Collectively , these results strongly suggest that the pmrC , ugd and pmrG genes and the pbgPE operon are the only PmrA-regulated determinants required for Fe ( III ) resistance .
PmrA-regulated genes described and the modifications their products mediate are : pmrHFIJKL/pmrE , 4-aminoarabinose ; cptA , heptose I phosphoethanolamine phosphotransferase ; pmrC , lipid-A phosphoethanolamine phosphotransferase ; cld , O-antigen chain length determinant ; pmrG , heptose II phosphatase .