Crystal Structure of Phosphoserine BlaC fromMycobacterium tuberculosisInactivated by Bis(Benzoyl) Phosphate.
Moural, T.W., White, D.S., Choy, C.J., Kang, C., Berkman, C.E.(2019) Int J Mol Sci 20
- PubMed: 31269656 
- DOI: https://doi.org/10.3390/ijms20133247
- Primary Citation of Related Structures:  
6N14 - PubMed Abstract: 
Mycobacterium tuberculosis , the pathogen responsible for tuberculosis (TB), is the leading cause of death from infectious disease worldwide. The class A serine β-lactamase BlaC confers Mycobacterium tuberculosis resistance to conventional β-lactam antibiotics. As the primary mechanism of bacterial resistance to β-lactam antibiotics, the expression of a β-lactamase by Mycobacterium tuberculosis results in hydrolysis of the β-lactam ring and deactivation of these antibiotics. In this study, we conducted protein X-ray crystallographic analysis of the inactivation of BlaC, upon exposure to the inhibitor bis(benzoyl) phosphate. Crystal structure data confirms that serine β-lactamase is phosphorylated at the catalytic serine residue (Ser-70) by this phosphate-based inactivator. This new crystallographic evidence suggests a mechanism for phosphorylation of BlaC inhibition by bis(benzoyl) phosphate over acylation. Additionally, we confirmed that bis(benzoyl) phosphate inactivated BlaC in a time-dependent manner.
Organizational Affiliation: 
Department of Chemistry, Washington State University, Pullman, WA 99164, USA.