PDBsum entry 1jv0

Go to PDB code: 
Top Page protein ligands metals links
Lyase PDB id
Protein chains
257 a.a. *
EDO ×2
_ZN ×6
_CL ×3
Waters ×440
* Residue conservation analysis

References listed in PDB file
Key reference
Title Crystal structure of a zinc-Activated variant of human carbonic anhydrase i, Ca i michigan 1: evidence for a second zinc binding site involving arginine coordination.
Authors M.Ferraroni, S.Tilli, F.Briganti, W.R.Chegwidden, C.T.Supuran, K.E.Wiebauer, R.E.Tashian, A.Scozzafava.
Ref. Biochemistry, 2002, 41, 6237-6244. [DOI no: 10.1021/bi0120446]
PubMed id 12009884
The human genetic variant carbonic anhydrase I (CA I) Michigan 1 results from a single point mutation that changes His 67 to Arg in a critical region of the active site. This variant of the zinc metalloenzyme appears to be unique in that it possesses an esterase activity that is specifically enhanced by added free zinc ions. We have determined the three-dimensional structure of human CA I Michigan 1 by X-ray crystallography to a resolution of 2.6 A. In the absence of added zinc ions, the mutated residue, Arg 67, points out of the active site, hydrogen bonding with the carboxylate of Asn 69. This contrasts with the orientation of His 67, in the native isozyme, which points into the active site. The orientations of His 94, His 96, and His 119, that coordinate the catalytic zinc ion, and of the catalytically critical Thr 199-Glu 106 hydrogen bonding system, are largely unchanged in the mutant. The structure of an enzyme adduct with a second zinc bound was determined to a resolution of 2.0 A. The second zinc ion is coordinated to His 64, His 200, and Arg 67. This arginine residue reverses its orientation on zinc binding and turns into the active site. The residues at these three positions have been implicated in determining the specific kinetic properties of native CA I. This is, to our knowledge, the first example of a zinc ion coordinating with an arginine residue in a Zn(II) enzyme.
Secondary reference #1
Title New genetically determined molecular form of erythrocyte esterase in man.
Authors C.R.Shaw, F.N.Syner, R.E.Tashian.
Ref. Science, 1962, 138, 31-32.
PubMed id 13911449
Secondary reference #2
Title Marked zinc activation of ester hydrolysis by a mutation, 67-His (cat) to arg (cgt), In the active site of human carbonic anhydrase i.
Authors W.R.Chegwidden, L.E.Wagner, P.J.Venta, N.C.Bergenhem, Y.S.Yu, R.E.Tashian.
Ref. Hum Mutat, 1994, 4, 294-296.
PubMed id 7866410
Secondary reference #3
Title Point mutation in the variant of human carbonic anhydrase isozyme i (cai michigan) active site decreases affinity for aromatic sulfonamide inhibitors
Authors F.Briganti, W.R.Chegwidden, A.Scozzafava, C.T.Supuran, R.E.Tashian, K.E.Wiebauer.
Ref. gene fam lsozyme bull, 1998, 31, 43.
Go to PROCHECK summary