Ilamycins are dual inhibitors of ClpX and ClpC1 involved in proteostasis in Mycobacteria

Gao, Y.; Fang, C.; Zhou, B.; Hameed, H. M. A.; Sun, C.; Tian, X.; He, J.; Han, X.; Zhang, H.; Ju, J.; Chen, X.; Zhong, N.; Ma, J.; Xiong, X.; Zhang, T.

doi:10.1101/2024.02.24.581832

bioRxiv · 10.1101/2024.02.24.581832

Ilamycins are dual inhibitors of ClpX and ClpC1 involved in proteostasis in Mycobacteria

Gao, Y.·Fang, C.·Zhou, B.·Hameed, H. M. A.·Sun, C.·Tian, X.·He, J.·Han, X.·Zhang, H.·Ju, J.·Chen, X.·Zhong, N.·Ma, J.·Xiong, X.·Zhang, T.

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Abstract

The mycobacterial caseinolytic protease (Clp) system has been recognized as a promising therapeutic target. In this study, we identified two novel ilamycin analogs, ilamycin E (ILE) and ilamycin F (ILF), both targeting the ClpC1 component of the ClpC1P1P2 proteasome. ILE potently disrupts ClpC1P1P2-mediated proteolysis, leading to delayed bactericidal activity, while ILF also binds ClpC1, albeit with lower affinity. Notably, we discovered a unique mutation in clpX and a novel insertion in clpC1, both conferring resistance to ILE and ILF in mycobacterium, validated by gene editing. Furthermore, ILE can also inhibit the proteolytic activity of ClpXP1P2 in a manner dependent on the substrates tag sequence and adaptor. This first demonstration of clpX- and clpC1-mediated ilamycin resistance underscores the potential of ilamycins to target multiple components of the Clp protease system, offering a novel dual-target strategy for combating mycobacterial infections.

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Gao, Y., Fang, C., Zhou, B., Hameed, H. M. A., Sun, C., Tian, X., He, J., Han, X., Zhang, H., Ju, J., Chen, X., Zhong, N., Ma, J., Xiong, X., Zhang, T.. 2024-02-25. Ilamycins are dual inhibitors of ClpX and ClpC1 involved in proteostasis in Mycobacteria. https://doi.org/10.1101/2024.02.24.581832

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