Annals of clinical and laboratory science

Screening High Abundance of Peptide for Making Examination Possible in Human Urine.

PMID 26116589


We aim to explore and identify the high abundance of peptides in urine. Random urine samples from 30 healthy individuals were purified by weak cationic-exchange magnetic beads (MB-WCX) and then analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Then the generated mass spectra of peptides were handled by ClinPro-Tools2.1 bioinformatics software and the high abundance of urinary peptide was filtered. Subsequently, the amino acid sequences of highly expressed peptides were identified by a nano-liquid chromatography-tandem mass spectrometry and the corresponding protein names were found by Sequest search. There were 159 urinary peptides of which mass to charge ratios (m/z) varied between 1,000 and 10,000 in the 30 healthy samples. Only peaks with average intensity >600 and the frequency >50% in the whole group were filtered. There were 15 peptides passed though the threshold and they were identified as fragments of fibrinogen alpha chain precursor, vitronectin precursor, inter-alpha-trypsin inhibitor heavy chain H4, complement component 3, prothrombin, apolipoprotein C-II, and alpha-fetoprotein. These urinary peptides could be used for further research on urine.