Enhanced electrochemical measurement of β-galactosidase activity in whole cells by coexpression of lactose permease, LacY
Abstract
Whole-cell biosensing links the sensing and computing capabilities of microbes to the generation of a detectable reporter. Whole cells enable dynamic biological computation (filtered noise, amplified signals, logic gating etc.). Enzymatic reporters enable in situ signal amplification. Electrochemical measurements are easily quantified and work in turbid environments. In this work we show how the coexpression of the lactose permease, LacY, dramatically improves electrochemical sensing of β-galactosidase (LacZ) expressed as a reporter in whole cells. The permease facilitates transport of the LacZ substrate, 4-aminophenyl β-d-galactopyranoside, which is converted to redox active p-aminophenol, which, in turn, is detected via cyclic voltammetry or chronocoulometry. We show a greater than fourfold improvement enabled by lacY coexpression in cells engineered to respond to bacterial signal molecules, pyocyanin and quorum-sensing autoinducer-2.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Nov 01, 2022
- Source ID
- 10.2144/btn-2022-0090
Entities
People
- Chen-yu Chen
- Eric Vanarsdale
- Gregory F Payne
- Juliana Pitzer
- Kristina Stephens
- Sally Wang
- William E. Bentley
Organizations
- Defense Threat Reduction Agency
- Division of Chemical, Bioengineering, Environmental, and Transport Systems
- Division of Molecular & Cellular Biosciences
- Office of Biological and Environmental Research
- University of Maryland