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Synthesis and Bioconjugation of Thiol-Reactive Reagents for the Creation of Site-Selectively Modified Immunoconjugates
Published on: March 6, 2019
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A platform for efficient, thiol-stable conjugation to albumin's native single accessible cysteine
Mark E B Smith1, Mikael B Caspersen, Eifion Robinson
1Department of Chemistry, University College London, London, WC1H 0AJ, UK. j.r.baker@ucl.ac.uk v.chudasama@ucl.ac.uk.
Organic & Biomolecular Chemistry
|June 26, 2015
Summary
Bromomaleimides enable stable albumin conjugate construction via cysteine conjugation and hydrolysis. This method offers improved quantitative hydrolysis and avoids retro-Michael deconjugation, outperforming traditional maleimide approaches.
Area of Science:
- Bioconjugation Chemistry
- Protein Chemistry
Background:
- Classical maleimide chemistry is widely used for protein conjugation.
- However, maleimide conjugates can be unstable due to retro-Michael deconjugation.
Purpose of the Study:
- To introduce bromomaleimides as a novel reagent for creating stable albumin conjugates.
- To compare the stability and hydrolysis characteristics of bromomaleimide conjugates against traditional maleimide conjugates.
Main Methods:
- Conjugation of bromomaleimides to the native cysteine residue of albumin.
- Hydrolysis of the resulting bromomaleimide-albumin adducts.
- Analysis of conjugate stability and hydrolysis efficiency.
Main Results:
- Bromomaleimides successfully formed stable albumin conjugates.
- Quantitative hydrolysis of bromomaleimide conjugates was achieved.
- Undesirable retro-Michael deconjugation was absent in bromomaleimide conjugates.
Conclusions:
- Bromomaleimides provide a superior alternative to maleimides for constructing stable albumin conjugates.
- The method offers enhanced stability and controlled hydrolysis, beneficial for bioconjugation applications.
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