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9.B.395.  The Uncharacterized Prokaryotic Membrane Protein (UPMP) Family

Members of the UPMP family are integral membrane proteins with 6 or 7 TMSs in a 5+ 1 or 6 + 1 topology, where the N-terminal TMSs are present in a cluster, followed by a hydrophilic region and then a C-terminal TMS.  Most protein homologs in the NCBI database are referred to as "hypothetical proteins".