   ),
'SE':	Element([1.00000, 0.63137, 0.00000],	1.22,	1.9 ,	'Selenium'  ),
'BR':	Element([0.65098, 0.16078, 0.16078],	1.21,	1.85,	'Bromine'   ),
'KR':	Element([0.36078, 0.72157, 0.81961],	1.5 ,	2.02,	'Krypton'   ),
'RB':	Element([0.43922, 0.18039, 0.69020],	2.2 ,	2   ,	'Rubidium'  ),
'SR':	Element([0.00000, 1.00000, 0.00000],	1.95,	2   ,	'Strontium' ),
'Y' :	Element([0.58039, 1.00000, 1.00000],	1.9 ,	2   ,	'Yttrium'   ),
'ZR':	Element([0.58039, 0.87843, 0.87843],	1.75,	2   ,	'Zirconium' ),
'NB':	Element([0.45098, 0.76078, 0.78824],	1.64,	2   ,	'Niobium'   ),
'MO':	Element([0.32941, 0.70980, 0.70980],	1.54,	2   ,	'Molybdenum'),
'TC':	Element([0.23137, 0.61961, 0.61961],	1.47,	2   ,	'Technetium'),
'RU':	Element([0.14118, 0.56078, 0.56078],	1.46,	2   ,	'Ruthenium' ),
'RH':	Element([0.03922, 0.49020, 0.54902],	1.45,	2   ,	'Rhodium'   ),
'PD':	Element([0.00000, 0.41176, 0.52157],	1.39,	1.63,	'Palladium' ),
'AG':	Element([0.75294, 0.75294, 0.75294],	1.45,	1.72,	'Silver'    ),
'CD':	Element([1.00000, 0.85098, 0.56078],	1.44,	1.58,	'Cadmium'   ),
'IN':	Element([0.65098, 0.45882, 0.45098],	1.42,	1.93,	'Indium'    ),
'SN':	Element([0.40000, 0.50196, 0.50196],	1.39,	2.17,	'Tin'       ),
'SB':	Element([0.61961, 0.38824, 0.70980],	1.39,	2   ,	'Antimony'  ),
'TE':	Element([0.83137, 0.47843, 0.00000],	1.47,	2.06,	'Tellurium' ),
'I' :	Element([0.58039, 0.00000, 0.58039],	1.4 ,	1.98,	'Iodine'    ),
'XE':	Element([0.25882, 0.61961, 0.69020],	1.5 ,	2.16,	'Xenon'     ),
'CS':	Element([0.34118, 0.09020, 0.56078],	2.44,	2   ,	'Cesium'    ),
'BA':	Element([0.00000, 0.78824, 0.00000],	2.15,	2   ,	'Barium'    ),
'LA':	Element([0.43922, 0.83137, 1.00000],	2.07,	2   ,	'Lanthanum' ),
'CE':	Element([1.00000, 1.00000, 0.78039],	2.04,	2   ,	'Cerium'    ),
'PR':	Element([0.85098, 1.00000, 0.78039],	2.03,	2   ,	'Praseodymium'),
'ND':	Element([0.78039, 1.00000, 0.78039],	2.01,	2   ,	'Neodymium' ),
'PM':	Element([0.63922, 1.00000, 0.78039],	1.99,	2   ,	'Promethium'),
'SM':	Element([0.56078, 1.00000, 0.78039],	1.98,	2   ,	'Samarium'  ),
'EE':	Element([0.38039, 1.00000, 0.78039],	1.98,	2   ,	'Europium'  ),
'GD':	Element([0.27059, 1.00000, 0.78039],	1.96,	2   ,	'Gadolinium'),
'TB':	Element([0.18824, 1.00000, 0.78039],	1.94,	2   ,	'Terbium'   ),
'DY':	Element([0.12157, 1.00000, 0.78039],	1.92,	2   ,	'Dysprosium'),
'HO':	Element([0.00000, 1.00000, 0.61176],	1.92,	2   ,	'Holmium'   ),
'ER':	Element([0.00000, 0.90196, 0.45882],	1.89,	2   ,	'Erbium'    ),
'TM':	Element([0.00000, 0.83137, 0.32157],	1.9 ,	2   ,	'Thulium'   ),
'YB':	Element([0.00000, 0.74902, 0.21961],	1.87,	2   ,	'Ytterbium' ),
'LU':	Element([0.00000, 0.67059, 0.14118],	1.87,	2   ,	'Lutetium'  ),
'HF':	Element([0.30196, 0.76078, 1.00000],	1.75,	2   ,	'Hafnium'   ),
