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bioRxiv · 10.1101/2025.07.02.662783

The ParA-like ATPase PldP influences the TatA dynamics in Corynebacterium glutamicum

Abstract

In bacterial cells, precise localization of protein complexes is achieved by unique positioning systems. One of the examples of such positioning systems is the ParAB-parS which is responsible for plasmid and chromosome segregation. In Corynebacterium glutamicum, a parAB deletion results in cell division and growth defects, while deletion of an orphan ParA-like protein pldP results only in a moderate cell division phenotype. Having confirmed a basal ATPase activity of PldP, we aimed to explore if the {Delta}pldP-related phenotype could be a consequence of the mislocalized secreted proteins, as the loss of extracellular proteins involved in cell wall metabolism results in a similar phenotype characterized by disrupted separation of daughter cells. Putative peptidoglycan hydrolase Rv2525c from Mycobacterium tuberculosis and Rv2525c-like glycoside hydrolase-like domain-containing protein Cg0955 from C. glutamicum were previously shown to be transported outside of the cell by twin-arginine protein translocation machinery (Tat). Here, we found that although the deletion of pldP did not lead to the altered secretion of the putative hydrolase Cg0955 by the Tat system, it resulted in the reduction of the Tat dynamics. Our findings highlight the interplay between the ParA-like ATPase PldP and the Tat translocon and contribute to the studies of ParA-like proteins being essential in positioning various cargos in the bacterial cells. ImportancePrecise spatio-temporal localization of protein complexes within a bacterial cell is essential for the survival and proliferation of bacteria. ParA-like ATPases play a crucial role in protein positioning, as well as chromosome and plasmid segregation. Here, we characterize a novel ParA-like ATPase PldP in Corynebacterium glutamicum, a model organism for the cell biology of Mycobacteriales and a biotechnological workhorse. Deletion of pldP results in the cell division phenotypes and impacts the intracellular dynamics of TatA, a component of the twin-arginine protein transport. We suggest that the mislocalization of the Tat-secreted putative peptidoglycan hydrolase caused by the indirect influence of pldP deletion might account for the observed cell separation defect.

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Karnaukhova, E., Alwardt, D., Böhm, K., Weiss, M., Meyer, F. M., Giacomelli, G., Mehner-Breitfeld, D., Brüser, T., Bramkamp, M.. 2025-07-05. The ParA-like ATPase PldP influences the TatA dynamics in Corynebacterium glutamicum. https://doi.org/10.1101/2025.07.02.662783

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