Structure and conformational stability of the enzyme I of Streptomyces coelicolor explored by FTIR and circular dichroism.
The bacterial phosphoenolpyruvate (PEP): sugar phosphotransferase system (PTS), formed by a cascade of several proteins, couples the translocation and phosphorylation of specific sugars across cell membranes. The structure and thermal stability of the first protein (enzyme I, EI) of the PTS in Streptomyces coelicolor is studied by using far-UV circular dichroism (CD) and Fourier transform infrared spectroscopy (FTIR) at pH 7.0. The deconvolution of FTIR spectra indicates that the protein is mainly composed by a 35% of alpha-helical structure and 30% of beta-sheet. The thermal denaturation curves, as followed by both techniques, show only a midpoint at 330 K. This thermal denaturation behaviour is different to that observed in other members of the EI family.
Hurtado-Gómez
Estefanía
E
Instituto de Biología Molecular y Celular, Edificio Torregaitán, Universidad Miguel Hernández, Avda. del Ferrocarril s/n, 03202, Elche, Alicante, Spain.
Barrera
Francisco N
FN
Neira
José L
JL
D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism*; D002942:Circular Dichroism; D004795:Enzyme Stability; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D017550:Spectroscopy, Fourier Transform Infrared; D048372:Streptomyces coelicolor / Q000201:enzymology*; D013696:Temperature
D001426:Bacterial Proteins