Mycobacterial resistance to zinc poisoning requires assembly of P-ATPase-containing membrane metal efflux platforms.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 35961955.
- Also identified by DOI 10.1038/s41467-022-32085-7 and PMC identifier 9374683.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
The human pathogen Mycobacterium tuberculosis requires a P<sub>1B</sub>-ATPase metal exporter, CtpC (Rv3270), for resistance to zinc poisoning. Here, we show that zinc resistance also depends on a chaperone-like protein, PacL1 (Rv3269). PacL1 contains a transmembrane domain, a cytoplasmic region with glutamine/alanine repeats and a C-terminal metal-binding motif (MBM). PacL1 binds Zn<sup>2+</sup>, but the MBM is required only at high zinc concentrations. PacL1 co-localizes with CtpC in dynamic foci in the mycobacterial plasma membrane, and the two proteins form high molecular weight complexes. Foci formation does not require flotillin nor the PacL1 MBM. However, deletion of the PacL1 Glu/Ala repeats leads to loss of CtpC and sensitivity to zinc. Genes pacL1 and ctpC appear to be in the same operon, and homologous gene pairs are found in the genomes of other bacteria. Furthermore, PacL1 colocalizes and functions redundantly with other PacL orthologs in M. tuberculosis. Overall, our results indicate that PacL proteins may act as scaffolds that assemble P-ATPase-containing metal efflux platforms mediating bacterial resistance to metal poisoning.
Medical subject headings
- Adenosine Triphosphatases
- Mycobacterium tuberculosis