5HVI

Crystal structure of TEM1 beta-lactamase

Summary for 5HVI

• Entry DOI: 10.2210/pdb5hvi/pdb
• Related: 5HW1 5HW5
• Descriptor: Beta-lactamase TEM (2 entities in total)
• Functional Keywords: hydrolase
• Biological source: Escherichia coli
• Total number of polymer chains: 4
• Total formula weight: 115647.62

Authors

Roose, B.W.,Dmochowski, I.J. (deposition date: 2016-01-28, release date: 2017-06-28, Last modification date: 2024-10-16)

Primary citation

Roose, B.W.,Zemerov, S.D.,Wang, Y.,Kasimova, M.A.,Carnevale, V.,Dmochowski, I.J.
A Structural Basis for129Xe Hyper-CEST Signal in TEM-1 beta-Lactamase.
Chemphyschem, 2018

PubMed Abstract: Genetically encoded (GE) contrast agents detectable by magnetic resonance imaging (MRI) enable non-invasive visualization of gene expression and cell proliferation at virtually unlimited penetration depths. Using hyperpolarized Xe in combination with chemical exchange saturation transfer, an MR contrast approach known as hyper-CEST, enables ultrasensitive protein detection and biomolecular imaging. GE MRI contrast agents developed to date include nanoscale proteinaceous gas vesicles as well as the monomeric bacterial proteins TEM-1 β-lactamase (bla) and maltose binding protein (MBP). To improve understanding of hyper-CEST NMR with proteins, structural and computational studies were performed to further characterize the Xe-bla interaction. X-ray crystallography validated the location of a high-occupancy Xe binding site predicted by MD simulations, and mutagenesis experiments confirmed this Xe site as the origin of the observed CEST contrast. Structural studies and MD simulations with representative bla mutants offered additional insight regarding the relationship between local protein structure and CEST contrast.

PubMed: 30151973
DOI: 10.1002/cphc.201800624

Experimental method

X-RAY DIFFRACTION (1.64 Å)