Enzyme I (EI) of the bacterial phosphotransferase system (PTS) utilizes phosphoenolpyruvate (PEP) as a source of energy in order to transport sugars across the cellular membrane. PEP binding to EI initiates a phosphorylation cascade that regulates a variety of essential pathways in the metabolism of bacterial cells. Given its central role in controlling bacterial metabolism, EI has been often suggested as a good target for antimicrobial research. Here, we report the 1HN, 15N, 13C', 1Hmethyl, and 13Cmethyl chemical shifts of the 128 kDa homodimer EI from the thermophile Thermoanaerobacter tengcongensis. In total 79% of the expected backbone amide correlations and 80% of the expected methyl TROSY peaks from U-[2H, 13C, 15N], Ileδ1-[13CH3], Val-Leu-[13CH3/12CD3] labeled EI were assigned. The reported assignments will enable future structural studies aimed at illuminating the fundamental mechanisms governing long-range interdomain communication in EI and at indicating new therapeutic strategies to combat bacterial infections.
Keywords: Backbone resonance assignment; Bacterial phosphotransferase system; Conformational dynamics; Enzyme I; Thermophilic bacteria; Transverse relaxation optimized spectroscopy.