diff --git a/modelseedpy/__init__.py b/modelseedpy/__init__.py
index 995c054..2c4e20b 100644
--- a/modelseedpy/__init__.py
+++ b/modelseedpy/__init__.py
@@ -14,7 +14,7 @@
 
 __author__ = "Christopher Henry"
 __email__ = "chenry@anl.gov"
-__version__ = "0.4.0"
+__version__ = "0.4.2"
 
 logger = logging.getLogger(__name__)
 
diff --git a/modelseedpy/core/mstemplate.py b/modelseedpy/core/mstemplate.py
index cffc610..5cce592 100644
--- a/modelseedpy/core/mstemplate.py
+++ b/modelseedpy/core/mstemplate.py
@@ -523,16 +523,16 @@ def __init__(
         biomass_id: str,
         name: str,
         type: str,
-        dna: float,
-        rna: float,
-        protein: float,
-        lipid: float,
-        cellwall: float,
-        cofactor: float,
-        pigment: float,
-        carbohydrate: float,
-        energy: float,
-        other: float,
+        dna: float = 0,
+        rna: float = 0,
+        protein: float = 0,
+        lipid: float = 0,
+        cellwall: float = 0,
+        cofactor: float = 0,
+        pigment: float = 0,
+        carbohydrate: float = 0,
+        energy: float = 0,
+        other: float = 0,
     ):
         """
 
diff --git a/setup.py b/setup.py
index 17f6e13..3c27af1 100644
--- a/setup.py
+++ b/setup.py
@@ -10,7 +10,7 @@
 
 setup(
     name="ModelSEEDpy",
-    version="0.4.0",
+    version="0.4.2",
     description="Python package for building and analyzing models using ModelSEED",
     long_description_content_type="text/x-rst",
     long_description=readme,