Figure 2.
Figure 2. The structure of E. coli MTHFR. a, A view along the
axis of the [8]
[8]
barrel looking toward the C-terminal ends of the −strands^37.
FAD is drawn in ball-and-stick mode. Helix 5,
which precedes the site corresponding to the human A arrow
V polymorphism, is colored red in this and succeeding figures.
b, A view perpendicular to the barrel axis and toward the si
face of the flavin ring, showing the truncation of strand 8
and helix 8
and the resulting groove in which methylenetetrahydrofolate is
expected to bind. Ala 177, the site of the Ala arrow
Val mutation, is drawn with gray dot surfaces, and is at the
rear of the barrel. c, A stereo drawing of the chain fold from
approximately the same perspective as in ( a).
The above figure is reprinted
by permission from Macmillan Publishers Ltd:
Nat Struct Biol
(1999,
6,
359-365)
copyright 1999.
[8]
[8]
barrel looking toward the C-terminal ends of the 
arrow
V polymorphism, is colored red in this and succeeding figures.
b, A view perpendicular to the barrel axis and toward the si
face of the flavin ring, showing the truncation of strand