Salt-induced Changes in the Plasma Membrane Proteome of the Halotolerant Alga

The halotolerant alga Dunaliella salina is a recognized model photosynthetic organism for studying plant adap-tation to high salinity. The adaptation mechanisms involve major changes in the proteome composition associated with energy metabolism and carbon and iron acquisition. To clarify the molecular basis for the remarkable resist-ance to high salt, we performed a comprehensive pro-teomics analysis of the plasma membrane. Plasma mem-brane proteins were recognized by tagging intact cells with a membrane-impermeable biotin derivative. Proteins were resolved by two-dimensional blue native/SDS-PAGE and identified by nano-LC-MS/MS. Of 55 identified pro-teins, about 60 % were integral membrane or membrane-associated proteins. We identified novel surface coat pro-teins, lipid-metabolizing enzymes, a new family o