Authors
Cátia Silveiro, Mariana Marques, Francisco Olivença, David Pires, Elsa Anes, Maria João Catalão
Published in
Scientific reports. Jun 23, 2026. Epub Jun 23, 2026.
Abstract
The high mortality associated with tuberculosis (TB), alongside the lack of efficient therapeutics against emerging multidrug-resistant Mycobacterium tuberculosis (Mtb) strains, emphasizes the need for novel antitubercular targets. Mycobacterial peptidoglycan (PG), displaying characteristic modifications comprising the amidation of D-iso-glutamate (D-iGlu) and the N-glycolylation of muramic acid, is therefore a promising therapeutic target. The genes encoding the enzymes mediating these modifications (murT/gatD and namH) were silenced in Mtb using CRISPR interference (CRISPRi) to investigate their impact on β-lactam susceptibility and host immune responses. First, qRT-PCR confirmed successful target mRNA knockdown and phenotyping assays corroborated the essentiality of D-iGlu amidation for mycobacterial growth, in contrast to muramic acid N-glycolylation. The susceptibility assays demonstrated that both PG modifications promote β-lactam resistance. Indeed, we observed reductions in the minimum fractional inhibitory concentration index (FICImin) value for AMX/MEM + CLA and EMB combinations following the depletion of both PG modifications. Furthermore, D-iGlu amidation was found to promote Mtb fitness within THP-1-derived macrophages 6 days post-infection. Infection with MurT/GatD-depleted Mtb was associated with increased IL-1β and decreased IL-10, whereas NamH depletion was linked to increased IL-1β and IL-10 levels. Altogether, our findings unveiled the potential of targeting these PG modifications for the development of innovative therapeutic regimens against TB.
PMID:
42337014
Bibliographic data and abstract were imported from PubMed on 24 Jun 2026.
Read full publication at:
Please sign in
to see all details.
Advertisement
Stats
- Recommendations n/a n/a positive of 0 vote(s)
- Views 2
- Comments 0