Membrane's Eleven: heavy-atom derivatives of membrane-protein crystals

A database has been assembled of heavy- atom derivatives used in the structure determination of membrane proteins. The database can serve as a guide to the design of experiments in the search for heavy- atom derivatives of new membrane-protein crystals. The database pinpoints organomercurials, platinum( II) and trimethyllead compounds as being particularly useful. On the other hand, lanthanide and uranyl compounds are poorly represented, which may be a consequence of these compounds having aggressive effects in crystal- soaking procedures. Furthermore, the database highlights the variety of methods applied in the preparation of heavy- atom- derivatized crystals and in phasing. Cocrystallization can be further exploited. Phases have predominantly been obtained by SIRAS/ MIRAS methods rather than SAD/ MAD in recent structure determinations.