The Wittig bioconjugation of maleimide derived, water soluble phosphonium ylides to aldehyde-tagged proteins

Abstract

The novel bioconjugation method makes use of maleimides and tris(2-carboxyethyl)phosphine (TCEP) to conjugate small molecules to proteins via alkenes.

More than just Alkene Construction – Re‐Using Wittig Reactions/Reagents in Biomacromolecular Labeling, Imaging, Sequencing and Modification

“…[8] However, given that the aldehyde group is a relatively reactive towards the cross-coupling reactions with various nucleophilic reagents in the cell, including amino, tyrosine, tryptophan, and others, a crucial focus for future endeavors should be on preventing interference from these side reactions. [9] In addition to traditional C=C formation reactions, Wittig reagents can also be utilized in the formation of CÀ S bonds. Sulfenic acid is a significant post-translational modification found on cysteine residues.…”

“…The cells exhibited a significant rise in fluorescence intensity, however cells treated with 17 alone displayed weak fluorescence (Scheme 2d) [8] . However, given that the aldehyde group is a relatively reactive towards the cross‐coupling reactions with various nucleophilic reagents in the cell, including amino, tyrosine, tryptophan, and others, a crucial focus for future endeavors should be on preventing interference from these side reactions [9] …”

Cross aldol OPAL bioconjugation outcompetes intramolecular hemiaminal cyclisation of proline adjacent N-terminal α-oxo aldehydes at acidic pH

“…Although highly effective, the modication of N-terminal a-oxo aldehydes has predominantly relied on aldehyde-heteroatom coupling chemistry 15 which affords linkages that have proved to be unstable in vivo, with damaging consequences. 16 This has motivated researchers to explore new approaches for the synthesis of more stable bioconjugates, recently leading to the development of methods for the construction of stable C-C bonds [17][18][19][20][21][22][23] using protein aldehydes as reaction partners. 24,25 Our own work in this eld has included the development of an organocatalystmediated protein aldol ligation (OPAL) 26 that efficiently affords a C-C linkage at neutral pH through cross aldol coupling of small molecule aldehyde donors and proteins bearing a-oxo aldehyde acceptors.…”

Ordered Porous Layer Interferometry for Dynamic Observation of Non-Specific Adsorption Induced by 1-Ethyl-3-(3-(dimethylamino)propyl) Carbodiimide

“…Bioconjugation is an essential step in extensive biochemical schemes because it provides possibilities to design and discover new biomolecules or biomaterials, which is key in the biomedical, diagnostic, microelectronic, and material fields. In the past, many efforts toward bioconjugation techniques have focused on coupling efficiency, product stability, and toxicity. − However, little attention has been paid to nonspecific adsorption (NSA) induced by bioconjugation processes by the lack of relevant in vitro models and problems in assessing the rapid and dynamic interactions between bioconjugates and biofluids.…”