A new protein of unknown structure has been purified. Gel filtration chromatography reveals that the native protein has a molecular weight of 240,000. Chromatography in the presence of 6 M guanidine hydrochloride yields only a peak for a protein of Mr 60,000. Chromatography in the presence of 6 M guanidine hydrochloride and 10mM 2-mercaptoethanol yields peaks of Mr 34000 and 26000. Explain what can be determined about the structure of this protein from this data.