A significant decrease in melting temperature (BlaC T M 60☌, S130A T M 50☌, and S130G T M 45☌), kinetic instability at higher temperature, and comparative dynamic instability correlate the fact that resistance to beta-lactam/beta-lactamase inhibitor combinations will likely not arise from the structural alteration of BlaC, therefore establishing confidence that this therapeutic modality can be potentially applied as a part of a successful treatment regimen against M. To understand the molecular reasoning behind the unavailability of such mutation in real life, we have used circular dichroism (CD) spectroscopy, differential scanning calorimetry (DSC), molecular dynamics (MD) simulation, and stability-based enzyme activity to compare the stability and dynamic behaviors of native and S130G/A mutant form of BlaC. The study involving steady state, inhibition kinetics, and fluorescence microscopy shows the emergence of resistance against MBIs to the mutants expressing S130G and S130A. tuberculosis draws our attention to build laboratory mutants of S130G and S130A of BlaC. The absence of clinical evidence of S130G conversion in M. Alterations at Ser130 in conserved SDN loop confer resistance to mechanism-based inhibitors (MBIs) commonly observed in various clinical isolates. BlaC belongs to Ambler class A, which is generally susceptible to the beta-lactamase inhibitors currently used in clinics: tazobactam, sulbactam, and clavulanate. Recently, BlaC, the principal beta-lactamase of Mycobacterium tuberculosis, was recognized as a potential therapeutic target. The emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) tuberculosis calls for an immediate search for novel treatment strategies. 5Centre for Nanotechnology, Indian Institute of Technology Roorkee, Roorkee, India.4Department of Surgical Biotechnology, University College London, London, United Kingdom.3Academy of Scientific and Innovative Research, Ghaziabad, India.2Biochemistry and BIotechnology Area, Material Resource Efficiency Division, CSIR-Indian Institute of Petroleum, Dehradun, India.

1Department of Biosciences and Bioengineering, Indian Institute of Technology Roorkee, Roorkee, India.Sourya Bhattacharya 1, Vivek Junghare 1, Niteesh Kumar Pandey 1, Subhecchha Baidya 1, Harsha Agarwal 1, Neeladrisingha Das 1, Ayan Banerjee 2,3, Debashish Ghosh 2,3, Partha Roy 1, Hirak K.

Analize stoichiometry chemdraw ultra 12