'TA':	Element([0.30196, 0.65098, 1.00000],	1.7 ,	2   ,	'Tantalum'  ),
'W' :	Element([0.12941, 0.58039, 0.83922],	1.62,	2   ,	'Tungsten'  ),
'RE':	Element([0.14902, 0.49020, 0.67059],	1.51,	2   ,	'Rhenium'   ),
'OS':	Element([0.14902, 0.40000, 0.58824],	1.44,	2   ,	'Osmium'    ),
'IR':	Element([0.09020, 0.32941, 0.52941],	1.41,	2   ,	'Iridium'   ),
'PT':	Element([0.81569, 0.81569, 0.87843],	1.36,	1.72,	'Platinum'  ),
'AU':	Element([1.00000, 0.81961, 0.13725],	1.5 ,	1.66,	'Gold'      ),
'HG':	Element([0.72157, 0.72157, 0.81569],	1.32,	1.55,	'Mercury'   ),
'TL':	Element([0.65098, 0.32941, 0.30196],	1.45,	1.96,	'Thallium'  ),
'PB':	Element([0.34118, 0.34902, 0.38039],	1.46,	2.02,	'Lead'      ),
'BI':	Element([0.61961, 0.30980, 0.70980],	1.48,	2   ,	'Bismuth'   ),
'PO':	Element([0.67059, 0.36078, 0.00000],	1.4 ,	2   ,	'Polonium'  ),
'AT':	Element([0.45882, 0.30980, 0.27059],	1.21,	2   ,	'Astatine'  ),
'RN':	Element([0.25882, 0.50980, 0.58824],	1.5 ,	2   ,	'Radon'     ),
'FR':	Element([0.25882, 0.00000, 0.40000],	2.6 ,	2   ,	'Francium'  ),
'RA':	Element([0.00000, 0.49020, 0.00000],	2.21,	2   ,	'Radium'    ),
'AC':	Element([0.43922, 0.67059, 0.98039],	2.15,	2   ,	'Actinium'  ),
'TH':	Element([0.00000, 0.72941, 1.00000],	2.06,	2   ,	'Thorium'   ),
'PA':	Element([0.00000, 0.63137, 1.00000],	2   ,	2   ,	'Protactinium'),
'U' :	Element([0.00000, 0.56078, 1.00000],	1.96,	1.86,	'Uranium'   ),
'NP':	Element([0.00000, 0.50196, 1.00000],	1.9 ,	2   ,	'Neptunium' ),
'PU':	Element([0.00000, 0.41961, 1.00000],	1.87,	2   ,	'Plutonium' ),
'AM':	Element([0.32941, 0.36078, 0.94902],	1.8 ,	2   ,	'Americium' ),
'CM':	Element([0.47059, 0.36078, 0.89020],	1.69,	2   ,	'Curium'    ),
'BK':	Element([0.54118, 0.30980, 0.89020],	1.54,	2   ,	'Berkelium' ),
'CF':	Element([0.63137, 0.21176, 0.83137],	1.83,	2   ,	'Californium'),
'ES':	Element([0.70196, 0.12157, 0.83137],	1.5 ,	2   ,	'Einsteinium'),
'FM':	Element([0.70196, 0.12157, 0.72941],	1.5 ,	2   ,	'Fermium'   ),
'MD':	Element([0.70196, 0.05098, 0.65098],	1.5 ,	2   ,	'Mendelevium'),
'NO':	Element([0.74118, 0.05098, 0.52941],	1.5 ,	2   ,	'Nobelium'  ),
'LR':	Element([0.78039, 0.00000, 0.40000],	1.5 ,	2   ,	'Lawrencium'),
'RF':	Element([0.80000, 0.00000, 0.34902],	1.5 ,	2   ,	'Rutherfordium'),
'DB':	Element([0.81961, 0.00000, 0.30980],	1.5 ,	2   ,	'Dubnium'   ),
'SG':	Element([0.85098, 0.00000, 0.27059],	1.5 ,	2   ,	'Seaborgium'),
'BH':	Element([0.87843, 0.00000, 0.21961],	1.5 ,	2   ,	'Bohrium'   ),
'HS':	Element([0.90196, 0.00000, 0.18039],	1.5 ,	2   ,	'Hassium'   ),
'MT':	Element([0.92157, 0.00000, 0.14902],	1.5 ,	2   ,	'Meitnerium'),
'DS':	Element([0.93725, 0.00000, 0.12157],	1.5 ,	2   ,	'Darmstadtium')
}

