Browse Source

Add bends discovery from position vectors

Thomas Forest 5 years ago
parent
commit
45f0eb8c93
3 changed files with 109 additions and 14 deletions
  1. 2 1
      src/atom.py
  2. 4 2
      src/dssp.py
  3. 103 11
      src/structure.py

+ 2 - 1
src/atom.py View File

@@ -16,7 +16,8 @@ class Atom:
16 16
         self.res_seq_nb = res_seq_nb
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         self.coord_x = coordinates[0]
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         self.coord_y = coordinates[1]
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-        self.coord_z = coordinates[2]             
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+        self.coord_z = coordinates[2]
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+        self.coords = coordinates
20 21
 
21 22
 class Residue:
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     def __init__(self, atoms_list):

+ 4 - 2
src/dssp.py View File

@@ -14,5 +14,7 @@ else:
14 14
     #print(pdb_file.residues[2].h_bond(pdb_file.residues[40]))
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     #print(get_turns(pdb_file.residues))
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     #print(pdb_file.residues[27].h_bond(pdb_file.residues[28]))
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-    print(get_bridges(pdb_file.residues))
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-
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+    #print(get_bridges(pdb_file.residues))
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+    turns = get_turns(pdb_file.residues)
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+    get_helix(pdb_file.residues, turns)
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+    get_bends(pdb_file.residues)

+ 103 - 11
src/structure.py View File

@@ -1,27 +1,37 @@
1
+import math
1 2
 
2
-class Turn:
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+class Structure:
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+    def __init__(self, res):
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+        self.res = res
3 6
 
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-    def __init__(self, turn_type, res_num):
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+class Turn(Structure):
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+
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+    def __init__(self, turn_type, res):
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         self.turn_type = turn_type
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+        Structure.res = res
6 12
                         
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-class Bridge:
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+class Bridge(Structure):
8 14
 
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     def __init__(self, bridge_type, res_num):
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         self.bridge_type = bridge_type
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         self.res_num = res_num
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+        Structure.res = res_num
12 19
 
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-class Helix:
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+class Helix(Structure):
14 21
 
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-    def __init__(self, residues):
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+    def __init__(self, residues, res_num):
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         self.residues = residues
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+        self.res_num = res_num
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+        Structure.res = res_num
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18 27
 def get_turns(residues):
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-    turns = []
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+    turns = {}
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     for i,res in enumerate(residues):
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         for j in range(3,6):
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             if(i+j<len(residues)):
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-                if(res.h_bond(residues[i+j]<-0.5)):
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-                    turns.append(Turn(j,i))
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+                if(res.h_bond(residues[i+j])<-0.5):
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+                    print("TURN", i+1, i+j+1)
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+                    turns[i] = Turn(j,i)
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     return(turns)
26 36
 
27 37
 def get_bridges(residues):
@@ -101,6 +111,88 @@ def get_bridges(residues):
101 111
         return(False)
102 112
 
103 113
 def get_helix(residues, turns):
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-    for i in range(residues):
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-        for j in range(i+1,i+5):
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-            if
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+    i = 1
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+    helix = []
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+    while i <= len(residues):
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+        if(i in turns.keys() and i-1 in turns.keys()):
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+            k = 0
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+            temp_res = []
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+            while(i+k in turns):
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+                k+=1
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+                temp_res.append(residues[i])
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+            if(k>2):
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+                print(k,"- HELIX at", i)
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+                helix.append(Helix(temp_res,i))
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+            i = i+k
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+        else:
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+            i+=1
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+    return(helix)
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+
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+def get_bends(residues):
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+    bends = {}
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+    for i in range(2,len(residues)-2):
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+        # print("angle",i,calculer_angles(residues[i-2].atoms["CA"].coords,
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+        #                                 residues[i].atoms["CA"].coords,
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+        #                                 residues[i+2].atoms["CA"].coords))
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+        
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+        angle = vector_angles(vectors_substr(position_vector(residues[i].atoms["CA"].coords),
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+                                             position_vector(residues[i-2].atoms["CA"].coords)),
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+                              vectors_substr(position_vector(residues[i+2].atoms["CA"].coords),
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+                                             position_vector(residues[i].atoms["CA"].coords)))
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+        if(angle>70):
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+            print("angle", i+1, angle)
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+    return(bends)
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+
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+def vecteur_deux_points (a, b):
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+    xAB = b[0]-a[0]
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+    yAB = b[1]-a[1]
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+    zAB = b[2]-a[2]
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+    coord_AB = [xAB,yAB,zAB]
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+    return coord_AB
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+
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+def produit_scalaire (a, b, c):
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+    coord_BA = vecteur_deux_points(b, a)
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+    coord_BC = vecteur_deux_points(b, c)
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+    dot_product = coord_BA[0]*coord_BC[0] + coord_BA[1]*coord_BC[1] + coord_BA[2]*coord_BC[2]
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+    return dot_product
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+
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+
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+def norme_vecteur (a,b):
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+    vecteur = vecteur_deux_points(a,b)
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+    norme = math.sqrt(vecteur[0]**2 + vecteur[1]**2 + vecteur[2]**2)
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+    return norme
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+
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+def vector_norm(v):
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+    norm = math.sqrt(v[0]**2 + v[1]**2 + v[2]**2)
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+    return norm
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+
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+def dot_product(v1,v2):
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+    dot_product = v1[0]*v2[0] + v1[1]*v2[1] + v1[2]*v2[2]
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+    return(dot_product)
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+
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+def position_vector(c):
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+    vector = vecteur_deux_points([0,0,0],c)
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+    return vector
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+
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+def vectors_substr(v1, v2):
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+    return ([v2[0]-v1[0],
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+             v2[1]-v1[1],
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+             v2[2]-v1[2]])
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+
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+def vector_angles(v1,v2):
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+    dot_prod = dot_product(v1,v2)
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+    norm_v1 = vector_norm(v1)
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+    norm_v2 = vector_norm(v2)
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+    term = dot_prod/(abs(norm_v1)*abs(norm_v2))
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+    rad_angle = math.acos(term)
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+    deg_angle = rad_angle*(180/math.pi)
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+    return deg_angle
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+
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+def calculer_angles (a,b,c):
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+    dot_product_ABC = produit_scalaire(a,b,c)
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+    norme_BA = norme_vecteur (b,a)
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+    norme_BC = norme_vecteur (b,c)
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+    terme = dot_product_ABC/(abs(norme_BA)*abs(norme_BC))
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+    angle_radian = math.acos(terme)
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+    angle_degre = angle_radian*(180/math.pi)
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+    return angle_degre