The peptidoglycan-binding domain of a mycobacterial prophage-encoded LysinB reveals diverse approaches for domain conservation in hydrolases.

Mycobacteriophage-encoded LysinB enzymes target mycolyl ester linkages in mycolyl-arabinogalactan-peptidoglycan of mycobacterium hosts and generally exhibit a globular architecture. Here, we present the structural and functional characterization of a novel Mycobacterium fortuitum prophage-encoded modular LysinB (LysinB_MF), which contains the α/β hydrolase domain and a distinct peptidoglycan-binding domain (PGBD). The enzyme's active site features the conserved Ser-Asp-His catalytic triad common to esterases and forms a funnel-like topology.

Genomic analysis of five new mycobacteriophages belonging to the F, G, K, and P clusters.

Unlabelled: Mycobacterial infections are accountable for some of the most challenging diseases to treat in both humans and veterinary medicine, particularly with the increasing prevalence of multidrug-resistant (MDR) species. Bacteriophages (phages) are being actively investigated as a promising alternative to antibiotic therapy and mycobacteriophages, phages that infect mycobacteria, have recently been demonstrated to be effective candidates in phage therapy. Therefore, discovery and genomic characterisation of diverse phages capable of infecting and killing pathogenic mycobacteria are crucial steps in both monophage therapy and multi-phage therapy, where two or more phages are used in combination.

Dry powder Inhalation of lytic mycobacteriophages for adjunct therapy in a mouse model of infection with Mycobacteriumtuberculosis.

Inhaled therapy of tuberculosis (TB) by a Dry Powder Inhalation (DPI) comprising mycobacteriophage D29 and TM4 was non-inferior to oral anti-tuberculosis therapy (ATT) with isoniazid and rifampicin in a mouse model of infection with Mycobacterium tuberculosis (Mtb). No pharmaceutical phage product of mycobacteriophages is approved for large-scale production. We scaled up preparation and downstream processing of phages, developed DPI formulations, and established methods for determining identity, purity, assay, stability, and critical quality attributes (CQA).

Integrated analysis of cell cycle and p53 signaling pathways related genes in breast, colorectal, lung, and pancreatic cancers: implications for prognosis and drug sensitivity for therapeutic potential.

Cancer, a leading cause of death worldwide, is projected to increase by 76.6% in new cases and 89.7% in mortality by 2050 (WHO 2022).

Discovery and characterization of a novel LysinB from F2 sub-cluster mycobacteriophage RitSun.

The escalating antibiotic resistance in mycobacterial species poses a significant threat globally, necessitating an urgent need to find alternative solutions. Bacteriophage-derived endolysins, which facilitate phage progeny release by attacking bacterial cell walls, present promising antibacterial candidates due to their rapid lytic action, high specificity and low risk of resistance development. In mycobacteria, owing to the complex, hydrophobic cell wall, mycobacteriophages usually synthesize two endolysins: LysinA, which hydrolyzes peptidoglycan; LysinB, which delinks mycolic acid-containing outer membrane and arabinogalactan, releasing free mycolic acid.

Mycobacteriophages: therapeutic approach for mycobacterial infections.

Tuberculosis (TB) is a significant global health threat, and cases of infection with non-tuberculous mycobacteria (NTM) causing lung disease (NTM-LD) are rising. Bacteriophages and their gene products have garnered interest as potential therapeutic options for bacterial infections. Here, we have compiled information on bacteriophages and their products that can kill Mycobacterium tuberculosis or NTM.

Insights into the genomic features and lifestyle of B1 subcluster mycobacteriophages.

Bacteriophages infecting Mycobacterium smegmatis mc155 are numerous and, hence, are classified into clusters based on nucleotide sequence similarity. Analyzing phages belonging to clusters/subclusters can help gain deeper insights into their biological features and potential therapeutic applications. In this study, for genomic characterization of B1 subcluster mycobacteriophages, a framework of online tools was developed, which enabled functional annotation of about 55% of the previously deemed hypothetical proteins in B1 phages.

Unlocking prophage potential: and experimental analysis of a novel LysinB containing a peptidoglycan-binding domain.

Endolysins are highly evolved bacteriophage-encoded lytic enzymes produced to damage the bacterial cell wall for phage progeny release. They offer promising potential as highly specific lytic proteins with a low chance of bacterial resistance. The diversity in lysin sequences and domain organization can be staggering.

Identification of perturbed pathways rendering susceptibility to tuberculosis in type 2 diabetes mellitus patients using BioNSi simulation of integrated networks of implicated human genes.

In type 2 diabetes mellitus (T2DM) patients, chronic hyperglycemia and inflammation underlie susceptibility to tuberculosis (TB) and result in poor TB control. Here, an integrative pathway-based approach is used to investigate perturbed pathways in T2DM patients that render susceptibility to TB. We obtained 36 genes implicated in type 2 diabetes-associated tuberculosis (T2DMTB) from the literature.

Functional characterization of a DNA-dependent AAA ATPase in a F-cluster mycobacteriophage.

Mycobacteriophages are viruses of Mycobacterium spp. with promising diagnostic and therapeutic potential. Phage genome exploration and characterization of their proteomes are essential to gaining a better understanding of their role in phage biology.

Alternative Treatment Strategies for Secondary Bacterial and Fungal Infections Associated with COVID-19.

