Passing lists to serialize and deserialize methods for XML parsing

In cSharp I am trying to make this code more generic.

    string SerializeObject(object pObject)
 {
     string XmlizedString = null;
     MemoryStream memoryStream = new MemoryStream();
     XmlSerializer xs = new XmlSerializer(typeof(List<SaveStructure.GameItems>));
     XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8);
     xs.Serialize(xmlTextWriter, pObject);
     memoryStream = (MemoryStream)xmlTextWriter.BaseStream;
     XmlizedString = UTF8ByteArrayToString(memoryStream.ToArray());
     return XmlizedString;
 }

 object DeserializeObject(string pXmlizedString)
 {
     XmlSerializer xs = new XmlSerializer(typeof(List<SaveStructure.GameItems>));
     MemoryStream memoryStream = new MemoryStream(StringToUTF8ByteArray(pXmlizedString));
     return xs.Deserialize(memoryStream);
 }

This is what I have done so far :

 string SerializeObject(object pObject, List<string> x)
 {
     string XmlizedString = null;
     MemoryStream memoryStream = new MemoryStream();
     XmlSerializer xs = new XmlSerializer(typeof(List<x>));
     XmlTextWriter xmlTextWriter = new XmlTextWriter(memoryStream, Encoding.UTF8);
     xs.Serialize(xmlTextWriter, pObject);
     memoryStream = (MemoryStream)xmlTextWriter.BaseStream;
     XmlizedString = UTF8ByteArrayToString(memoryStream.ToArray());
     return XmlizedString;
 }

 object DeserializeObject(string pXmlizedString, List<string> x)
 {
     XmlSerializer xs = new XmlSerializer(typeof(List<x>));
     MemoryStream memoryStream = new MemoryStream(StringToUTF8ByteArray(pXmlizedString));
     return xs.Deserialize(memoryStream);
 }

This is how I am calling it :

 string _data = string.Empty;
 _data = SerializeObject(_GameItems, List<SaveStructure.GameItems>);

But it isn't working I'm getting errors like this

expression denotes a type', where a variable', value' or method group' was expected Argument #2' cannot convert object' expression to type System.Collections.Generic.List<string>' > Argument #1' cannot convert System.Collections.Generic.List<string>' expression to type System.Type'

How do I rewrite this code in cSharp so I can pass any type of List to work with the methods SerializeObject and DeserializeObject ?