Figure 6.

Amino acids at one of the interfaces of the large and small subunits. The region shown involves residues of helix 8 of the C-terminal domain of the large subunit (Knight et al., 1990) and the N-terminal segment of the small subunit. The side chains of amino acids that differ between the two species, or are adjacent to sequence changes that make contacts at the subunit interface (Fig. 2), are shown in this Molscript (Kraulis, 1991) rendition of tobacco Rubisco (Curmi et al., 1992). The position of the N-terminal end of helix 8 is critical for ribulose-P₂ binding at the active site. L-subunit, Large subunit; S-subunit, small subunit.