diff --git a/modules/mol/base/src/impl/chain_impl.cc b/modules/mol/base/src/impl/chain_impl.cc
index 8b3cbe271eef0e860d78ea5039ac7f00a35e191e..42f24164e282d6cd2c183cbe841a01a4b5ecc44e 100644
--- a/modules/mol/base/src/impl/chain_impl.cc
+++ b/modules/mol/base/src/impl/chain_impl.cc
@@ -69,6 +69,7 @@ ResidueImplPtr ChainImpl::AppendResidue(const ResidueImplPtr& res, bool deep)
   dst_res->SetSecStructure(res->GetSecStructure());
   dst_res->SetChemClass(res->GetChemClass());  
   dst_res->SetProtein(res->IsProtein());
+  dst_res->SetChemType(res->GetChemType());
   dst_res->SetIsLigand(res->IsLigand());
   if(deep)
   {