1H, 15N and 13C NMR Assignments, Secondary Structure and Overall Topology of the Escherichia Coli GlgS Protein

Eur J Biochem. 1997 Jun 1;246(2):301-10. doi: 10.1111/j.1432-1033.1997.t01-1-00301.x.


GlgS is a 7892-Da protein which is involved in glycogen biosynthesis in bacteria. We report the 1H, 15N and 13C NMR assignments of the backbone and side-chain resonances at 25 degrees C and pH 6.7 from two-dimensional homonuclear and three-dimensional heteronuclear NMR experiments. The secondary structure of the protein was determined using sequential and medium-range NOE correlations, vicinal 3J(NH-H alpha) coupling values and amide proton exchange rates. The secondary structure obtained is consistent with the secondary chemical shifts of 1H alpha, 13C alpha and 13C = O. It was found that the secondary structure of GlgS comprises two amphipathic helices (Asn10-Met21 and Glu39-Arg60), one short highly hydrophobic helix (Ile30-Val33), a short extended beta-strand-like fragment (Arg26-Asp29) and two type I beta-turns (His22-Gly25 and Thr34-Met37). An overall topology of GlgS is suggested based on long-range NOEs. The elements of secondary structure form a sandwich in which the beta-strand and the short hydrophobic helix are positioned between the two amphipathic helices.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / chemistry*
  • Bacterial Proteins / isolation & purification
  • Carbon Isotopes
  • Chromatography, Gel
  • Escherichia coli / chemistry*
  • Escherichia coli Proteins*
  • Magnetic Resonance Spectroscopy
  • Mass Spectrometry
  • Molecular Sequence Data
  • Nitrogen Isotopes
  • Protein Structure, Secondary
  • Protons
  • Recombinant Proteins / chemistry
  • Recombinant Proteins / isolation & purification


  • Bacterial Proteins
  • Carbon Isotopes
  • Escherichia coli Proteins
  • GlgS protein, E coli
  • Nitrogen Isotopes
  • Protons
  • Recombinant Proteins