Mass Spectrometry-Based Metabolic Fingerprinting Contributes to Unveil the Role of RSUME in Renal Cell Carcinoma Cell Metabolism.

Clear cell renal cell carcinoma (ccRCC) is a heterogeneous disease with 50-80% patients exhibiting mutations in the von Hippel-Lindau (VHL) gene. RSUME (RWD domain (termed after three major RWD-containing proteins: RING finger-containing proteins, WD-repeat-containing proteins, and yeast DEAD (DEXD)-like helicases)-containing protein small ubiquitin-related modifier (SUMO) enhancer) acts as a negative regulator of VHL function in normoxia. A discovery-based metabolomics approach was developed by means of ultraperformance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (MS) for fingerprinting the endometabolome of a human ccRCC cell line 786-O and three other transformed cell systems ( = 102) with different expressions of RSUME and VHL.

Recombinant human follicle stimulating hormone purification by a short peptide affinity chromatography.

Peptide KVPLITVSKAK was selected to design a synthetic ligand for affinity chromatography purification of recombinant human follicle stimulating hormone (rhFSH), based on the interaction of the hormone with the exoloop 3 of its receptor. The peptide was acetylated to improve its stability to degradation by exopeptidases. A cysteine was incorporated at the C-termini to facilitate its immobilization to the chromatographic activated SulfoLink agarose resin.

Combinatorial Library Screening Coupled to Mass Spectrometry to Identify Valuable Cyclic Peptides.

Combinatorial library screening coupled to mass spectrometry (MS) analysis is a practical approach to identify useful peptides. Cyclic peptides can have high biological activity, selectivity, and affinity for target proteins, and high stability against proteolytic degradation. Here we describe two strategies to prepare combinatorial libraries suitable for MS analysis to accelerate the discovery of cyclic peptide structures.

Latest Advances in OBOC Peptide Libraries. Improvements in Screening Strategies and Enlarging the Family From Linear to Cyclic Libraries.

Solid phase screenings of one bead one compound (OBOC) libraries have been widely used to find ligands with pharmacological and analytical uses, and to purify or detect proteins in complex mixtures. To improve library screening, in the last years various strategies have been developed to avoid the selection of false positive beads and to obtain selective ligands. Currently, there is great interest in cyclic peptides because of their resistance to enzymatic degradation and higher selectivity compared to their linear counterparts.

A simple protocol for combinatorial cyclic depsipeptide libraries sequencing by matrix-assisted laser desorption/ionisation mass spectrometry.

Short cyclic peptides have a great interest in therapeutic, diagnostic and affinity chromatography applications. The screening of 'one-bead-one-peptide' combinatorial libraries combined with mass spectrometry (MS) is an excellent tool to find peptides with affinity for any target protein. The fragmentation patterns of cyclic peptides are quite more complex than those of their linear counterparts, and the elucidation of the resulting tandem mass spectra is rather more difficult.

Friendly strategy to prepare encoded one bead-one compound cyclic peptide library.

One bead-one peptide libraries allow the screening of suitable ligands for any target protein. Short cyclic peptides are ideal ligands for affinity chromatography because of their high affinity and selectivity for the target protein and stability against proteases. We designed a library synthesis strategy to facilitate the identification of cyclic peptides by MS consisting of (a) sequential incorporation of a mixture of Fmoc-Ala-OH and Fmoc-Asp[2-phenylisopropyl (OPp)]-OH (15:85) to Gly-oxymethylbenzamide-ChemMatrix (Gly-HMBA-CM) resin, (b) synthesis of the combinatorial library on the resin by the divide-couple-recombine method, (c) removal of OPp with 4% TFA, (d) peptide cyclization on solid phase through side-chain Asp and amino terminus, and (e) removal of side chain protecting groups with a 95% TFA cocktail.