The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding.
Thiomandelic acid is a simple, broad spectrum, and reasonably potent inhibitor of metallo-beta-lactamases, enzymes that mediate resistance to beta-lactam antibiotics. We report studies by NMR and perturbed angular correlation (PAC) spectroscopy of the mode of binding of the R and S enantiomers of th...
| Автори: | , , , , , , , , |
|---|---|
| Формат: | Journal article |
| Мова: | English |
| Опубліковано: |
2003
|
| _version_ | 1826267147175723008 |
|---|---|
| author | Damblon, C Jensen, M Ababou, A Barsukov, I Papamicael, C Schofield, C Olsen, L Bauer, R Roberts, G |
| author_facet | Damblon, C Jensen, M Ababou, A Barsukov, I Papamicael, C Schofield, C Olsen, L Bauer, R Roberts, G |
| author_sort | Damblon, C |
| collection | OXFORD |
| description | Thiomandelic acid is a simple, broad spectrum, and reasonably potent inhibitor of metallo-beta-lactamases, enzymes that mediate resistance to beta-lactam antibiotics. We report studies by NMR and perturbed angular correlation (PAC) spectroscopy of the mode of binding of the R and S enantiomers of thiomandelic acid, focusing on their interaction with the two metal ions in cadmium-substituted Bacillus cereus metallo-beta-lactamase. The 113Cd resonances are specifically assigned to the metals in the two individual sites on the protein by using 113Cd-edited 1H NMR spectra. Each enantiomer of thiomandelate produces large downfield shifts of both 113Cd resonances and changes in the PAC spectra, which indicate that they bind such that the thiol of the inhibitor bridges between the two metals. For R-thiomandelate, this is unambiguously confirmed by the observation of scalar coupling between Halpha of the inhibitor and both cadmium ions. The NMR and PAC spectra reveal that the two chiral forms of the inhibitor differ in the details of their coordination geometry. The complex with R-thiomandelate, but not that with the S-enantiomer, shows evidence in the PAC spectra of a dynamic process in the nanosecond time regime, the possible nature of which is discussed. The thiomandelate complex of the mononuclear enzyme can be detected only at low metal to enzyme stoichiometry; the relative populations of mononuclear and binuclear enzyme as a function of cadmium concentration provide clear evidence for positive cooperativity in metal ion binding in the presence of the inhibitor, in contrast to the negative cooperativity observed in the free enzyme. |
| first_indexed | 2024-03-06T20:49:45Z |
| format | Journal article |
| id | oxford-uuid:3728ec8b-e2f9-46ce-b31b-ea2892a54b6e |
| institution | University of Oxford |
| language | English |
| last_indexed | 2024-03-06T20:49:45Z |
| publishDate | 2003 |
| record_format | dspace |
| spelling | oxford-uuid:3728ec8b-e2f9-46ce-b31b-ea2892a54b6e2022-03-26T13:42:24ZThe inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding.Journal articlehttp://purl.org/coar/resource_type/c_dcae04bcuuid:3728ec8b-e2f9-46ce-b31b-ea2892a54b6eEnglishSymplectic Elements at Oxford2003Damblon, CJensen, MAbabou, ABarsukov, IPapamicael, CSchofield, COlsen, LBauer, RRoberts, GThiomandelic acid is a simple, broad spectrum, and reasonably potent inhibitor of metallo-beta-lactamases, enzymes that mediate resistance to beta-lactam antibiotics. We report studies by NMR and perturbed angular correlation (PAC) spectroscopy of the mode of binding of the R and S enantiomers of thiomandelic acid, focusing on their interaction with the two metal ions in cadmium-substituted Bacillus cereus metallo-beta-lactamase. The 113Cd resonances are specifically assigned to the metals in the two individual sites on the protein by using 113Cd-edited 1H NMR spectra. Each enantiomer of thiomandelate produces large downfield shifts of both 113Cd resonances and changes in the PAC spectra, which indicate that they bind such that the thiol of the inhibitor bridges between the two metals. For R-thiomandelate, this is unambiguously confirmed by the observation of scalar coupling between Halpha of the inhibitor and both cadmium ions. The NMR and PAC spectra reveal that the two chiral forms of the inhibitor differ in the details of their coordination geometry. The complex with R-thiomandelate, but not that with the S-enantiomer, shows evidence in the PAC spectra of a dynamic process in the nanosecond time regime, the possible nature of which is discussed. The thiomandelate complex of the mononuclear enzyme can be detected only at low metal to enzyme stoichiometry; the relative populations of mononuclear and binuclear enzyme as a function of cadmium concentration provide clear evidence for positive cooperativity in metal ion binding in the presence of the inhibitor, in contrast to the negative cooperativity observed in the free enzyme. |
| spellingShingle | Damblon, C Jensen, M Ababou, A Barsukov, I Papamicael, C Schofield, C Olsen, L Bauer, R Roberts, G The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title | The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title_full | The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title_fullStr | The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title_full_unstemmed | The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title_short | The inhibitor thiomandelic acid binds to both metal ions in metallo-beta-lactamase and induces positive cooperativity in metal binding. |
| title_sort | inhibitor thiomandelic acid binds to both metal ions in metallo beta lactamase and induces positive cooperativity in metal binding |
| work_keys_str_mv | AT damblonc theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT jensenm theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT ababoua theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT barsukovi theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT papamicaelc theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT schofieldc theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT olsenl theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT bauerr theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT robertsg theinhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT damblonc inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT jensenm inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT ababoua inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT barsukovi inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT papamicaelc inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT schofieldc inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT olsenl inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT bauerr inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding AT robertsg inhibitorthiomandelicacidbindstobothmetalionsinmetallobetalactamaseandinducespositivecooperativityinmetalbinding |