Category Ranking

98%

Total Visits

921

Avg Visit Duration

2 minutes

Citations

20

Article Abstract

Increasing resistance against available orthosteric beta-lactamase inhibitors necessitates the search for novel and powerful inhibitor molecules. In this respect, allosteric inhibitors serve as attractive alternatives. Here, we examine the structural basis of inhibition in a hidden, druggable pocket in TEM-1 beta-lactamase. Based on crystallographic evidence that 6-cyclohexyl-1-hexyl-β-D-maltoside (CYMAL-6) binds to this site, first we determined the kinetic mechanism of inhibition by CYMAL-6. Activity measurements with CYMAL-6 showed that it competitively inhibits the wild type enzyme. Interestingly, it exhibits a steep dose-response curve with an IC50 of 100 μM. The IC50 value changes neither with different enzyme concentration nor with incubation of the enzyme with the inhibitor, showing that inhibition is not aggregation-based. The presence of the same concentrations of CYMAL-6 does not influence the activity of lactate dehydrogenase, further confirming the specificity of CYMAL-6 for TEM-1 beta-lactamase. Then, we identified compounds with high affinity to this allosteric site by virtual screening using Glide and Schrödinger Suite. Virtual screening performed with 500,000 drug like compounds from the ZINC database showed that top scoring compounds interact with the hydrophobic pocket that forms between H10 and H11 helices and with the catalytically important Arg244 residue through pi-cation interactions. Discovery of novel chemical scaffolds that target this allosteric site will pave the way for a new avenue in the design of new antimicrobials.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.jmgm.2018.06.007DOI Listing

Publication Analysis

Top Keywords

tem-1 beta-lactamase
8
allosteric site
8
virtual screening
8
cymal-6
5
targeting hidden
4
site
4
hidden site
4
site class
4
class beta-lactamases
4
beta-lactamases increasing
4

Similar Publications

Employing molecular dynamics (MD) simulation to study the formation of novel protein cryptic sites has attracted increasing interest in the field of drug discovery. One specific challenge in this area is finding a viable method to accurately identify and characterize cryptic site transitions from MD simulation results while minimizing the need for extensive human input. Since the formation of cryptic sites often involves significant conformational changes in the protein structure, a method capable of capturing and describing these dynamic pocket transitions with precision is essential.

View Article and Find Full Text PDF

Systems that perform continuous hypermutation of designated genes without compromising the integrity of the host genome can substantially accelerate the evolution of new or enhanced protein functions. We describe an orthogonal DNA replication system in based on the controlled expression of the replisome of bacteriophage T7 (T7-ORACLE). The system replicates circular plasmids that enable high transformation efficiencies and seamless integration into standard molecular biology workflows.

View Article and Find Full Text PDF

Bacterial populations can display different susceptibilities to antibiotics among individual cells, even though they originate from the same parent cell. This variability can lead to treatment failure and the emergence of resistant bacteria. Understanding the factors influencing this variability is crucial for developing effective antibiotic treatments.

View Article and Find Full Text PDF

The rapid evolution of extended-spectrum β-lactamases (ESBLs) represents a global health threat, undermining the efficacy of β-lactams, the most extensively used antibiotic class. To elucidate the evolutionary dynamics underlying β-lactam resistance, we constructed a comprehensive combinatorial mutant library comprising all 55,296 possible TEM-1 β-lactamase variants integrating 18 clinically observed mutations across 13 key residues. Over eight million empirical fitness measurements were obtained under selection pressure with both a native antibiotic substrate (ampicillin) and a novel antibiotic (aztreonam), establishing the largest experimentally determined fitness landscape for antibiotic resistance to date.

View Article and Find Full Text PDF

Comparative study of innovative computational methods for identifying cryptic pockets.

Drug Discov Today

August 2025

State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering, Ministry of Education, Center for Research and Development of Fine Chemicals, Guizhou University, Guiyang 550025, China. Electronic address: gefei

Cryptic pockets are crucial targets in drug discovery, yet their transient and concealed nature makes experimental detection challenging. Computational methods have proven highly effective for identifying and characterizing these elusive sites. Here, we systematically summarize and analyze state-of-the-art computational methods for cryptic pocket detection.

View Article and Find Full Text PDF