FIG 8.

Dendrogram and properties of related substrate binding proteins. Substrate binding proteins (GenBank accession numbers are indicated) were aligned using ClustalO (77) and the resultant dendrogram drawn using MSwordtree (97). Proteins in bold are derived from Gram-negative organisms. Published metal binding properties with relative binding affinities if known, experimentally established metal transport, regulation in response to the indicated metal ion(s), and the presence (Y) or absence (N) of a His-rich region (His-R) are indicated (15, 23, 26, 27, 31–34, 78–96). —, information not available. *, activation by the indicated metal.