diff --git a/tests/model/test_ontology_annotation.py b/tests/model/test_ontology_annotation.py
index c087f32f..b7e18ad7 100644
--- a/tests/model/test_ontology_annotation.py
+++ b/tests/model/test_ontology_annotation.py
@@ -55,7 +55,7 @@ def test_setters(self):
 
     def test_builtins(self):
         expected_str = ("isatools.model.OntologyAnnotation(term='test_term', "
-                        "term_source=isatools.model.OntologySource(name='test_term_source',"
+                        "term_source=isatools.model.OntologySource(name='test_term_source', "
                         "file='', version='', description='', comments=[]), "
                         "term_accession='test_term_accession', "
                         "comments=[])")