1
|
Singh BK, Singha M, Basak S, Biswas R, Das AK, Basak A. Fluorescently labelled thioacetazone for detecting the interaction with Mycobacterium dehydratases HadAB and HadBC. Org Biomol Chem 2022; 20:1444-1452. [PMID: 35084426 DOI: 10.1039/d1ob02080c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Thioacetazone (TAC) used to be a highly affordable, bacteriostatic anti-TB drug but its use has now been restricted, owing to severe side-effects and the frequent appearance of the TAC resistant M. tuberculosis strains. In order to develop new TAC analogues with fewer side-effects, its target enzymes need to be firmly established. It is now hypothesized that TAC, after being activated by a monooxygenase EthA, binds to the dehydratase complex HadAB that finally leads to a covalent modification of HadA, the main partner involved in dehydration. Another dehydratase enzyme, namely HadC in the HadBC complex, is also thought to be a possible target for TAC, for which definitive evidence is lacking. Herein, using a recently exploited azido naphthalimide template attached to thioacetazone and adopting a photo-affinity based labelling technique, coupled with electrophoresis and in-gel visualization, we have successfully demonstrated the involvement of these enzymes including HadBC along with a possible participation of an alternate mycobacterial monooxygenase MymA. In silico studies also revealed strong interactions between the TAC-probe and the concerned enzymes.
Collapse
Affiliation(s)
- Bina K Singh
- School of Bioscience, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Monisha Singha
- Department of Chemistry, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Shyam Basak
- Department of Chemistry, Indian Institute of Technology, Kharagpur, 721302, India.
| | - Rupam Biswas
- Department of Biotechnology, Indian Institute of Technology, Kharagpur, 721302, India
| | - Amit K Das
- School of Bioscience, Indian Institute of Technology, Kharagpur, 721302, India. .,Department of Biotechnology, Indian Institute of Technology, Kharagpur, 721302, India
| | - Amit Basak
- School of Bioscience, Indian Institute of Technology, Kharagpur, 721302, India. .,Department of Chemistry, Indian Institute of Technology, Kharagpur, 721302, India.
| |
Collapse
|
2
|
Bahr G, González LJ, Vila AJ. Metallo-β-lactamases and a tug-of-war for the available zinc at the host-pathogen interface. Curr Opin Chem Biol 2022; 66:102103. [PMID: 34864439 PMCID: PMC8860843 DOI: 10.1016/j.cbpa.2021.102103] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2021] [Revised: 10/16/2021] [Accepted: 10/28/2021] [Indexed: 02/03/2023]
Abstract
Metallo-β-lactamases (MBLs) are zinc-dependent hydrolases that inactivate virtually all β-lactam antibiotics. The expression of MBLs by Gram-negative bacteria severely limits the therapeutic options to treat infections. MBLs bind the essential metal ions in the bacterial periplasm, and their activity is challenged upon the zinc starvation conditions elicited by the native immune response. Metal depletion compromises both the enzyme activity and stability in the periplasm, impacting on the resistance profile in vivo. Thus, novel inhibitory approaches involve the use of chelating agents or metal-based drugs that displace the native metal ion. However, newer MBL variants incorporate mutations that improve their metal binding abilities or stabilize the metal-depleted form, revealing that metal starvation is a driving force acting on MBL evolution. Future challenges require addressing the gap between in cell and in vitro studies, dissecting the mechanism for MBL metalation and determining the metal content in situ.
Collapse
Affiliation(s)
- Guillermo Bahr
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET-UNR), S2000EXF Rosario, Argentina; Área Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, S2002LRK Rosario, Argentina
| | - Lisandro J González
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET-UNR), S2000EXF Rosario, Argentina; Área Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, S2002LRK Rosario, Argentina
| | - Alejandro J Vila
- Instituto de Biología Molecular y Celular de Rosario (IBR, CONICET-UNR), S2000EXF Rosario, Argentina; Área Biofísica, Facultad de Ciencias Bioquímicas y Farmacéuticas, Universidad Nacional de Rosario, S2002LRK Rosario, Argentina.
