Figure 7.

Mass spectrometry peptide analysis of a cross-linked (CL) azido-biotinylated-cGMP (Azido-BIO-cGMP) sample. The sample was separated in a 10% Tris-HCL gel, stained with Coomassie SimplyBlue SafeStain, and a gel slice corresponding to molecular size of NKA (approx. 110 kDa) was excised and processed for mass spectrometry. The underlined red bold sequences indicate tryptic peptides identified by mass spectrometry when searched against the NCBI Rattus Norvegicus reference sequence using Byonic by Protein Metrics. Peptides were accepted with a false discovery rate of 1%. We identified 47 unique peptides covering 46.1% of the NKA amino acid sequence (472/1023 residues).