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Biology subjects

Cleghorn, L. A. T.

Publications and source records attributed to Cleghorn, L. A. T..

2 recordsLinked to original sources

Identification and Evaluation of dibasic piperidines as novel cell wall inhibitors against Mycobacterium tuberculosis

Globally, Mycobacterium tuberculosis remains a significant disease burden. Although effective treatment regimens exist, drug resistance continues to emerge. This clinical resistance, combined with side effects and protracted treatment times from the current front-line therapies, means there is a need to identify novel agents to combat this disease. Here we report on a new chemical series, identified by whole-cell phenotypic growth inhibition screening that demonstrates significant activity across multiple media. Mode of action studies indicate that this series targets the same biological pathway as Ethambutol (EMB), a drug used in the current frontline treatment of tuberculosis. Screening selected analogues against clinical isolates, resistant to EMB, demonstrated differential sensitivity both across the molecules and against the different specific resistant mutations. The data obtained suggests that this series has potential to be developed into a viable, alternative to EMB. TOC figure O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=93 SRC="FIGDIR/small/702510v1_ufig1.gif" ALT="Figure 1"> View larger version (14K): org.highwire.dtl.DTLVardef@1a80c05org.highwire.dtl.DTLVardef@1ad3ce9org.highwire.dtl.DTLVardef@79fe79org.highwire.dtl.DTLVardef@131ed78_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

Peptidyl tRNA hydrolase is required for robust prolyl-tRNA turnover in Mycobacterium tuberculosis

Enzymes involved in rescuing stalled ribosomes and recycling translation machinery are ubiquitous in bacteria and required for growth. Peptidyl tRNA drop-off is a type of abortive translation that results in the release of a truncated peptide that is still bound to tRNA (peptidyl tRNA) into the cytoplasm. Peptidyl tRNA hydrolase (Pth) recycles the released tRNA by cleaving off the unfinished peptide and is essential in most bacterial species. We developed a sequencing-based strategy called Cu-tRNAseq to study the physiological role of Pth in Mycobacterium tuberculosis (Mtb). While most peptidyl tRNA species accumulated in a strain with impaired Pth expression, peptidyl prolyl-tRNA was particularly enriched, suggesting that Pth is required for robust peptidyl prolyl-tRNA turnover. Reducing Pth levels increased Mtbs susceptibility to tRNA synthetase inhibitors that are in development to treat tuberculosis (TB) and rendered this pathogen highly susceptible to macrolides, drugs that are ordinarily ineffective against Mtb. Collectively, our findings reveal the potency of Cu-tRNAseq for profiling peptidyl tRNAs and suggest that targeting Pth would open new therapeutic approaches for TB.

microbiology↗