Spectral quality overrides software score-A brief tutorial on the analysis of peptide fragmentation data for mass spectrometry laymen.

The use of mass spectrometry has dramatically increased the research pace in the life sciences. The influence of the technique is enormous and its results can have far-reaching consequences such as jail time when applied in forensics. Therefore, analytical chemists trained in proper procedure know that they must validate their experiments. However, those quality measures have not been adopted in a similar manner in the omics technologies even though the stakes are equally high. Reasons are, among others, the segregation of the data generation and data mining functions and an undue belief in software capabilities. In this article, problematic issues such as false or overinterpretation of data are discussed, and assistance is provided for mass spectrometry laymen to evaluate the quality of their results; a quick guide to mass spectral data interpretation of peptide fragmentation experiments, the basis of bottom-up proteomics, is offered. Good science can only be generated in tight collaboration of principal investigator, analytical chemist, and bioinformatician so that the limits and the potential of each method and approach can be responsibly communicated.