Evidence for structural elasticity of class A β-lactamases in the course of catalytic turnover of the novel cephalosporin cefepime

Journal of the American Chemical Society

Volumn 118, Issue 32, 1996, Pages 7441-7448

  Taibi Tronche, Pascale ^a   Massova, Irina ^a   Vakulenko, Sergei B ^b   Lerner, Stephen A ^b   Mobashery, Shahriar ^a  

^a WAYNE STATE UNIVERSITY   (United States)

^b WAYNE STATE UNIVERSITY SCHOOL OF MEDICINE   (United States)

Author keywords

[No Author keywords available]

Indexed keywords

BETA LACTAMASE; CEFEPIME;

AMINO ACID SEQUENCE; ARTICLE; BINDING SITE; CIRCULAR DICHROISM; ENZYME ACTIVITY; ENZYME BINDING; ENZYME STRUCTURE; ESCHERICHIA COLI; HYDROLYSIS; MUTANT;

EID: 0029775843     PISSN: 00027863     EISSN: None     Source Type: Journal    
DOI: 10.1021/ja9529753     Document Type: Article

References (67)

1. Gillum, J. G.; Polk, R. E. Hosp. Formul. 1994, 29, 503. Rybak, M. J.; Palmer, S. M. Am. J. Hosp. Pharm. 1994, 51, 459. Jones, R. N.; Marshall, S. A. Diagn. Microbiol. Infect. Dis. 1994, 19, 33.
2. Gillum, J. G.; Polk, R. E. Hosp. Formul. 1994, 29, 503. Rybak, M. J.; Palmer, S. M. Am. J. Hosp. Pharm. 1994, 51, 459. Jones, R. N.; Marshall, S. A. Diagn. Microbiol. Infect. Dis. 1994, 19, 33.
3. Gillum, J. G.; Polk, R. E. Hosp. Formul. 1994, 29, 503. Rybak, M. J.; Palmer, S. M. Am. J. Hosp. Pharm. 1994, 51, 459. Jones, R. N.; Marshall, S. A. Diagn. Microbiol. Infect. Dis. 1994, 19, 33.
4. Imtiaz, U.; Billings, E.; Knox, J. R.; Manavathu, E. K.; Lerner, S. A.; Mobashery, S. J. Am. Chem. Soc. 1993, 115, 4435-4442. Miyashita, K.; Mobashery, S. Bioorg. Med. Chem. Lett. 1995, 5, 1043.
5. Imtiaz, U.; Billings, E.; Knox, J. R.; Manavathu, E. K.; Lerner, S. A.; Mobashery, S. J. Am. Chem. Soc. 1993, 115, 4435-4442. Miyashita, K.; Mobashery, S. Bioorg. Med. Chem. Lett. 1995, 5, 1043.
6. Imtiaz, U.; Billings, E. M.; Knox, J. R.; Mobashery, S. Biochemistry 1994, 33, 5728.
7. Bulychev, A.; Massova, I.; Lerner, S. A.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 4797.
8. Zafaralla, G.; Mobashery, S. J. Am. Chem. Soc. 1992, 114, 1505.
9. Taibi, P.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 7600.
10. Consensus amino acid numbering system of Ambler et al. for class A β-Iactamases has been used throughout (Ambler, R. P.; Coulson, A. F. W.; Frère, J. M.; Ghuysen, J. M.; Joris, B.; Forsman, M.; Levesque, R. C.; Tiraby, G.; Waley, S. G. Biochem. J. 1991, 276, 269).
11. Vakulenko, S. B.; Toth, M.; Taibi, P.; Mobashery, S.; Lerner, S. A. Antimicrob. Agents Chemother. 1995, 39, 1878.
12. Zafaralla, G.; Manavathu, E. K.; Lerner, S. A.; Mobashery, S. Biochemistry 1992, 31, 3847.
13. Ross G. W. Methods Enzymol. 1975, 43, 678.
14. (a) Strynadka, N. C. J.; Adachi, H.; Jensen, S. E.; Johns, K.; Sielecki, A.; Betzel, C; Sutoh, K.; James, M. N. G. Nature 1992, 359, 700.
15. (b) Jelsch, C.; Mourey, L.; Masson, J. M.; Samama, J. P. Proteins: Struct., Fund., Genet. 1993, 16, 364. Swarén, P.; Maveyraud, L.; Guillet, V.; Masson, J. M.; Mourey, L.; Samama. J. P. Structure 1995, 3, 603.
