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bioRxiv · 10.1101/2022.03.07.483215

An actin-like filament from Clostridium botulinum exhibits a novel mechanism of filament dynamics

Koh, A.·Ali, S.·Popp, D.·Tanaka, K.·Kitaoku, Y.·Miyazaki, N.·Kenji, I.·Mitsuoka, K.·Robinson, R. C.·Narita, A.
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Abstract

Here, we report the discovery of a ParM protein from Clostridium botulinum (CBgs-ParM), which forms a double-stranded polar filament. CBgs-ParM shares many similarities in its basic filament architecture with actin, however, Pi release after nucleotide hydrolysis induces a large lateral strand shift of ~2.5 nm. We identified the ParR (CBgs-ParR) that acts as a nucleation factor in the initial stage of polymerization, similar to ParR from Escherichia coli plasmid R1. CBgs-ParR also functions as a depolymerization factor, probably by recognizing the structural change in the CBgs-ParM filament after Pi release. Comparison with CBH-ParM, another ParM from Clostridum botulinum, showed that subunit-subunit interacting regions largely differ, preventing co-polymerization, implying a selection pressure in evolution to prevent interference between different ParMRC systems.

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Koh, A., Ali, S., Popp, D., Tanaka, K., Kitaoku, Y., Miyazaki, N., Kenji, I., Mitsuoka, K., Robinson, R. C., Narita, A.. 2022-03-07. An actin-like filament from Clostridium botulinum exhibits a novel mechanism of filament dynamics. https://doi.org/10.1101/2022.03.07.483215

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