def load_pdb(filepath, context, atom_size, scene_scale, atom_subdivisions,
             retain_alts, multi_models, multimers):

    file = open(filepath, 'r')
    lines = file.readlines()
    file.close()

    model_list = {}
    model_flag = False
    biomolecule_flag = False
    biomolecule_list = {}
    chain_list = []
    mat_list = []

#Parse data
    
    for line in lines:
#        print(line)
        if line[:6] == 'COMPND':
            if line[11:17] == 'CHAIN:':
                s = 17
                for i in range(1, (len(line[17:]) + 1)):
                    if line[16+i:17+i] == ',':
                        chain_id = line[s:16+i].strip()
                        chain_list.append(chain_id)
                        s = 17 + i
                    elif line[16+i:17+i] == ';':
                        chain_id = line[s:16+i].strip()
                        chain_list.append(chain_id)
                        break
                    elif i == len(line[17:]):
                        chain_id = line[s:].strip()
                        chain_list.append(chain_id)
        elif line[:10] == 'REMARK 300':
            if line[11:23] == 'BIOMOLECULE:':
                biomolecule_flag = True
                s = 23
                for i in range(1, (len(line[23:]) + 1)):
                    if line[22+i:23+i] == ',':
                        bm_serial = int(line[s:22+i])
                        biomolecule_list[bm_serial] = Biomolecule(bm_serial)
                        s = 23 + i
                    elif i == len(line[23:]):
                        bm_serial = int(line[s:])
                        biomolecule_list[bm_serial] = Biomolecule(bm_serial)

        elif line[:10] == 'REMARK 350':
            if line[11:23] == 'BIOMOLECULE:':
                cur_biomolecule = biomolecule_list[int(line[23:].strip())]
            elif line[11:41] == 'APPLY THE FOLLOWING TO CHAINS:':
                s = 41
                cur_chain_list = []
                for i in range(1, (len(line[41:]) + 1)):
                    if line[40+i:41+i] == ',':
                        cur_chain_list.append(line[s:40+i].strip())
                        s = 41+i
                    elif i == len(line[41:]):
                        cur_chain_list.append(line[s:].strip())
                cur_biomolecule.chain_transforms[tuple(cur_chain_list)] = []
            elif line[13:18] == 'BIOMT':
                if line[18:19] == '1':
                    row1 = [float(line[24:33]), float(line[34:43]),
                            float(line[44:53]), float(line[60:68])]
                elif line[18:19] == '2':
                    row2 =[float(line[24:33]), float(line[34:43]),
                            float(line[44:53]), float(line[60:68])]
                elif line[18:19] == '3':
                    row3 = [float(line[24:33]), float(line[34:43]),
                            float(line[44:53]), float(line[60:68])]
                    cur_biomolecule.chain_transforms[tuple(cur_chain_list)].append([row1, row2, row3])
                    
