Reconstitution of the quorum sensing pathway reveals a direct role for the integral membrane protease MroQ in pheromone biosynthesis.

TitleReconstitution of the quorum sensing pathway reveals a direct role for the integral membrane protease MroQ in pheromone biosynthesis.
Publication TypeJournal Article
Year of Publication2022
AuthorsZhao, A, Bodine, SP, Xie, Q, Wang, B, Ram, G, Novick, RP, Muir, TW
JournalProc Natl Acad Sci U S A
Volume119
Issue33
Paginatione2202661119
Date Published2022 Aug 16
ISSN1091-6490
KeywordsBacterial Proteins, Membrane Proteins, Peptide Hydrolases, Pheromones, Quorum Sensing, Staphylococcus aureus, Trans-Activators, Virulence
Abstract

<p>In virulence is under the control of a quorum sensing (QS) circuit encoded in the accessory gene regulator () genomic locus. Key to this pathogenic behavior is the production and signaling activity of a secreted pheromone, the autoinducing peptide (AIP), generated following the ribosomal synthesis and posttranslational modification of a precursor polypeptide, AgrD, through two discrete cleavage steps. The integral membrane protease AgrB is known to catalyze the first processing event, generating the AIP biosynthetic intermediate, AgrD (1-32) thiolactone. However, the identity of the second protease in this biosynthetic pathway, which removes an N-terminal leader sequence, has remained ambiguous. Here, we show that membrane protease regulator of QS (MroQ), an integral membrane protease recently implicated in the response, is directly involved in AIP production. Genetic complementation and biochemical experiments reveal that MroQ proteolytic activity is required for AIP biosynthesis in specificity group I and group II, but not group III. Notably, as part of this effort, the biosynthesis and AIP-sensing arms of the QS circuit were reconstituted together in vitro. Our experiments also reveal the molecular features guiding MroQ cleavage activity, a critical factor in defining specificity group identity. Collectively, our study adds to the molecular understanding of the response and virulence.</p>

DOI10.1073/pnas.2202661119
Alternate JournalProc Natl Acad Sci U S A
PubMed ID35939668
PubMed Central IDPMC9388083
Grant ListAI042783 / / HHS | National Institutes of Health (NIH) /