Calibration of mass spectrometric peptide mass fingerprint data without specific external or internal calibrants

Background: Peptide Mass Fingerprinting (PMF) is a widely used mass spectrometry (MS) method of analysis of proteins and peptides. It relies on the comparison between experimentally determined and theoretical mass spectra. The PMF process requires calibration, usually performed with external or internal calibrants of known molecular masses. Results: We have introduced two novel MS calibration methods. The first method utilises the local similarity of peptide maps generated after separation of complex protein samples by twodimensional gel electrophoresis. It computes a multiple peak-list alignment of the data set using a modified Minimum Spanning Tree (MST) algorithm. The second method exploits the idea that hundreds of MS samples are measured in parallel on one sample support. It improves the calibration coefficients by applying a two-dimensional Thin Plate Splines (TPS) smoothing algorithm. We studied the novel calibration methods utilising data generated by three different MALDI-TOF...

• Type: Journal
• Year: 2005
• Where: BMCBI
• Authors: Witold E. Wolski, Maciej Lalowski, Peter Jungblut, Knut Reinert
• Keywords: BMCBI 2005, Calibration, Calibration Algorithm, Internal Calibrants