4.A.2.1.28
Nitrogen regulatory phosphoryl transfer chain, E1^Ntr - NPr - IIA^Ntr consisting of three cytolasmic phosphoryl transfer proteins as indicated:  E1^Ntr, PtsP, Enzyme 1-like protein of 759 aas; - NPN in Pseudomonas aeruginosa is phosphorylated by redundant upstream proteins and impacts virulence-related genes (Underhill et al. 2023).  The bacterial nitrogen-related phosphotransfer (PTS^Ntr) system bears homology to PTS systems that facilitate saccharide import and phosphorylation. It influences expression of genes involved in type III secretion, potassium transport, and pyoverdine biosynthesis as well as biofilm formation and virulence (Underhill et al. 2023).  It also regulates the LasI-LasR quorum sensing system (Banerjee et al. 2025).