Proteomic analysis of Mycobacterium tuberculosis lacking a putative short-chain dehydrogenase (Rv0148)

Abstract

Mycobacterium tuberculosis (Mtb) is an intracellular pathogen that survives in host cells by resisting hostile antimicrobial defenses. However, the molecules and mechanisms that contribute to Mtbs intracellular survival are not fully understood. We have previously reported that Rv0148, a putative short-chain dehydrogenase/reductase, plays a significant role in Mtb stress response and virulence in in vitro and in vivo models. To further understand the role of Rv0148 in regulating global functions of Mtb, we performed comparative proteomic analysis between pathogenic wild-type (WT) and{Delta} rv0148 mutant strains. Our mass spectrometry-based proteomics approach identified a total of 738 and 469 proteins, respectively, in the WT and{Delta} rv0148 mutant, with distinct expression patterns. Gene Ontology analysis revealed significant enrichment of proteins involved in biological processes such as resistant to host immune response and protein homeostasis in{Delta} rv0148 mutant, while peptidoglycan biosynthesis and ribosomal metabolism pathways were downregulated. Further network analysis revealed dysregulation of proteins involved in bacterial stress response, cell wall components, ribosomal and secretory proteins, suggesting impaired translational machinery in{Delta} rv0148 mutant. Functional categorization of differentially regulated proteins in{Delta} rv0148 mutant showed broad reprogramming in intermediary metabolism, stress adaptation, and secretion. These findings indicate that Rv0148 functions as a global regulatory node, which influences remodeling of cell wall components and bacterial physiology, potentially balancing survival and stress adaptation mechanisms in Mtb. IMPORTANCEMycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is a notorious pathogen that can resist the hostile host environment to survive intracellularly and to cause disease. However, the molecular determinants that contribute to Mtbs adaptation to resist the host-imposed stress conditions are not fully understood. Previous in vitro and in vivo studies have shown that Rv0148, a putative short-chain dehydrogenase/reductase, is involved in Mtb stress response and virulence. In this study, the genome wide proteomic profile of Mtb mutant lacking Rv0148 ({Delta}rv0148) was investigated. Compared to the wild type Mtb strain, striking changes in proteome profile of{Delta} rv0148 mutant was noted. Proteins involved in the ESX secretion system, stress response, ribosomal protein metabolism and cell wall components were significantly affected in the{Delta} rv0148 mutant. The impact of these changes in biological functions that link Rv0148s role in Mtbs adaptation to stress conditions is discussed.