Linear free energy relationships implicate three modes of binding for fluoroaromatic inhibitors to a mutant of carbonic anhydrase II

Organic Letters

Volumn 2, Issue 9, 2000, Pages 1189-1192

  Doyon, Jeffrey B ^a   Hansen, Elizabeth A M ^a   Kim, Chu Young ^b   Chang, Jeanne S ^b   Christianson, David W ^b   Madder, Ryan D ^a   Voet, Judith G ^a   Baird Jr , Teaster A ^c   Fierke, Carol A ^c   Jain, Ahamindra ^a  

^a SWARTHMORE COLLEGE   (United States)

^b UNIVERSITY OF PENNSYLVANIA   (United States)

^c UNIVERSITY OF MICHIGAN   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

CARBONATE DEHYDRATASE; CARBONATE DEHYDRATASE INHIBITOR; FLUORINE;

ARTICLE; CHEMICAL STRUCTURE; CHEMISTRY; CRYSTALLOGRAPHY; GENETICS; LINEAR ENERGY TRANSFER; METABOLISM; METHODOLOGY; MUTATION; PROTEIN CONFORMATION;

CARBONIC ANHYDRASE INHIBITORS; CARBONIC ANHYDRASES; CRYSTALLOGRAPHY; FLUORINE; LINEAR ENERGY TRANSFER; MODELS, MOLECULAR; MUTATION; PROTEIN CONFORMATION;

EID: 0034603882     PISSN: 15237060     EISSN: None     Source Type: Journal    
DOI: 10.1021/ol005608r     Document Type: Article

References (17)

1. Jain, A.; Alexander, R. S.; Christianson, D. W.; Whitesides, G. M. J. Med. Chem. 1994, 37, 2100-2105.
2. Doyon, J. B.; Jain, A. Org. Lett. 1999, 1(2), 183-186.
3. DerHovanessian, A.; Doyon, J. B.; Jain, A.; Rablen, P. R.; Sapse, A. M. Org. Lett. 1999, 1(9), 1359-1362.
4. Gao, J.; Qiao, S.; Whitesides, G. M. J. Med. Chem. 1995, 38, 2292-2301.
5. Nair, S. K.; Krebs, J. F.; Christianson, D. W.; Fierke, C. A. Biochemistry 1995, 34, 3981-3989.
6. Krebs, J. F.; Fierke, C. A. J. Biol. Chem. 1993, 268, 948-954.
7. Nair, S. K.; Christianson, D. W. Biochemistry 1993, 32, 4506-4514.
8. 4 (pH 8).
9. Ishihama, Y.; Oda, Y.; Uchikama, K.; Asakawa, N. Anal. Chem. 1995, 67, 1588-1595.
10. 3 (pH 7.0) electrophoresis buffer was analyzed using a Waters Quanta 4000E capillary electrophoresis system. The following parameters were used to determine hydrophobicities: capillary length = 37 cm (30 cm to the detector), 13.5 kV, detection at 214 nm.
11. We noted an interesting trend, however, between the affinities of our library for wt and mutant protein, after normalizing each set of data for the affinity of that protein to the perhydro derivative. Inhibitors having two or fewer fluorines bind more tightly to wt CA, while larger inhibitors prefer the F131V mutant. The only exception to this rule was the 3,4,5-trifluoro derivative, which may project its fluorine substituents out into the larger portion of the conical cleft of CA, avoiding steric clashes with the bulkier active site of the wt protein.
12. The fact that the 2,6-difluorobenzyl-derived CAI binds less tightly than is expected cannot be readily explained by any anomalies in the crystal structure of this inhibitor bound to F131V CA.
13. Hansch, C. W.; McClarin, J.; Klein, T.; Langridge, R. Mol. Pharmacol. 1985, 27, 493-498.
14. The distances between the m-carbon of the of the fluorobenzyl ring and the β-carbon of P202 are 7.15 and 5.80 Å for the wt and mutant, respectively. Similar changes have been observed in crystal structures with five other fluoroaromatic CAIs bound to F131V CA: Kim, C.-Y.; Doyon, J. B.; Baird, T. A.; Fierke, C. A.; Jain, A.; Christianson, D. W., manuscript in preparation.
15. w (ref 14).
16. Dugad, L. B.; Cooley, C. R.; Gerig, J. T. Biochemistry 1989, 28, 3955-3960.
17. These NOE measurements may also rule out the presence of F·H contacts in solution between the inhibitors and backbone amide protons. By examining a crystal structure of the 2,3-derivative bound to wild-type CA, we noted that two N-H groups (residues 131 and 132) could form F·H contacts with bound inhibitor, given a modest conformational change. Such a conformational change in the case of the F131V protein might bring both of these N-H groups within contact distance for fluorines at the ortho and meta positions (a restricted MM2 minimization starting from the geometry found in the crystal structure of the 2,3-derivative bound to wt CA, with F131 replaced by V, in MacroModel 6.0 (Schrodinger, Inc.) allowed amino acids 124-138 to undergo the conformational change required for the F·H contacts).