Dual-Metal Centered Zirconium–Organic Framework: A Metal-Affinity Probe for Highly Specific Interaction with Phosphopeptides

Abstract

The highly specific affinity between probes and phosphopeptides is the fundamental interaction for selective identification of phosphoproteomes that uncover the mechanisms of signal transduction, cell cycle, enzymatic regulation, and gene expression in biological systems. In this study, a metal-affinity probe possessing both interactions of metal oxide affinity chromatography (MOAC) and immobilized metal ion affinity chromatography (IMAC) was facilely prepared by immobilizing zirconium(IV) on a zirconium-organic framework of UiO-66-NH, which holds dual-metal centers of not only the inherent Zr-O cluster but also the immobilized Zr(IV) center. This dual-metal centered zirconium-organic framework (DZMOF) demonstrates as a highly specific metal-affinity probe toward the extraction of phosphopeptides due to the metal-affinity interactions of MOAC and IMAC toward either mono-phosphorylated or multi-phosphorylated peptides. The binding energies of zirconium 3d and 3d in this DZMOF are 183.07 and 185.47 eV, respectively, which are higher than those of the intact UiO-66-NH (182.84 and 185.17 eV, respectively), confirming the higher metal-affinity interaction between the DZMOF and phosphopeptides. This high metal-affinity probe presents an unprecedented strong performance in anti-nonspecific interference during the capturing of phosphopeptides of β-casein with the molar ratio of β-casein vs bovine serum albumin up to ca. 1:5000. The enrichment of phosphopeptides from a human saliva sample by DZMOF further confirms the great potential of DZMOF in the extraction of low-abundance phosphopeptides for real complex biological samples.

Recent trends in sorbents for bioaffinity chromatography

“…Oxide form of the ion is more stable than the metal ion form [18] Better tolerance to salts, detergents and solvents, Good sensitivity and selectivity [18] High specificity Particular affinity of metal oxides to phosphate groups [19] MOAC materials are preferred for a extraction of monophosphorylated peptides [20] Combined with IMAC, mono-and multiple-phosphopeptides can be captured simultaneously [20][21][22] Glycopeptides and phosphopeptides can be captured simultaneously, by combining with other mechanisms such as HILIC, IMAC [23] Non-specific binding [24] Poor selectivity [25] Low adsorption efficiency [25] Significant loss of phosphorylated proteins during the wash steps [25] A decrease in enrichment yield due to time-consuming separation procedure with traditional MOAC materials [21] Boronate affinity chromatography (BAC)…”

“…Therefore, the combined use of IMAC or MOAC for phosphoproteome analysis should provide an advantage during the enrichment, by increasing the isolation efficiency. Metal-organic framework (MOF)-based materials used for IMAC and MOAC have attracted increasing research interest, and the publications on design and synthesis of these materials have seriously increased in recent years [20][21][22]56]. Peng et al used dual-metal centered zirconium−organic framework to investigate the performance of these sorbents in the enrichment of phosphopeptides from a human saliva sample [20].…”

Nanomaterials in Proteomics

“…Zhou et al immobilized Ti(IV) ions onto UiO‐66–NH 2 by using ATP as linker (Figure C), which exhibited 100 mg g −1 of binding capacity and 84.8% of enrichment recovery . Peng et al immobilized Zr(IV) ions onto UiO‐66–NH 2 by using POCl 3 as linker (dubbed DZMOF, Figure D), and identified 17 phosphopeptides (5 mono‐ and 12 multiphosphopeptides) from 5 µL human saliva . They furtherly modified diphosphorylated fructose on the DZMOF, which was endowed with the ability to deny the binding of monophosphopeptids .…”

In situ synthesis of a novel metal oxide affinity chromatography affinity probe for the selective enrichment of low‐abundance phosphopeptides

“…11 Thus, it is important to adopt effective enrichment methods to specifically select phosphopeptides from complex biological samples. 12 Among the enrichment strategies that have been developed so far, 13,14 metal oxide affinity chromatography (MOAC), 15,16 which is based on reversible Lewis acid-base interactions between the metal oxides and the negatively charged phosphate groups to achieve the specific selection of phosphopeptides, is one of the most widely used and the one with the most potential. 17,18 Various metal oxides, such as lanthanum oxide, 19 zirconium oxide, 20 and titania, 21 have been developed and widely used for the effective enrichment of phosphopeptides.…”