COVALENT CHROMATOGRAPHY OF INFLUENZA-VIRUS MEMBRANE M1 PROTEIN ON ACTIVATED THIOPROPYL SEPHAROSE-6B

The M1 protein of influenza virus is a highly hydrophobic polypeptide that is resistant to enzyme cleavage during incubation in water soluti ons. We show here that the M1 protein that is immobilized on an insolu ble activated support (thiopropyl Sepharose-6B) by means of a thiol-di sulfide exchange reaction acquires sensitivity to trypsin. After trypt ic digestion noncysteine-containing peptides of M1 were removed by was hing the support, while cysteine-containing ones were detached from th e support by reduction. As a result, 24 unique tryptic peptides of M1 protein were clearly separated by reversed-phase high-performance liqu id chromatography. The described method opens a new way to the investi gation of functional properties of distinct domains of viral thiol pro teins. (C) 1998 Elsevier Science B.V.