1 files changed, 38 insertions, 0 deletions
diff --git a/plip/test/test_hydrogen_bonds.py b/plip/test/test_hydrogen_bonds.py
new file mode 100644
index 0000000..9d68532
--- /dev/null
+++ b/plip/test/test_hydrogen_bonds.py
@@ -0,0 +1,38 @@
+import unittest
+
+from plip.basic import config
+from plip.structure.preparation import PDBComplex, PLInteraction
+
+
+def characterize_complex(pdb_file: str, binding_site_id: str) -> PLInteraction:
+    pdb_complex = PDBComplex()
+    pdb_complex.load_pdb(pdb_file)
+    for ligand in pdb_complex.ligands:
+        if ':'.join([ligand.hetid, ligand.chain, str(ligand.position)]) == binding_site_id:
+            pdb_complex.characterize_complex(ligand)
+    return pdb_complex.interaction_sets[binding_site_id]
+
+
+class HydrogenBondTestCase(unittest.TestCase):
+
+    def test_4dst_nondeterministic_protonation(self):
+        config.NOHYDRO = False
+        for i in range(0, 10):
+            interactions = characterize_complex('./pdb/4dst.pdb', 'GCP:A:202')
+            all_hbonds = interactions.hbonds_ldon + interactions.hbonds_pdon
+            self.assertTrue(len(all_hbonds) == 16 or len(all_hbonds) == 17)
+
+    def test_4dst_deterministic_protonation(self):
+        config.NOHYDRO = True
+        for i in range(0, 10):
+            interactions = characterize_complex('./pdb/4dst_protonated.pdb', 'GCP:A:202')
+            all_hbonds = interactions.hbonds_ldon + interactions.hbonds_pdon
+            self.assertTrue(len(all_hbonds) == 16)
+
+    def test_no_protonation(self):
+        config.NOHYDRO = True
+        interactions1 = characterize_complex('./pdb/1x0n_state_1.pdb', 'DTF:A:174')
+        self.assertEqual(len(interactions1.hbonds_ldon), 0)
+        config.NOHYDRO = False
+        interactions2 = characterize_complex('./pdb/1x0n_state_1.pdb', 'DTF:A:174')
+        self.assertEqual(len(interactions2.hbonds_ldon), 1)