An Optimised Di-Boronate-ChemMatrix Affinity Chromatography to Trap Deoxyfructosylated Peptides as Biomarkers of Glycation

Abstract

We report herein a novel ChemMatrix® Rink resin functionalised with two phenylboronate (PhB) moieties linked on the N-α and N-ε amino functions of a lysine residue to specifically capture deoxyfructosylated peptides, compared to differently glycosylated peptides in complex mixtures. The new PhB-Lys(PhB)-ChemMatrix® Rink resin allows for exploitation of the previously demonstrated ability of cis diols to form phenylboronic esters. The optimised capturing and cleavage procedure from the novel functionalised resin showed that only the peptides containing deoxyfructosyl-lysine moieties can be efficiently and specifically detected by HR-MS and MS/MS experiments. We also investigated the high-selective affinity to deoxyfructosylated peptides in an ad hoc mixture containing unique synthetic non-modified peptides and in the hydrolysates of human and bovine serum albumin as complex peptide mixtures. We demonstrated that the deoxyfructopyranosyl moiety on lysine residues is crucial in the capturing reaction. Therefore, the novel specifically-designed PhB-Lys(PhB)-ChemMatrix® Rink resin, which has the highest affinity to deoxyfructosylated peptides, is a candidate to quantitatively separate early glycation peptides from complex mixtures to investigate their role in diabetes complications in the clinics.

Veni, Vidi, Vici: Immobilized Peptide-Based Conjugates as Tools for Capture, Analysis, and Transformation

“…In this review, we concentrated on our recent research to develop materials functionalized with different functional groups, in order to effectively enrich the sample into the selected analytes [7,8,19,29,80]. Despite the significant development of mass spectrometry coupled with liquid chromatography (LC-MS) and bioinformatics methods, the analysis of biological samples, in particular, the search and identification of new biomarkers present in trace amounts, is still a challenge [11,28,42,43].…”

“…We focused on the selective enrichment and detection of biologically significant compounds that could be used as the markers of diseases, such as diabetes [7,43] or preeclampsia [19]. We applied commercially available solid supports (TentaGel R RAM, ChemMatrix Rink) as the starting materials, which were further functionalized with appropriate functional groups and linkers.…”

“…The qualitative and quantitative analysis of glycated peptides in plasma samples was employed in the search for biomarkers that may allow for the early diagnosis of type 2 diabetes mellitus [45]. In our recent paper, we reported the affinity and selective binding of glycated peptides in complex peptide mixtures, obtained from hydrolysis of human and bovine serum albumin by a novel ChemMatrix ® Rink resin functionalized with two phenylboronate (PhB) moieties attached to the N-α and N-ε amino groups of a lysine residue (Figure 5) [7]. The innovative approach was based on one solid support to both synthesize a linker containing phenylboronic acid derivatives and carry out an efficient procedure for the enrichment of a biological sample.…”

“…Currently, the methods of enriching the sample in specific peptides by immobilizing them are intensively investigated. Examples include various ways of capturing cysteinecontaining peptides [4], but can be also tailored for enriching samples in post-translationally modified peptides, such as phosphorylated [5], citrullinated [6] or glycated [7] species. In some cases, a simple enrichment is not enough, as the analyzed biomarker is poorly ionizable in mass spectrometry-examples include steroids, such as cholesterol.…”

Proposal of the Annotation of Phosphorylated Amino Acids and Peptides Using Biological and Chemical Codes

“…There is no unique system for annotating modifications of amino acid residues in sequences. Parentheses “( )“ are used to indicate modifications [ 50 , 59 ]. We propose writing symbols of modifications in the following brackets “[…]”.…”