diff --git a/docs/index.rst b/docs/index.rst
index 1d39719..808ba76 100644
--- a/docs/index.rst
+++ b/docs/index.rst
@@ -308,7 +308,7 @@ This is the base type for any Entity
 	+============+==========+========================================================+============================================================================================+
 	| **Name**   | **Type** | **Attributes**                                         | **Description**                                                                            |
 	+------------+----------+--------------------------------------------------------+--------------------------------------------------------------------------------------------+
-	| @metadata  | Metadata | ``Mandatory:true`` ``ReadOnly:false`` ``NotNull:true`` | Metadata associated with the instance that is automatically created/updated by the system. |
+	| metadata  | Metadata | ``Mandatory:true`` ``ReadOnly:false`` ``NotNull:true`` | Metadata associated with the instance that is automatically created/updated by the system. |
 	+------------+----------+--------------------------------------------------------+--------------------------------------------------------------------------------------------+
 
 
diff --git a/src/main/java/org/gcube/informationsystem/base/reference/IdentifiableElement.java b/src/main/java/org/gcube/informationsystem/base/reference/IdentifiableElement.java
index 0557fbd..30638a6 100644
--- a/src/main/java/org/gcube/informationsystem/base/reference/IdentifiableElement.java
+++ b/src/main/java/org/gcube/informationsystem/base/reference/IdentifiableElement.java
@@ -12,7 +12,7 @@ import org.gcube.informationsystem.model.reference.properties.Metadata;
 public interface IdentifiableElement extends Element {
 	
 	public static final String UUID_PROPERTY = "uuid";
-	public static final String METADATA_PROPERTY = "@metadata";
+	public static final String METADATA_PROPERTY = "metadata";
 	
 	public UUID getUUID();
 
diff --git a/src/test/java/org/gcube/informationsystem/types/SerializationTest.java b/src/test/java/org/gcube/informationsystem/types/SerializationTest.java
index a2fda5c..1c2f78f 100644
--- a/src/test/java/org/gcube/informationsystem/types/SerializationTest.java
+++ b/src/test/java/org/gcube/informationsystem/types/SerializationTest.java
@@ -206,7 +206,7 @@ public class SerializationTest {
 		logger.debug("Version {}", typeVersion.toString());
 		logger.info(ElementMapper.marshal(propertyType));
 		
-		String json = "{\"@class\":\"PropertyType\",\"@metadata\":null,\"name\":\"Metadata\",\"description\":\"This class provides metadata per every IdentifiableElement\",\"superClasses\":[\"Property\"],\"properties\":[{\"@class\":\"PropertyDefinition\",\"name\":\"creationTime\",\"description\":\"Creation time. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.\",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"Date\"},{\"@class\":\"PropertyDefinition\",\"name\":\"lastUpdateTime\",\"description\":\"Last Update time. At creation time it assumes the same value of creationTime. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.\",\"mandatory\":true,\"readonly\":false,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"Date\"},{\"@class\":\"PropertyDefinition\",\"name\":\"createdBy\",\"description\":\"The user that created the Entity or the Relation. It is initialized at creation time. \",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"String\"},{\"@class\":\"PropertyDefinition\",\"name\":\"uuid\",\"description\":\"This UUID is be used to identify the Entity or the Relation univocally.\",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":\"^([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}){1}$\",\"type\":\"String\"},{\"@class\":\"PropertyDefinition\",\"name\":\"lastUpdateBy\",\"description\":\"The user that made the last update to the Entity or the Relation. At creation time, it assumes the same value of creator.\",\"mandatory\":true,\"readonly\":false,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"String\"}],\"accessType\":\"PROPERTY\",\"abstract\":false,\"version\":\"1.0.0\",\"changelog\":{\"1.0.0\":\"First Version\"}}";
+		String json = "{\"@class\":\"PropertyType\",\"metadata\":null,\"name\":\"Metadata\",\"description\":\"This class provides metadata per every IdentifiableElement\",\"superClasses\":[\"Property\"],\"properties\":[{\"@class\":\"PropertyDefinition\",\"name\":\"creationTime\",\"description\":\"Creation time. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.\",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"Date\"},{\"@class\":\"PropertyDefinition\",\"name\":\"lastUpdateTime\",\"description\":\"Last Update time. At creation time it assumes the same value of creationTime. It represents the difference, measured in milliseconds, between the creation time and midnight, January 1, 1970, UTC.\",\"mandatory\":true,\"readonly\":false,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"Date\"},{\"@class\":\"PropertyDefinition\",\"name\":\"createdBy\",\"description\":\"The user that created the Entity or the Relation. It is initialized at creation time. \",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"String\"},{\"@class\":\"PropertyDefinition\",\"name\":\"uuid\",\"description\":\"This UUID is be used to identify the Entity or the Relation univocally.\",\"mandatory\":true,\"readonly\":true,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":\"^([a-fA-F0-9]{8}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{4}-[a-fA-F0-9]{12}){1}$\",\"type\":\"String\"},{\"@class\":\"PropertyDefinition\",\"name\":\"lastUpdateBy\",\"description\":\"The user that made the last update to the Entity or the Relation. At creation time, it assumes the same value of creator.\",\"mandatory\":true,\"readonly\":false,\"notnull\":true,\"max\":null,\"min\":null,\"regexp\":null,\"type\":\"String\"}],\"accessType\":\"PROPERTY\",\"abstract\":false,\"version\":\"1.0.0\",\"changelog\":{\"1.0.0\":\"First Version\"}}";
 		logger.info(json);
 		@SuppressWarnings("unchecked")
 		PropertyType<Metadata> metadataType = (PropertyType<Metadata>) TypeMapper.deserializeTypeDefinition(json);