diff --git a/glycoshield/lib.py b/glycoshield/lib.py
index 512ab710006faf4b9da33314f7ac0284fd8d7a7c..8f74353c6533553ea6c5280d2a5733a8cfeba333 100644
--- a/glycoshield/lib.py
+++ b/glycoshield/lib.py
@@ -132,13 +132,13 @@ class glycoshield:
                 if self.initialsugarframes[isugar] == 0:
                     self.initialsugarframes[isugar] = self.usugar.trajectory.n_frames
                 # select (part of) the protein that is connected to the sugar
-                tripep = self.usugar.select_atoms('protein and resid {} and name N CA C O'.format(" ".join([str(i) for i in resids_on_sugar])))
+                tripep = self.usugar.select_atoms('protein and resid {} and name in N CA C O OT1'.format(" ".join([str(i) for i in resids_on_sugar])))
 
                 # Test whether sequon is in the 2:N-1 range:
                 self._test_sequon(resids_on_protein, protchain)
 
                 # select sequon on protein
-                sequon = self.uprot.select_atoms('segid {} and resid {} and name N CA C O'.format(protchain, " ".join([str(i) for i in resids_on_protein])))
+                sequon = self.uprot.select_atoms('segid {} and resid {} and name in N CA C O OT1'.format(protchain, " ".join([str(i) for i in resids_on_protein])))
 
                 # the selection has to have same length for protein and peptide with the sugar!
                 # Now select part of the peptide that should be transplanted onto protein. By default we do not transplant the part which gets selected.