Pyrazinamide resistance and mutations L19R, R140H, and E144K in Pyrazinamidase of Mycobacterium tuberculosis

Front. Bioeng. Biotechnol.

Kaushik

et al. 2019

Self Cite

Pyrazinamide (PZA) is one of the main FDA approved drugs to be used as the first line of defense against Mycobacterium Tuberculosis (MTB). It is activated into pyrazinoic acid (POA) via MTB's pncA gene-encoded pyrazinamidase (PZase). Mutations are most commonly responsible for PZA-resistance in nearly 70% of the resistant samples. In the present work, MTB positive samples were chosen for PZA drug susceptibility testing (DST) against critical concentration (100 ug/ml) of PZA. The resistant samples were subjected to pncA sequencing. As a result, 36 various mutations have been observed in the PZA resistant samples, uploaded to the NCBI (GeneBank accession no. MH461111). Here we report the mechanism of PZA resistance behind the three mutants (MTs), Asp12Ala, Pro54Leu, and His57Pro in comparison with the wild type (WT) through molecular dynamics simulation to unveil how these mutations affect the overall conformational stability. The post-simulation analyses revealed notable deviations as compared to the WT structure. Molecular docking studies of PZA with MTs and WT, pocket volume inspection and overall shape complementarity analysis confirmed the deleterious nature of these mutations and gave an insight into the mechanism behind PZA-resistance. These analyses provide vital information regarding MTB drug resistance and could be extremely useful in therapy management and overcoming its global burden.

Section: Drug Susceptibility Testing (Dst)mentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Structural Dynamics Behind Clinical Mutants of PncA-Asp12Ala, Pro54Leu, and His57Pro of Mycobacterium tuberculosis Associated With Pyrazinamide Resistance

Mehmood

Front. Bioeng. Biotechnol.

Kaushik

et al. 2019

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“…Although in our recent studies, the prevalence and mechanism of PZA resistance behind mutations in pncA and rpsA have been investigated, [19,[28][29][30][31] however, whole genome sequencing (WGS) is onestop method for epidemiological and molecular study of drug susceptibility testing. The potential clinical value and public health impact in the areas of DST for patient management and tracing of transmission chains for timely public health intervention have also been discussed [32][33][34].…”

Section: Introductionmentioning

confidence: 99%

Insight into the PZA resistance whole genome of Mycobacterium tuberculosis isolates from Khyber Pakhtunkhwa, Pakistan

Ali

et al. 2020

Preprint

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Background Tuberculosis (TB) is a global public health issue, getting worse due to emergence of resistance. Pyrazinamide (PZA) is first-line antimicrobial drugs used against non-replicated Mycobacterium tuberculosis (MTB). Data is scarce about whole genome sequencing of PZA resistance (PZA-R) in Khyber Pakhtunkhwa (KP) province of high burden country, Pakistan. In the current study we aimed to find the most common mutations in PZA-R MTB isolates in association with other candidate genes in a whole genome sequence (WGS). Samples were collected from TB suspects and drug susceptibility testing (DST) was performed according according to the WHO standards. The resistant samples were subjected for whole genome sequencing (WGS). The sequence data was through MTBseq and Total Genotyping Solution for Mycobacterium tuberculosis (TGS-TB). Metabolic model was analyzed, using RAST server. Results Among the three whole genome sequences, (NCBI BioProject Accession: PRJNA629298, PRJNA629388) 1997, 1162, and 2053 mutations including indel, was detected. Diverse variability has been detected in the membrane proteins PE and PPE, modulating the host immune response. Nine mutations in coding and promotor region have been detected in pncA with one novel (T-4C) variants. Mutations in the other drug candidate genes, KatG, rpoB have also been detected. Conclusion The metabolic model shows a distinct property. Diversity of variants has been detected in majority of MTB essential genes, functions from cell growth to cell signaling. The current study provides useful information, associated with geographic specific strains for biomarkers development and better management of drug resistance isolates.

“…Recently, a large number of PZA-resistance cases have been reported, affecting the latent TB treatment. In our recent study, we evaluated the mechanism behind PZA-resistance in RpsA and PncA, showing a significant effect of mutation in PncA on protein activity [39,40,41,42,43,44,45]. Due to the large number of PZA-resistance cases, the latent stage of TB may function as a reservoir for transmission, affecting the global TB end control program.…”

Section: Introductionmentioning

confidence: 99%

Marine Natural Products and Drug Resistance in Latent Tuberculosis

et al. 2019

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Pyrazinamide (PZA) is the only drug for the elimination of latent Mycobacterium tuberculosis (MTB) isolates. However, due to the increased number of PZA-resistance, the chances of the success of global TB elimination seems to be more prolonged. Recently, marine natural products (MNPs) as an anti-TB agent have received much attention, where some compounds extracted from marine sponge, Haliclona sp. exhibited strong activity under aerobic and hypoxic conditions. In this study, we screened articles from 1994 to 2019 related to marine natural products (MNPs) active against latent MTB isolates. The literature was also mined for the major regulators to map them in the form of a pathway under the dormant stage. Five compounds were found to be more suitable that may be applied as an alternative to PZA for the better management of resistance under latent stage. However, the mechanism of actions behind these compounds is largely unknown. Here, we also applied synthetic biology to analyze the major regulatory pathway under latent TB that might be used for the screening of selective inhibitors among marine natural products (MNPs). We identified key regulators of MTB under latent TB through extensive literature mining and mapped them in the form of regulatory pathway, where SigH is negatively regulated by RshA. PknB, RshA, SigH, and RNA polymerase (RNA-pol) are the major regulators involved in MTB survival under latent stage. Further studies are needed to screen MNPs active against the main regulators of dormant MTB isolates. To reduce the PZA resistance burden, understanding the regulatory pathways may help in selective targets of MNPs from marine natural sources.