Sequencing package.

Peptide Composer is a composition based sequencing (CBS) software package available to all FT-ICR mass spectrometer users. Composition based sequencing is a method for the mass spectrometrical determination of the amino acid sequence of unknown peptides, which are not necessarily listed in protein or other databases. Different from the de novo sequencing approach, CBS is based on a two-step process. In the first step, the amino acid composition of an unknown peptide is determined on the basis of accurate mass values of the peptide precursor ion and of a small number of accurate fragment ion mass values. This is possible using FT-ICR mass spectrometrical data, using the software package Peptide Composer and without employing protein database information or other pre-information. In the second step, the sequence of the found amino acids of the peptide is determined by the program by scoring the agreement between expected and observed fragment ion signals of the permuted sequences. The CBS approach is said to be highly efficient and fast.

GSG Mess- und Analysengerate

Circle 87 on card