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The marine diterpenes pseudopteroxazole (Ptx) and pseudopterosin G (PsG) target the integrity of the gram-positive cell wall

ABSTRACT: Pseudopteroxazole (Ptx) and the pseudopterosins are marine natural products with promising antibacterial potential. While Ptx has attracted interest for its anti-mycobacterial activity, pseudopterosins are active against several clinically relevant pathogens. Both compound classes exhibit low cytotoxicity and accessibility to targeted synthesis, yet their antibacterial mechanisms remain elusive. In this study, we investigated the modes of action of Ptx and pseudopterosin G (PsG) in Bacillus subtilis employing an unbiased approach that combines gel-based proteomics with a mathematical similarity analysis of response profiles. Proteomic responses to sublethal concentrations of Ptx and PsG were compared to a library of antibiotic stress response profiles revealing that both induce a stress response characteristic for agents targeting the bacterial cell envelope by interfering with membrane-bound steps of cell wall biosynthesis. Microscopy-based assays confirmed that both compounds compromise the integrity of the bacterial cell wall without disrupting the membrane potential.

INSTRUMENT(S): Synapt MS

ORGANISM(S): Bacillus Subtilis Subsp. Subtilis Str. 168

SUBMITTER: Niklas Janzing

LAB HEAD: Julia Bandow

PROVIDER: PXD045994 | Pride | 2024-01-04

REPOSITORIES: Pride

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			Action	DRS
	PsG_RAW.7z	Other
	PsG_SEARCH.zip	Other
	Ptx_RAW.zip	Other
	Ptx_SEARCH.zip	Other
	SpotList.xlsx	Xlsx

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