Guest post by Magnus Palmblad. Tomorrow, May 14, 2022, is the Grand Final of the 66th Eurovision Song Contest, with hundreds of millions of fans across Europe (from Azerbaijan to Australia) spending their Saturday evening watching one of the greatest spectacles on television.

Contaminants, as in the unintended proteinaceous parts of your sample, that, especially in mass spectrometry-based proteomics, are important to think about. This specific writeup is a series of twitter discussions with the real experts as I was analyzing data and led to a quest for contaminant lists, and finding out that these lists are actually being updated!

This is the official start of what could be termed a blog, that sometimes is long.

A deep dive into sources of fasta (for mass spec-based proteomics) and some recommendations