Chemistry Reference
In-Depth Information
FIGURE 13.18
Role of clusters in substrate binding
e
in aconitase the cluster geometry shifts from four- to six-coordination on substrate
binding. The coordinating iron atom abstracts the hydroxide anion during dehydration.
(Adapted from
Voet & Voet, 2004
.
)
FIGURE 13.19
S-adenosylmethionine (SAM) is a source of 5-deoxyadenosyl radicals. SAM binds to the subsite iron (in blue) of the reduced
[4Fe
e
4S] cluster via its
a
-aminocarboxylate group. The 5-deoxyadenosine radical is then formed by electron transfer with release of
methionine.
(From
Fontecave, Atta, & Mulliez, 2004
. Copyright 2004 with permission from Elsevier.)