                        
        elif line[:5] == 'MODEL':
            model_id = int(line[10:14])
            model_list[model_id] = Model(model_id)
            cur_model = model_list[model_id]
            model_flag = True
            for chain in chain_list:
                cur_model.chains[chain] = Chain(chain)
        elif line[:6] == 'ENDMDL':
            cur_model = None
        elif line[:4] == 'ATOM':
            if not model_flag:
                model_list[1] = Model(1)
                cur_model = model_list[1]
                model_flag = True
                for chain in chain_list:
                    cur_model.chains[chain] = Chain(chain)

            serial = int(line[6:11])
            name = line[12:16].strip()
            altloc = line[16:17]
            resname = line[17:20]
            chainid = line[21:22]
            resseq = int(line[22:26])
            icode = line[26:28].strip()
            x = float(line[30:38]) * scene_scale
            y = float(line[38:46]) * scene_scale
            z = float(line[46:54]) * scene_scale
            occupancy = float(line[54:60])
            tempfactor = float(line[60:66])
            element = line[76:78].strip()
            charge = line[78:80].strip()
            '''print('******************************************************************')
            print('serial       : ' )
            print(serial) 
            print('name         : ' ) 
            print(name) 
            print('altloc       : ' ) 
            print(altloc) 
            print('resname      : ' ) 
            print(resname) 
            print('chainid      : ' )
            print(chainid) 
            print('resseq       : ' )
            print(resseq) 
            print('icode        : ' )
            print(icode) 
            print('x            : ' )
            print(x) 
            print('y            : ' )
            print(y) 
            print('z            : ' )
            print(z) 
            print('occupancy    : ' )
            print(occupancy) 
            print('tempfactor   : ' )
            print(tempfactor) 
            print('element      : ' )
            print(element) 
            print('charge       : ' )
            print(charge) 
            print('******************************************************************')'''
            cur_model.chains[chainid].atoms[serial] = Atom(serial, name, altloc,
                                                           resname, chainid,
                                                           resseq, icode,
                                                           x, y, z, occupancy,
                                                           tempfactor, element,
                                                           charge)
    

    if (not multimers) or (not biomolecule_flag):
        #Create a default biomolecule w/ all chains and identity transform
        #Overwrites original biomolecule_list
        biomolecule_flag = True
        biomolecule_list = {1:Biomolecule(1)}
        biomolecule_list[1].chain_transforms[tuple(chain_list)] = []
        biomolecule_list[1].chain_transforms[tuple(chain_list)].append([[1, 0, 0, 0],
                                                                        [0, 1, 0, 0],
                                                                        [0, 0, 1, 0]])
        
#Create atom mesh template
    bpy.ops.mesh.primitive_ico_sphere_add(subdivisions=atom_subdivisions,
                                          size=(atom_size * scene_scale))
    bpy.ops.object.shade_smooth()
    atom_mesh = bpy.context.active_object.data
    atom_mesh.name = 'Atom_Template'
    bpy.ops.object.delete()

    layers = bpy.context.scene.layers

#After parsing and preparing the templates, generate the output
    for model_id, model in model_list.items():
        if (not multi_models) and model_id != 1:
            break

        for bm_serial, biomolecule in biomolecule_list.items():
            biom_mesh = bpy.data.meshes.new('Biomolecule' + str(bm_serial) + '.' + 
                                        str(model_id))
            cur_biom = bpy.data.objects.new('Biomolecule' + str(bm_serial) +
                                               '.' + str(model_id), biom_mesh)
            bpy.context.scene.objects.link(cur_biom)
        
            for chain_clones, transforms in biomolecule.chain_transforms.items():
                for chain in chain_clones:

                    for transform in transforms:
                        #rotations
                        row1 = transform[0][0:3]
                        row2 = transform[1][0:3]
                        row3 = transform[2][0:3]
                        #translations
                        dx = transform[0][3]
                        dy = transform[1][3]
                        dz = transform[2][3]