| |
Collapse
|
3
|
Mehta R, Rivera DD, Reilley DJ, Tan D, Thomas PW, Hinojosa A, Stewart AC, Cheng Z, Thomas CA, Crowder MW, Alexandrova AN, Fast W, Que EL. Visualizing the Dynamic Metalation State of New Delhi Metallo-β-lactamase-1 in Bacteria Using a Reversible Fluorescent Probe. J Am Chem Soc 2021; 143:8314-8323. [PMID: 34038127 DOI: 10.1021/jacs.1c00290] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
New Delhi metallo-β-lactamase (NDM) grants resistance to a broad spectrum of β-lactam antibiotics, including last-resort carbapenems, and is emerging as a global antibiotic resistance threat. Limited zinc availability adversely impacts the ability of NDM-1 to provide resistance, but a number of clinical variants have emerged that are more resistant to zinc scarcity (e.g., NDM-15). To provide a novel tool to better study metal ion sequestration in host-pathogen interactions, we describe the development of a fluorescent probe that reports on the dynamic metalation state of NDM within Escherichia coli. The thiol-containing probe selectively coordinates the dizinc metal cluster of NDM and results in a 17-fold increase in fluorescence intensity. Reversible binding enables competition and time-dependent studies that reveal fluorescence changes used to detect enzyme localization, substrate and inhibitor engagement, and changes to metalation state through the imaging of live E. coli using confocal microscopy. NDM-1 is shown to be susceptible to demetalation by intracellular and extracellular metal chelators in a live-cell model of zinc dyshomeostasis, whereas the NDM-15 metalation state is shown to be more resistant to zinc flux. The development of this reversible turn-on fluorescent probe for the metalation state of NDM provides a new tool for monitoring the impact of metal ion sequestration by host defense mechanisms and for detecting inhibitor-target engagement during the development of therapeutics to counter this resistance determinant.
Collapse
Affiliation(s)
- Radhika Mehta
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712, United States
| | - Dann D Rivera
- Division of Chemical Biology & Medicinal Chemistry, College of Pharmacy, University of Texas, Austin, Texas 78712, United States
| | - David J Reilley
- Department of Chemistry and Biochemistry, University of California-Los Angeles, 607 Charles E. Young Drive, Los Angeles, California 90095-1569, United States
| | - Dominique Tan
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712, United States
| | - Pei W Thomas
- Division of Chemical Biology & Medicinal Chemistry, College of Pharmacy, University of Texas, Austin, Texas 78712, United States
| | - Abigail Hinojosa
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712, United States
| | - Alesha C Stewart
- Division of Chemical Biology & Medicinal Chemistry, College of Pharmacy, University of Texas, Austin, Texas 78712, United States
| | - Zishuo Cheng
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Caitlyn A Thomas
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Michael W Crowder
- Department of Chemistry and Biochemistry, Miami University, Oxford, Ohio 45056, United States
| | - Anastassia N Alexandrova
- Department of Chemistry and Biochemistry, University of California-Los Angeles, 607 Charles E. Young Drive, Los Angeles, California 90095-1569, United States
| | - Walter Fast
- Division of Chemical Biology & Medicinal Chemistry, College of Pharmacy, University of Texas, Austin, Texas 78712, United States
| | - Emily L Que
- Department of Chemistry, University of Texas at Austin, 105 East 24th Street Stop A5300, Austin, Texas 78712, United States
| |
Collapse
|
4
|
Singha M, Roy S, Moirangthem R, Das AK, Basak A. Naphthalimide-Based Template for Inhibitor Screening via Cross-Linking and In-Gel Fluorescence: A Case Study against HCA II. ACS OMEGA 2019; 4:11914-11920. [PMID: 31460302 PMCID: PMC6681978 DOI: 10.1021/acsomega.9b01044] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/12/2019] [Accepted: 06/26/2019] [Indexed: 06/10/2023]
Abstract
We describe a rapid electrophoresis-based method for profiling of carbonic anhydrase inhibitors. In addition to the pharmacophore moiety intended for reversible interaction with a target enzyme, a fluorescent template with a built-in azide group for photoaffinity labeling is also included as a part of the inhibitor design. Following incubation and irradiation, gel electrophoresis with visualization under UV allows assessment of the efficiency of cross-linking. The relative efficiency of cross-linking of various probes can be regarded as a reflection of their inhibition potencies, an assumption supported by the trend in their IC50/K i values. The method has the advantage of being applicable to impure enzyme preparations and also can be used to screen several inhibitors including their promiscuity in parallel in a short time as has been currently demonstrated with HCA II.
Collapse
Affiliation(s)
- Monisha Singha
- Department
of Chemistry, School of Bioscience, and Department of Biotechnology Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Sayantani Roy
- Department
of Chemistry, School of Bioscience, and Department of Biotechnology Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Ravina Moirangthem
- Department
of Chemistry, School of Bioscience, and Department of Biotechnology Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Amit K. Das
- Department
of Chemistry, School of Bioscience, and Department of Biotechnology Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Amit Basak
- Department
of Chemistry, School of Bioscience, and Department of Biotechnology Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| |
Collapse
|