16. (b) Jelsch, C.; Mourey, L.; Masson, J. M.; Samama, J. P. Proteins: Struct., Fund., Genet. 1993, 16, 364. Swarén, P.; Maveyraud, L.; Guillet, V.; Masson, J. M.; Mourey, L.; Samama. J. P. Structure 1995, 3, 603.
17. Vanish-Perron, C.; Vieira, J.; Messing, J. Gene 1985, 33, 103.
18. Oka, A. H.; Sugisaki, H.; Takanami, M. J. Mol. Biol. 1981, 147, 217.
19. Sutcliffe, J. G. Proc. Natl. Acad. Sci. U.S.A. 1978, 75, 3737.
20. Sowek, J. A.; Singer, S. B.; Ohringer, S.; Malley, M. F.; Dougherty, T. J.; Gougoutas, J. Z.; Bush, K. Biochemistry 1991, 30, 3179.
21. Birnboim, H. C.; Doly, J. Nucleic Acids Res. 1979, 7, 1513.
22. Sanger, F.; Nicklen, S.; Coulson, A. R. Proc. Natl. Acad. Sci. U.S.A. 1977, 74, 5463.
23. Stewart, J. J. P. QCPE program 455.
24. Weiner, S. J.; Kollman P. A.; Case, D. A.; Singh, U. C.; Ohio, C.; Alagona, G.; Profeta, S.; Weiner, P. J. Am. Chem. Soc. 1984, 106, 765.
25. Sybyl, version 6.22. Tripos, Inc, 1699 South Hanley Road, St. Louis, MO 63144-2913.
26. Kuzin, A. P.; Liu, H.; Kelly, J. A.; Knox, J. R. Biochemistry 1995, 34, 9532.
27. Kelly, J. A.; Dideberg, O.; Charlier, P.; Wery, J. P.; Libert, M.; Moews, P. C.; Knox, J. R.; Duez, C.; Fraipont, C.; Joris, B.; Dusart, J.; Frère, J. M.; Ghuysen, J. M. Science 1986, 231, 1429.
28. Bulychev, A.; O'Brien, M. E.; Massova, I.; Teng, M.; Gibson, T. A.; Miller, M. J.; Mobashery, S. J. Am. Cham. Soc. 1995, 117, 5938.
29. Grabowski, E. J. J.; Douglas, A. W.; Smith, G. B. J. Am. Chem. Soc. 1985, 107, 267. Page, M. I. Acc. Chem. Res. 1984, 17, 144. Page, M. I.; Procter, P. J. Am. Chem. Soc. 1984, 106, 3829. Faraci, W. S.; Pratt, R. F. J. Am. Chem. Soc. 1984, 106, 1489.
30. Grabowski, E. J. J.; Douglas, A. W.; Smith, G. B. J. Am. Chem. Soc. 1985, 107, 267. Page, M. I. Acc. Chem. Res. 1984, 17, 144. Page, M. I.; Procter, P. J. Am. Chem. Soc. 1984, 106, 3829. Faraci, W. S.; Pratt, R. F. J. Am. Chem. Soc. 1984, 106, 1489.
31. Grabowski, E. J. J.; Douglas, A. W.; Smith, G. B. J. Am. Chem. Soc. 1985, 107, 267. Page, M. I. Acc. Chem. Res. 1984, 17, 144. Page, M. I.; Procter, P. J. Am. Chem. Soc. 1984, 106, 3829. Faraci, W. S.; Pratt, R. F. J. Am. Chem. Soc. 1984, 106, 1489.
32. Grabowski, E. J. J.; Douglas, A. W.; Smith, G. B. J. Am. Chem. Soc. 1985, 107, 267. Page, M. I. Acc. Chem. Res. 1984, 17, 144. Page, M. I.; Procter, P. J. Am. Chem. Soc. 1984, 106, 3829. Faraci, W. S.; Pratt, R. F. J. Am. Chem. Soc. 1984, 106, 1489.
33. The water molecules in the crystal coordinates for the TEM-1 β-lactamase which were made available to us were not numbered. Hence, the numbering system for the water molecules is that of the related Bacillus lichenifomis enzyme, as proposed by Knox and Moews (Knox, J. R.; Moews, P. C. J. Mol. Biol. 1991, 220, 435).
34. Matagne, A.; Lamotte-Brasseur, J; Frère, J. M. Eur. J. Biochem. 1993, 217, 61. Monk, J.; Waley, S. G. Biochem. J. 1988, 253, 323.
35. Matagne, A.; Lamotte-Brasseur, J; Frère, J. M. Eur. J. Biochem. 1993, 217, 61. Monk, J.; Waley, S. G. Biochem. J. 1988, 253, 323.
