349614 Production of Acyl Homoserine Lactones in Bacillus Megaterium

Monday, November 4, 2013
Grand Ballroom B (Hilton)
Lakshmi Nathan1,2, Manuel R. Jiménez Díaz2 and Cynthia H. Collins2, (1)Chemical Engineering, Texas A&M University, College Station, TX, (2)Chemical and Biological Engineering, Rensselaer Polytechnic Institute, Troy, NY

In nature, communities consisting of multiple microbial species can cooperate to perform complex biochemical processes. However, traditional biotechnology has focused on optimizing a single organism for a particular application. Synthetically engineered communities similar to these microbial consortia found in nature could use a division of labor approach to overcome some of the challenges of using a single organism, such as high metabolic loads or buildup of toxic byproducts.  Synthetically developed communication could assist in manipulation and control of engineered consortia. Acyl-homoserine lactones (AHLs) are used by some bacteria for quorum sensing, in which they coordinate gene expression based on density. We hypothesize that with some modifications, AHLs can be used for interspecies signaling. Specifically, this work aims to use two AHLs, C4HSL and 3OC12HSL, to enable Bacillus megaterium to send signals to Escherichia coli. Each of these species is widely used in biotechnology, making them good candidates for use in synthetic consortia in industry. Genetic recombination was used to introduce genes encoding AHL synthases to B. megaterium and AHL response elements in E. coli. The E. coli reporter was incubated with supernatant collected form B. megaterium and the resulting fluorescence was compared to a standard curve to determine the AHL concentration in the supernatant. E. coli responded to C4HSL concentrations above 2 μM, while production levels in B. megaterium were between 40 and 400 nM. The 3OC12HSL reporter was sensitive to concentrations above 10 nM. However, production of 3OC12HSL was not detected. If production or reporter sensitivity is increased, C4HSL has the potential to be used in an interspecies signaling pathway. Further study is needed to determine if 3OC12HSL can be produced at detectable concentrations.

Extended Abstract: File Not Uploaded