Interactions of Ser22 and 23 with cTnC Lys39 are formed upon phosphorylation. In the unphosphorylated state there is no ionic interaction of the Ser22 and 23 with cTnC Lys39, upon phosphorylation the ionic interactions with Ser22 and 23 exist for ~80% of the simulations (green circle). The resulting shift of NcTnI-NcTnC interactions changes the location of NcTnI on NcTnC and results in Lys39 in the B helix being pulled towards the phosphorylated serines of NcTnI, confirmed by the formation of a hydrogen bond interaction between cTnC Thr38 and cTnI. As a consequence, there is also a very noticeable change in the orientation of the end of the B helix relative to the A helix. There is a loss of interaction of NcTnC Glu40 with NcTnI Arg20/21. Uniquely, there is a strong phosphorylation effect on the aromatic interaction of the Phenylalanine residues in the A and D helices. Whilst the interaction between the end of the A helix Phe24 with the start of the D helix Phe74 and 77 is relatively constant, the very end of the A helix Phe27 increases its interaction upon phosphorylation with the D helix Phe77.