Backbone assignment of crystalline E. coli maltose binding protein.

Area of Science:

• Biochemistry
• Biophysics
• Structural Biology

Background:

• The E.coli maltose binding protein (MBP) is a 42.5 kDa protein extensively used in biotechnology.
• Its size makes MBP a key model system for advancing solution Nuclear Magnetic Resonance (NMR) techniques for large biomolecules.

Purpose of the Study:

• To obtain near-complete backbone resonance assignments for MBP using solid-state NMR.
• To detail the methodology for sample preparation, NMR data acquisition, and spectral analysis.

Main Methods:

• Utilized 1H-detected solid-state NMR with fast magic-angle spinning (>100 kHz).
• Employed a uniformly 15N, 13C-labeled and fully protonated MBP sample.
• Collected data on an 800 MHz NMR spectrometer over approximately two weeks.

Main Results:

• Achieved virtually complete (~90%) backbone resonance assignments for MBP.
• Successfully prepared microcrystalline MBP samples suitable for solid-state NMR.
• Deposited chemical shift data to the Biological Magnetic Resonance Data Bank (BMRB) under accession number 50089.

Conclusions:

• Demonstrated the efficacy of high-speed solid-state NMR for large biomolecular targets like MBP.
• Provided a comprehensive methodological framework for future solid-state NMR studies on similar proteins.
• Facilitated further structural and dynamic investigations of MBP and related proteins.