Secondary structure of the phosphocarrier protein III sup Glc , a signal-transducing protein from Escherichia coli, determined by heteronuclear three-dimensional NMR spectroscopy

Journal Article · Mon Apr 15 00:00:00 EDT 1991 · Proceedings of the National Academy of Sciences of the United States of America; (United States)

DOI:https://doi.org/10.1073/pnas.88.8.3479· OSTI ID:6056996

Pelton, J G; Torchia, D A ^[1]; Meadow, N D; Wong, Cing-Yuen; Roseman, S ^[2]

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1. National Inst. of Health, Bethesda, MD (United States)
2. Johns Hopkins Univ., Baltimore, MD (United States)

III{sup Glc} is signal-transducing phosphocarrier protein of the phosphoenolpyruvate:glycose phosphotransferase system of Escherichia coli. The secondary structure of III{sup Glc} is determined by heteronuclear ({sup 15}N, {sup 13}C) three-dimensional NMR spectroscopy. Sequential, medium-range, and long-range nuclear Overhauser effects seen in NMR spectra are used to elucidate 11 antiparallel {beta}-strands and four helical segments. The medium-range nuclear Overhauser effect patterns suggest that the helices are either distorted {alpha}-helices or are of the 3{sub 10} class. The amino acids separating the active-site histidine residues (His{sup 75} and His{sup 90}) form two strands (Ala{sup 76}-Ser{sup 81} and Val{sup 85}-Phe{sup 91}) of a six-stranded antiparallel {beta}-sheet that brings His{sup 90} and His{sup 75} in close proximity. Sequence similarities in III{sup Glc} and several other sugar-transport proteins suggest that the histidine residues within these proteins may be arranged in a similar manner. The 18-residue N-terminal peptide that precedes {beta}-strand Thr{sup 19}-Ile{sup 22} in native III{sup Glc} is disordered and does not interact with the rest of the protein. Furthermore, removal of the N-terminal heptapeptide by a specific endopeptidase does not affect the structure of the remaining protein, thus explaining the phospho-acceptor activity of modified III{sup Glc} with the phospho-histidine-containing phosphocarrier protein of this system.

• OSTI ID: 6056996
• Journal Information: Proceedings of the National Academy of Sciences of the United States of America; (United States), Vol. 88:8; ISSN 0027-8424
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
MEMBRANE PROTEINS
NUCLEAR MAGNETIC RESONANCE
PHOSPHOENOLPYRUVATE
MEMBRANE TRANSPORT
CARBON 13
ESCHERICHIA COLI
NITROGEN 15
NMR SPECTRA
OVERHAUSER EFFECT
PHOSPHOTRANSFERASES
BACTERIA
CARBON ISOTOPES
ENZYMES
EVEN-ODD NUCLEI
ISOTOPES
LIGHT NUCLEI
MAGNETIC RESONANCE
MICROORGANISMS
NITROGEN ISOTOPES
NUCLEI
ODD-EVEN NUCLEI
ORGANIC COMPOUNDS
PHOSPHORUS-GROUP TRANSFERASES
PROTEINS
RESONANCE
SPECTRA
STABLE ISOTOPES
TRANSFERASES
550201* - Biochemistry- Tracer Techniques