                        for serial, atom in model.chains[chain].atoms.items():
                            #Prunes alternative locations for the atoms
                            #(should pick the one with highest occupancy but doesn't)
                            if (atom.altloc == ' ' or atom.altloc == 'A') or retain_alts:

                                element = atom_data[atom.element].name

                                #Generate master element models
                                if element not in mat_list:

                                    #Create a master atom
                                    mesh = atom_mesh.copy()
                                    mesh.name = element
                                    mat = bpy.data.materials.new(element)
                                    mat.diffuse_color = atom_data[atom.element].color
                                    mesh.materials.append(mat)
                                    master_atom = bpy.data.objects.new(element, mesh)
                                    master_atom.scale = [atom_data[atom.element].vdw_radius]*3
                                    master_atom.layers = layers
                                    master_atom.name = element
                                    bpy.context.scene.objects.link(master_atom)

                                    mat_list.append(element)
                                else:
                                    pass

                                #Generate element vertex groups
                                if element not in cur_biom.vertex_groups:
                                    cur_vert_group = cur_biom.vertex_groups.new(element) 
                                    #Adds a key in the vert_group_count
                                    biomolecule.vert_group_counts[cur_vert_group] = 0
                    
                                else:
                                    cur_vert_group = cur_biom.vertex_groups[element]

                #Generate particle systems (can be merged with vertex group generator)
                                if element not in cur_biom.particle_systems:
                                    bpy.context.scene.objects.active = cur_biom
                                    bpy.ops.object.particle_system_add()
                                    cur_particle = cur_biom.particle_systems.active
                                    cur_particle.name = element
                                    cur_particle.settings.name = (element + '.' + str(bm_serial) + '.' + str(model_id))
                                    cur_particle.settings.frame_start = 0
                                    cur_particle.settings.frame_end = 0
                                    cur_particle.settings.lifetime = 10000
                                    cur_particle.settings.emit_from = 'VERT'
                                    cur_particle.settings.use_emit_random = False
                                    cur_particle.settings.normal_factor = 0
                                    cur_particle.settings.particle_size = 1
                                    cur_particle.settings.render_type = 'OBJECT' 
                                    cur_particle.settings.dupli_object = bpy.data.objects[element]
                                    cur_particle.settings.effector_weights.gravity = 0
                                    cur_particle.vertex_group_density = element

                                biomolecule.vert_group_index[biomolecule.atom_count] = cur_vert_group
                                biomolecule.vert_group_counts[cur_vert_group] += 1
                                biomolecule.atom_count += 1
                                tx = atom.x * row1[0] + atom.y * row1[1] + atom.z * row1[2] + (dx * scene_scale)
                                ty = atom.x * row2[0] + atom.y * row2[1] + atom.z * row2[2] + (dy * scene_scale)
                                tz = atom.x * row3[0] + atom.y * row3[1] + atom.z * row3[2] + (dz * scene_scale)
                                biomolecule.vert_list.extend([tx, ty, tz])
                            else:
                                pass

            biom_mesh.vertices.add(biomolecule.atom_count)
            biom_mesh.vertices.foreach_set('co', biomolecule.vert_list)

            for vert_index, vert_group in biomolecule.vert_group_index.items():
                aa = []  # neeed array to vertex_groups.assign
                aa.append(vert_index)
                vert_group.add(aa, 1, "ADD")

            for vert_group, count in biomolecule.vert_group_counts.items():
                bpy.data.particles[vert_group.name + '.' + str(bm_serial) + '.' + str(model_id)].count = count