Fig. 3.

Gene and protein structures of GSTT enzymes. (A) Schematic representation of selected chimeric genes. Sequences inherited from hGSTT1-1 are shown as red bars, and segments from rGSTT2-2 are shown as blue bars. Insertions not derived from either parent are represented as green bars. Positioning of the progeny segments corresponds to their origin in the parental genes (depicted at top). Point mutations are represented as white (silent) or green (encoding for amino acid substitution) stars. Sequences encoding the G and H sites are noted. (B) Mapping of SCR9 amino acid sequence onto the crystal structure of the hGSTT2 monomer. Human-derived sequence is in red, rat sequence is in blue, and identical amino acids at fusion points are in magenta. The location of the active site is marked with a black star. (C) Mapping of SCR23 amino acid sequence onto the hGSTT2 structure. Point mutations are shown in green.