, default 'display')
                   - 'display' displays all found multiplicities
                   - 'ignore'  ignore multiplicities and use the protein
                               with the lowest index in the database.
                   - 'add'     adds all the multiple proteins as
                               isozymes for the given reaction
   modelAdapter    a loaded model adapter (Optional, will otherwise use the
                   default model adapter).

 Output:
   model           ecModel