Structural studies of bacterial transcriptional regulatory proteins by multidimensional heteronuclear NMR

Thesis/Dissertation · Wed Feb 01 04:00:00 EST 1995

DOI:https://doi.org/10.2172/67729· OSTI ID:67729

Volkman, Brian Finley ^[1]

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1. Univ. of California, Berkeley, CA (United States)

Nuclear magnetic resonance spectroscopy was used to elucidate detailed structural information for peptide and protein molecules. A small peptide was designed and synthesized, and its three-dimensional structure was calculated using distance information derived from two-dimensional NMR measurements. The peptide was used to induce antibodies in mice, and the cross-reactivity of the antibodies with a related protein was analyzed with enzyme-linked immunosorbent assays. Two proteins which are involved in regulation of transcription in bacteria were also studied. The ferric uptake regulation (Fur) protein is a metal-dependent repressor which controls iron uptake in bacteria. Two- and three-dimensional NMR techniques, coupled with uniform and selective isotope labeling allowed the nearly complete assignment of the resonances of the metal-binding domain of the Fur protein. NTRC is a transcriptional enhancer binding protein whose N-terminal domain is a "receiver domain" in the family of "two-component" regulatory systems. Phosphorylation of the N-terminal domain of NTRC activates the initiation of transcription of aeries encoding proteins involved in nitrogen regulation. Three- and four-dimensional NMR spectroscopy methods have been used to complete the resonance assignments and determine the solution structure of the N-terminal receiver domain of the NTRC protein. Comparison of the solution structure of the NTRC receiver domain with the crystal structures of the homologous protein CheY reveals a very similar fold, with the only significant difference being the position of helix 4 relative to the rest of the protein. The determination of the structure of the NTRC receiver domain is the first step toward understanding a mechanism of signal transduction which is common to many bacterial regulatory systems.

• Research Organization: California Univ., Berkeley, CA (United States). Dept. of Chemistry; Lawrence Berkeley Lab., CA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC03-76SF00098
• OSTI ID: 67729
• Report Number(s): LBL--36921; ON: DE95011259
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
BACTERIA
MOLECULAR STRUCTURE
NUCLEAR MAGNETIC RESONANCE
PROTEINS
TRANSCRIPTION
TRANSCRIPTION FACTORS