Determination of Binding Constants of Polyethylene Glycol Vancomycin Derivatives to Peptide Ligands Using Affinity Capillary Electrophoresis
Abstract
Vancomycin (Van) from Streptomyces orientalis has been derivatized with polyethylene glycol [PEG; PEG-550 (1), 750 (2), 1,100 (3), 2,000 (4), 5,000 (5), and 8,000 (6) g mol−1] at the N-terminus of the glycopeptide backbone and their binding to d-Ala-d-Ala terminus peptides assessed using affinity capillary electrophoresis (ACE). Utilizing ACE, a plug of Van-PEG and non-interacting standards are injected and electrophoresed. Analysis of the change in the relative migration time ratio of the Van-PEG species, relative to the non-interacting standards, as a function of the concentration of peptide, yields a value for the binding constant (K_b). Values of K_b for N-acetyl-d-Ala-d-Ala, 7 to the Van-PEG derivatives are weaker than those for N_α,N_ε-diacetyl-Lys-d-Ala-d-Ala, 8 (for example, values of K_b for 7-1 and 8-1 are 1.8 and 47.7 × 10^3 M^(−1), respectively). These results demonstrate that derivatization of Van with PEG has little effect on the affinity of d-Ala-d-Ala peptide ligands to it. The findings further prove the versatility of ACE and its ability to estimate binding parameters of ligands to antibiotics.
Additional Information
© Friedr. Vieweg & Sohn Verlag/GWV Fachverlage GmbH 2006. Received: 2 August 2006 / Revised: 7 November 2006 / Accepted: 21 November 2006 / Online publication: 21 December 2006 The authors gratefully acknowledge financial support for this research by grants from the National Science Foundation (CHE-0515363, DMR-0351848, DMR-0080065, DMR-0520565), and the National Institutes of Health (1R15 AI055515-01, 1R15AI65468-01, and GM54939).Additional details
- Eprint ID
- 76264
- Resolver ID
- CaltechAUTHORS:20170408-165046683
- NSF
- CHE-0515363
- NSF
- DMR-0351848
- NSF
- DMR-0080065
- NSF
- DMR-0520565
- NIH
- 1R15 AI055515-01
- NIH
- 1R15AI65468-01
- NIH
- GM54939
- Created
-
2018-03-09Created from EPrint's datestamp field
- Updated
-
2021-11-15Created from EPrint's last_modified field