TY  - JOUR
PY  - 2009//
TI  - Non-zinc mediated inhibition of carbonic anhydrases: coumarins are a new class of suicide inhibitors
JO  - Journal of the American Chemical Society
A1  - Maresca, Alfonso
A1  - Temperini, Claudia
A1  - Vu, Hoan
A1  - Pham, Ngoc B.
A1  - Poulsen, Sally-Ann
A1  - Scozzafava, Andrea
A1  - Quinn, Ronald J.
A1  - Supuran, Claudiu T.
SP  - 3057
EP  - 3062
VL  - 131
IS  - 8
N2  - The X-ray crystal structure of the adduct between the zinc metalloenzyme carbonic anhydrase II (CA, EC 4.2.1.1) with the recently discovered natural product coumarin derivative 6-(1S-hydroxy-3-methylbutyl)-7-methoxy-2H-chromen-2-one showed the coumarin hydrolysis product, a cis-2-hydroxy-cinnamic acid derivative, and not the parent coumarin, bound within the enzyme active site. The bound inhibitor exhibits an extended, two-arm conformation that effectively plugs the entrance to the enzyme active site with no interactions with the catalytically crucial zinc ion. The inhibitor is sandwiched between Phe131, with which it makes an edge-to-face stacking, and Asn67/Glu238sym, with which it makes several polar and hydrogen bonding interactions. This unusual binding mode, with no interactions between the inhibitor molecule and the active site metal ion is previously unobserved for this enzyme class and presents a new opportunity for future drug design campaigns to target a mode of inhibition that differs substantially from classical inhibitors such as the clinically used sulfonamides and sulfamates. Several structurally simple coumarin scaffolds were also shown to inhibit all 13 catalytically active mammalian CA isoforms, with inhibition constants ranging from nanomolar to millimolar. The inhibition is time dependent, with maximum inhibition being observed after 6 h.<p /> <p>Language: en</p>
LA  - en
SN  - 0002-7863
UR  - http://dx.doi.org/10.1021/ja809683v
ID  - ref1
ER  -