diff --git a/gget/gget_setup.py b/gget/gget_setup.py
index 5f6c57b9..860a44de 100644
--- a/gget/gget_setup.py
+++ b/gget/gget_setup.py
@@ -246,7 +246,7 @@ def setup(module):
                 # Install pdbfixer version compatible with openmm v7.5.1
                 PDBFIXER_VERSION = "v1.7"
         except:
-            PDBFIXER_VERSION = "main"
+            PDBFIXER_VERSION = "1.8.1" # Latest: 1.9
 
         command = f"""
             git clone -q --branch {PDBFIXER_VERSION} {PDBFIXER_GIT_REPO} {pdbfixer_folder} \
diff --git a/tests/test_cellxgene.py b/tests/test_cellxgene.py
index d76df5d2..4b741013 100644
--- a/tests/test_cellxgene.py
+++ b/tests/test_cellxgene.py
@@ -2,10 +2,7 @@
 import pandas as pd
 import json
 from gget.gget_cellxgene import cellxgene
-
-# Install cellxgene module specific dependencies
 from gget.gget_setup import setup
-setup("cellxgene")
 
 # Load dictionary containing arguments and expected results
 with open("./tests/fixtures/test_cellxgene.json") as json_file:
@@ -40,6 +37,9 @@ def repr_dict(adata):
 
 
 class TestCellxgene(unittest.TestCase):
+    def install_dependencies(self):
+        setup("cellxgene")
+
     def test_cellxgene_adata(self):
         test = "test1"
         expected_result = cellxgene_dict[test]["expected_result"]
diff --git a/tests/test_gpt.py b/tests/test_gpt.py
index 0bd48d0e..99c37d40 100644
--- a/tests/test_gpt.py
+++ b/tests/test_gpt.py
@@ -1,13 +1,13 @@
 import unittest
 from unittest.mock import patch
 from gget.gget_gpt import gpt
-
-# Install gpt module specific dependencies
 from gget.gget_setup import setup
-setup("gpt")
 
 
 class TestGpt(unittest.TestCase):
+    def install_dependencies(self):
+        setup("gpt")
+
     @patch("openai.ChatCompletion.create")
     def test_gpt(self, mock_create):
         # Mock the response from the API