FIG. 2.

Comparison of the amino acid sequences of the S. meliloti Hut-component transport system with those of glycine betaine uptake systems of B. subtilis OpuA and OpuC (accession numbers U17292 and AF009352, respectively), E. coli ProU (accession number M24856), and E. coli histidine transport system His (accession numbers U47027 and Y00455). (A) Alignment of ATPases ProV from E. coli and OpuAA and OpuCA from B. subtilis and comparison with the S. meliloti HutV and E. coli HisP proteins. The numbers above the alignment correspond to the amino acid residue position of OpuAA. The Walker A and B ATP binding sites and the ABC transporter family signatures are boxed. Amino acids chosen for the synthesis of PCR primers (bup1 and bup2) are underlined. (B) Partial alignment of S. meliloti HutW with the membrane integral proteins from B. subtilis (BsOpuAB, BsOpuCB, and BsOpuCD), and from E. coli (EcProW, EcHisM, and EcHisQ). The EAA loop is indicated. The alignments were made with the Clustal program from the GCG.