4 research outputs found
Single-Step Enrichment of <i>N</i>‑Glycopeptides and Phosphopeptides with Novel Multifunctional Ti<sup>4+</sup>-Immobilized Dendritic Polyglycerol Coated Chitosan Nanomaterials
Protein
glycosylation and phosphorylation, two of the most important
post-translational modifications (PTMs) in the proteome, play a vital
role in regulating a number of complex biological processes and involvement
in a variety of diseases. Comprehensive characterization of the phosphoproteome
and glycoproteome requires highly specific and sensitive enrichment
methods of purification of phosphopeptides and glycopeptides because
many glycoproteins and phosphoproteins naturally occur at low abundances
and substoichiometry. Here, we reported a facile route to fabricate
a novel multifunctional Ti<sup>4+</sup>-mmobilized dentritic polyglycerol
CS@PGMA@IDA (CS, chitosan; PGMA, polyÂ(glycidyl methacrylate); IDA,
iminodiacetic acid) nanomaterials. The polymer surface endows the
nanomaterials with biocompatibility, excellent hydrophilic property,
and a large amount of Ti <sup>4+</sup> which have the property of
immobilized metal ion affinity chromatography (IMAC)- and hydrophilic
interaction liquid chromatography (HILIC)-based functional materials.
The CS@PGMA@IDA-Ti<sup>4+</sup> nanomaterials demonstrate an outstanding
ability for <i>N</i>-glycopeptides and phosphopeptides enrichment
simultaneously, evaluated by the extremely high binding capacity (150
mg g<sup>–1</sup>), sensitivity (above 0.1 fmol), and high
enrichment recovery (above 75.4%). Its outstanding specificity and
efficiency for purification of phosphopeptides is reflected in quantities
as low as 1:5000 molar ratios of phosphopeptides which can be detected.
Furthermore, we used CS@PGMA@IDA-Ti<sup>4+</sup> to enrich for <i>N</i>-glycopeptides and phosphopeptides followed by PNGase F
treatment, fractionated and separated <i>N</i>-glycopeptides
and phosphopeptides with different eluents, and then analyzed by MS,
a total of 423 (84.4 ID/μg, 3.525 ID/min) <i>N</i>-glycopeptides in 235 different glycoproteins and 422 (84.4 ID/μg,
3.517 ID/min) phosphopeptides in 256 different phosphoproteins which
were finally identified in two independent LC–MS/MS runs (with
a total time of 120 min) from 50 μg of mouse liver. The results
demonstrated that the method based on CS@PGMA@IDA-Ti<sup>4+</sup> to
single-step enrichment of <i>N</i>-glycopeptides and phosphopeptides
is simple, efficient, specific, and compatible to MS. It can be expected
that CS@PGMA@IDA-Ti<sup>4+</sup> would hold great applicability of
modification-based proteomics to the precious and low amounts of clinical
samples
Efficient Electrochemical Synthesis, Antimicrobial and Antiinflammatory Activity of 2–amino-5-substituted- 1,3,4-oxadiazole Derivatives
An efficient electrochemical method for the preparation of 2-amino-5-substituted-1,3,4-oxadiazoles (4a-k) at platinum anode through the electrooxidation of semicarbazone (3a-k) at controlled potential electrolysis has been reported in the present study. The electrolysis was carried out in the acetic acid solvent and lithium perchlorate was used as supporting electrolyte. The products were characterized by IR,1H-NMR,13C-NMR, mass spectra and elemental analysis. The synthesized compounds were screened for their in vitro growth inhibiting activity against different strains of bacteria viz., Klebsilla penumoniae, Escherichia coli, Bassilus subtilis and Streptococcus aureus and antifungal activity against Aspergillus niger and Crysosporium pannical and results have been compared with the standard antibacterial streptomycin and antifungal griseofulvin. Compounds exhibits significant antibacterial activity and antifungal activity. Compounds 4a and g exhibited equal while 4c, d, i and j slightly less antibacterial activity than standard streptomycin. Compounds 4a and g exhibited equal while 4b, c, d, f and i displayed slightly less antifungal activity than standard griseofulvins