Antibiotics. Targeting DnaN for tuberculosis therapy using novel griselimycins.

Area of Science:

• Microbiology
• Molecular Biology
• Drug Discovery

Background:

• Tuberculosis (TB) remains a global health challenge, exacerbated by the rise of multidrug-resistant Mycobacterium tuberculosis.
• Existing TB therapies, while effective, face challenges with resistance and treatment duration.
• Novel antimicrobial agents targeting essential bacterial processes are urgently needed.

Purpose of the Study:

• To evaluate the efficacy of novel, optimized griselimycin derivatives against Mycobacterium tuberculosis.
• To elucidate the mechanism of action and resistance of these new compounds.
• To assess the translational potential of griselimycins as a new class of anti-TB drugs.

Main Methods:

• In vitro and in vivo testing of griselimycin derivatives against M. tuberculosis strains.
• Investigation of the molecular target using biochemical assays.
• Analysis of resistance mechanisms through genetic studies, including DNA sequencing and gene amplification analysis.

Main Results:

• Optimized griselimycin derivatives demonstrated high activity against M. tuberculosis in both laboratory and animal models.
• The compounds inhibit the essential DNA polymerase sliding clamp, DnaN.
• Low-frequency resistance was linked to amplification of the dnaN gene and the origin of replication (ori).

Conclusions:

• Griselimycin derivatives represent a promising new class of antibiotics with high translational potential for treating tuberculosis.
• DnaN is validated as a crucial antimicrobial target for developing new anti-TB therapies.
• The study provides insights into antibiotic-induced gene amplification as a resistance mechanism.