36. Brooks, C. L.; Karplus, M.; Pettitt, B. M. In Proteins: A Theoretical Perspective of Dynamics, Structure, and Thermodynamics; Advances in Chemical Physics, Volume LXXI; John Wiley & Sons: New York, 1988.
37. We suspect that the Tripos force-field parameters may underestimate some interactions (e.g., hydrogen bonding) and overestimate others, with the effects becoming more pronounced with elevated temperature. However, these opposing effects have a tendency to even each other out. Although we are aware of this caveat, the results of the simulations are generally reliable, and in this case, they are supported by experimental observations.
38. Collatz, E.; Tran Van Nhieu, G.; Billot-Klein, D.; Willianson, R.; Gutmann, L. Gene 1989, 78, 349.
39. Palzkill, T.; Le, Q. Q.; Venkatachalam, K. V.; LaRocco, M.; Ocera, H. Mol. Microbiol. 1994, 12, 217.
40. Raquet, X.; Lamotte-Brasseur, J.; Fonzé, E.; Goussard, S.; Courvalin, P.; Frère, J. M. J. Mol. Biol. 1994, 244, 625.
41. pUC19 β-lactamase is in general even more active than the Ser-164 enzyme (unpublished results). However, Asn-164 has not yet been observed clinically.
42. Adachi, H.; Ohta, T.; Matsuzawa, H. J. Biol. Chem. 1991, 260, 3186. Escobar, W. A.; Tan, A. K.; Fink, A. L. Biochemistry 1991, 30, 10783. Miyashita, K.; Massova, I.; Taibi, P.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 11055. Maveyraud, L.; Massova, I.; Birck, C.; Miyashita, K.; Samama, J.-P.; Mobashery, S. J. Am. Chem. Soc. 1996, 118, 7435.
43. Adachi, H.; Ohta, T.; Matsuzawa, H. J. Biol. Chem. 1991, 260, 3186. Escobar, W. A.; Tan, A. K.; Fink, A. L. Biochemistry 1991, 30, 10783. Miyashita, K.; Massova, I.; Taibi, P.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 11055. Maveyraud, L.; Massova, I.; Birck, C.; Miyashita, K.; Samama, J.-P.; Mobashery, S. J. Am. Chem. Soc. 1996, 118, 7435.
44. Adachi, H.; Ohta, T.; Matsuzawa, H. J. Biol. Chem. 1991, 260, 3186. Escobar, W. A.; Tan, A. K.; Fink, A. L. Biochemistry 1991, 30, 10783. Miyashita, K.; Massova, I.; Taibi, P.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 11055. Maveyraud, L.; Massova, I.; Birck, C.; Miyashita, K.; Samama, J.-P.; Mobashery, S. J. Am. Chem. Soc. 1996, 118, 7435.
45. Adachi, H.; Ohta, T.; Matsuzawa, H. J. Biol. Chem. 1991, 260, 3186. Escobar, W. A.; Tan, A. K.; Fink, A. L. Biochemistry 1991, 30, 10783. Miyashita, K.; Massova, I.; Taibi, P.; Mobashery, S. J. Am. Chem. Soc. 1995, 117, 11055. Maveyraud, L.; Massova, I.; Birck, C.; Miyashita, K.; Samama, J.-P.; Mobashery, S. J. Am. Chem. Soc. 1996, 118, 7435.
46. Waley, S. G. In The Chemistry of β-Lactams; Page, M. I., Ed.; Blackie Academic: London, 1992; pp 223-224.
47. Christensen, H.; Martin, M. T.; Waley, S. G. Biochem. J. 1990, 266, 853.
48. For an analysis of CD spectra of proteins, consult: Jirgenson, B. In Optical Activity of Proteins and Other Macromolecules; Springer Verlag: New York, NY, 1973; pp 66-74.
49. For reasons not readily obvious to us, we have not been able to purify the Asp-179-Gly mutant β-lactamase to homogeneity in the large quantities needed for the CD measurements.