Antimicrobials are essential for combating infectious diseases. However, an increase in resistance to them is a major cause of concern. The empirical use of drugs in managing COVID-19 and the associated secondary infections have further exacerbated the problem of antimicrobial resistance.

prediction of natural compounds as potential multi-target inhibitors of structural proteins of SARS-CoV-2.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a colossal loss to human health and lives and has deeply impacted socio-economic growth. Remarkable efforts have been made by the scientific community in containing the virus by successful development of vaccines and diagnostic kits. Initiatives towards drug repurposing and discovery have also been undertaken.

Computational identification and characterization of antigenic properties of Rv3899c of Mycobacterium tuberculosis and its interaction with human leukocyte antigen (HLA).

A rise in drug-resistant tuberculosis (TB) cases demands continued efforts towards the discovery and development of drugs and vaccines. Secretory proteins of Mycobacterium tuberculosis (H37Rv) are frequently studied for their antigenicity and their scope as protein subunit vaccines requires further analysis. In this study, Rv3899c of H37Rv emerges as a potential vaccine candidate on its evaluation by several bioinformatics tools.

Screening of compound library identifies novel inhibitors against the MurA enzyme of Escherichia coli.

Bacterial cell has always been an attractive target for anti-infective drug discovery. MurA (UDP-N-acetylglucosamine enolpyruvyl transferase) enzyme of Escherichia coli (E.coli) is crucial for peptidoglycan biosynthetic pathway, as it is involved in the early stages of bacterial cell wall biosynthesis.

Design and Synthesis of Various 5'-Deoxy-5'-(4-Substituted-1,2,3-Triazol-1-yl)-Uridine Analogues as Inhibitors of Mur Ligases.

The synthesis of hitherto unknown 5'-deoxy-5'-(4-substituted-1,2,3-triazol-1-yl)-uridine and its evaluation, through an one-pot screening assay, against MurA-F enzymes involved in (Mtb), are described. Starting from UDP--acetylmuramic acid (UDP-MurNAc), the natural substrate involved in the peptidoglycan biosynthesis, our strategy was to substitute the diphosphate group of UDP-MurNAc by a 1,2,3-triazolo spacer under copper-catalyzed azide-alkyne cycloaddition conditions. The structure-activity relationship was discussed and among the 23 novel compounds developed, -acetylglucosamine analogues and emerged as the best inhibitors against the Mtb MurA-F enzymes reconstruction pathway with an inhibitory effect of 56% and 50%, respectively, at 100 μM.

Characterization and genome analysis of B1 sub-cluster mycobacteriophage PDRPxv.

Mycobacteriophages are viruses specific to mycobacteria that have gained attention as alternative therapeutic strategies for treating antibiotic-resistant infections. Mycobacteriophages are highly diverse and have been grouped into 29 clusters, 71 sub-clusters and 10 singletons based on the genome sequence. Here, we annotate the genome of PDRPxv, a lytic mycobacteriophage isolated from New Delhi; it belongs to the Siphoviridae family as determined by transmission electron microscopy.

Screening of Antitubercular Compound Library Identifies Inhibitors of Mur Enzymes in .

The rapid rise in the emergence of multidrug-resistant (MDR) and extensively drug-resistant (XDR) strains of (Mtb) mandates the discovery of novel tuberculosis (TB) drugs. Mur enzymes, which are identified as essential proteins in Mtb and catalyze the cytoplasmic steps in the peptidoglycan biosynthetic pathway, are considered potential drug targets. However, none of the clinical drugs have yet been developed against these enzymes.

Repurposing of FDA-approved drugs to target MurB and MurE enzymes in .

Tuberculosis (TB), caused by (Mtb) is one amongst the top 10 causes of death worldwide. The growing rise in antibiotic resistance compounded with slow and expensive drug discovery has further aggravated the situation. 'Drug repurposing' is a promising approach where known drugs are examined for a new indication.

Isolation and characterization of bacteriophages from India, with lytic activity against Mycobacterium tuberculosis.

Bacteriophages are being considered as a promising natural resource for the development of alternative strategies against mycobacterial diseases, especially in the context of the wide-spread occurrence of drug resistance among the clinical isolates of Mycobacterium tuberculosis. However, there is not much information documented on mycobacteriophages from India. Here, we report the isolation of 17 mycobacteriophages using Mycobacterium smegmatis as the bacterial host, where 9 phages also lyse M.

Crystal structure of UDP-N-acetylglucosamine-enolpyruvate reductase (MurB) from Mycobacterium tuberculosis.

The biosynthesis of UDP-N-acetylmuramic acid (UDP-MurNAc) by reduction of UDP-N-acetylglucosamine-enolpyruvate (UDP-GlcNAc-EP) in an NADPH and FAD-dependent reaction in bacteria is one of the key steps in peptidoglycan biosynthesis catalyzed by UDP-N-acetylglucosamine-enolpyruvate reductase (MurB). Here, we present the crystal structure of Mycobacterium tuberculosis MurB (MtbMurB) with FAD as the prosthetic group at 2.0Å resolution.

Development of a one-pot assay for screening and identification of Mur pathway inhibitors in Mycobacterium tuberculosis.

The cell wall of Mycobacterium tuberculosis (Mtb) consists of peptidoglycan, arabinogalactan and mycolic acids. The cytoplasmic steps in the peptidoglycan biosynthetic pathway, catalyzed by the Mur (A-F) enzymes, involve the synthesis of UDP-n-acetylmuramyl pentapeptide, a key precursor molecule required for the formation of the peptidoglycan monomeric building blocks. Mur enzymes are indispensable for cell integrity and their lack of counterparts in eukaryotes suggests them to be promising Mtb drug targets.