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Title: Engineering Escherichia coli for enhanced sensitivity to the autoinducer‐2 quorum sensing signal
Abstract The autoinducer‐2 (AI‐2) quorum sensing system is involved in a range of population‐based bacterial behaviors and has been engineered for cell–cell communication in synthetic biology systems. Investigation into the cellular mechanisms of AI‐2 processing has determined that overexpression of uptake genes increases AI‐2 uptake rate, and genomic deletions of degradation genes lowers the AI‐2 level required for activation of reporter genes. Here, we combine these two strategies to engineer anEscherichia colistrain with enhanced ability to detect and respond to AI‐2. In anE. colistrain that does not produce AI‐2, we monitored AI‐2 uptake and reporter protein expression in a strain that overproduced the AI‐2 uptake or phosphorylation units LsrACDB or LsrK, a strain with the deletion of AI‐2 degradation units LsrF and LsrG, and an “enhanced” strain with both overproduction of AI‐2 uptake and deletion of AI‐2 degradation elements. By adding up to 40 μM AI‐2 to growing cell cultures, we determine that this “enhanced” AI‐2 sensitive strain both uptakes AI‐2 more rapidly and responds with increased reporter protein expression than the others. This work expands the toolbox for manipulating AI‐2 quorum sensing processes both in native environments and for synthetic biology applications.  more » « less
Award ID(s):
1807604 1435957 1805274
PAR ID:
10459229
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Biotechnology Progress
Volume:
35
Issue:
6
ISSN:
8756-7938
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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