Fig. 1. The AAM-B constructs used in this study and alignment of the N-terminal hydrophobic regions of AAM-B, ALDI, CYB5R3 and CYP2C9. (A) Wild-type AAM-B (WT) has four domains: an N-terminal hydrophobic region, a putative juxtamembrane domain, a putative methyltransferase domain and a C-terminal region that lacks any distinguishing features. Deletions made in the various regions as well as three chimeric proteins used in this study are shown. Each diagram represents a single construct, with the exception of AS1-7, which is a summary of seven constructs: the seven numbered boxes represent the regions mutated to alanines in the corresponding seven constructs. (B) Alignment of the first 23-28 amino acids of AAM-B, its close homolog ALDI, CYB5R3 and the p450 family member CYP2C9. Shaded boxes highlight hydrophobic residues (amino acid value>0 on the Kyte-Doolittle scale). Acidic residues are in red, basic residues in blue and prolines are highlighted yellow.