50. Herzberg, O.; Kapadia, G.; Blanco, B.; Smith, T. S.; Coulson, A. Biochemisty 1991, 30, 9503.
51. Martin, M. T.; Waley, S. G. Biochem. J. 1988, 254, 923.
52. Bicknell, R.; Waley, S. G. Biochem. J. 1985, 231, 83.
53. Anderson, E. G.; Pratt, R. F. J. Biol. Chem. 1981, 256, 11401.
54. Anderson, E. G.; Pratt, R. F. J. Biol. Chem. 1983, 258, 13120.
55. Fraci, W. S.; Pratt, R. F. Biochemistry 1985, 24, 903.
56. In derivations of the integrated forms for the equations that describe the pre-steady-state treatment of enzyme kinetics, some assumptions are made which may not be valid at all times. These assumptions would introduce errors in the measured values for microscopic constants from stopped-flow experiments which are often not appreciated.
57. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
58. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
59. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
60. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
61. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
62. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
63. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
64. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
65. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
66. Samuni, A.; Citri, N. Biochem. Biophvs. Res. Commun. 1975, 62, 7. Citri, N.; Samuni, A.; Zyk, N. Proc. Natl. Acad. Sci. U.S.A. 1976, 73, 1048. Virden, R.; Bristow, A. F.; Pain, R. H. Biochem. Biophys. Res. Commun. 1978, 82, 951. Klemes, Y.; Citri, N. Biochem. J. 1980, 187, 529. Citri, N.; Kalkstein, A.; Samuni, A.; Zyk, N. Eur. J. Biochem. 1984, 144, 333. Persaud, K. C.; Pain, R. H.; Virden, R. Biochem. J. 1986, 237, 723. Page, M. G. P. Biochem. J. 1993, 295, 295. Dubus, A.; Normark, S.: Kanai, M.; Page, M. G. P. Biochemistry 1995, 34, 7757. The above references correlate the observation of a decrease in the activity of β-lactamases in the course of turnover of certain substrates as evidence for conformational changes for the enzyme during catalysis, but no direct evidence besides the attenuation of activity is presented in these reports. We wish to point out that Charnas and Knowles (Biochemistry 1981, 20, 2732) also noted such attenuation in the rate of turnover of an olivanic acid substrate by the TEM β-lactamase, but they dismissed the argument for a conformational change on kinetic grounds in that case. However, it may be likely that in some cases discussed in the above references conformational changes may be playing a role in catalysis. More recently Jamin et al. have observed changes in the NMR spectrum of the B. licheniformis β-lactamase, which they attribute to conformational changes in the course of catalysis (Jamin, M.; Damblon, C.; Bauduin-Misselyn, A. M.; Durant, F.; Roberts, G. C. K.; Charlier, P.; Llabres, G.; Frère, J. M. Biochem. J. 1994. 301, 199).
67. Vijayakumar, S.; Ravishanker, G.; Pratt, R. F.; Beveridge, D. L. J. Am. Chem. Soc. 1995, 117, 1722.