Regulation by the quorum sensor from Vibrio indicates a receptor function for the membrane anchors of adenylate cyclases
Abstract
Adenylate cyclases convert intra- and extracellular stimuli into a second messenger cAMP signal. Many bacterial and most eukaryotic ACs possess membrane anchors with six transmembrane spans. We replaced the anchor of the AC Rv1625c by the quorum-sensing receptor from Vibrio harveyi which has an identical 6TM design and obtained an active, membrane-anchored AC. We show that a canonical class III AC is ligand-regulated in vitro and in vivo. At 10 µM, the cholera-autoinducer CAI-1 stimulates activity 4.8-fold. A sequence based clustering of membrane domains of class III ACs and quorum-sensing receptors established six groups of potential structural and functional similarities. The data support the notion that 6TM AC membrane domains may operate as receptors which directly regulate AC activity as opposed and in addition to the indirect regulation by GPCRs in eukaryotic congeners. This adds a completely novel dimension of potential AC regulation in bacteria and vertebrates.
Article and author information
Author details
Reviewing Editor
- Michael A Marletta, University of California, Berkeley, United States
Version history
- Received: November 17, 2015
- Accepted: February 26, 2016
- Accepted Manuscript published: February 27, 2016 (version 1)
- Version of Record published: March 29, 2016 (version 2)
- Version of Record updated: February 8, 2017 (version 3)
Copyright
© 2016, Beltz et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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