diff --git a/Tests/runtest.py b/Tests/runtest.py
index 8f7710e..d82c7c4 100755
--- a/Tests/runtest.py
+++ b/Tests/runtest.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python3
+#!/usr/bin/env python
 
 """ Run test for test pdbs """
 
diff --git a/propka.py b/propka.py
index a789017..f26bc53 100755
--- a/propka.py
+++ b/propka.py
@@ -1,4 +1,4 @@
-#!/usr/bin/python3
+#!/usr/bin/env python
 
 import string,re,sys,os,math
 import Source.lib, Source.molecular_container