diff --git a/prody/trajectory/trajbase.py b/prody/trajectory/trajbase.py
index 2db0cca74..56c0248d0 100644
--- a/prody/trajectory/trajbase.py
+++ b/prody/trajectory/trajbase.py
@@ -2,7 +2,7 @@
 """This module defines base class for trajectory handling."""
 
 from numbers import Integral
-from numpy import ndarray, unique
+from numpy import ndarray, unique, array
 
 from prody.ensemble import Ensemble
 from prody.utilities import checkCoords, checkWeights
@@ -370,7 +370,7 @@ def hasUnitcell(self):
         pass
 
 
-    def wrap(self, unitcell=None, center=np.array([0., 0., 0.])):
+    def wrap(self, unitcell=None, center=array([0., 0., 0.])):
         """Wrap atoms into an image of the system simulated under periodic boundary
         conditions for all frames and returns a new Trajectory.