TY - JOUR
T1 - Engineering ligand-specific biosensors for aromatic amino acids and neurochemicals
AU - Rottinghaus, Austin G.
AU - Xi, Chenggang
AU - Amrofell, Matthew B.
AU - Yi, Hyojeong
AU - Moon, Tae Seok
N1 - Publisher Copyright:
© 2021 Elsevier Inc.
PY - 2022/3/16
Y1 - 2022/3/16
N2 - Microbial biosensors have diverse applications in metabolic engineering and medicine. Specific and accurate quantification of chemical concentrations allows for adaptive regulation of enzymatic pathways and temporally precise expression of diagnostic reporters. Although biosensors should differentiate structurally similar ligands with distinct biological functions, such specific sensors are rarely found in nature and challenging to create. Using E. coli Nissle 1917, a generally regarded as safe microbe, we characterized two biosensor systems that promiscuously recognize aromatic amino acids or neurochemicals. To improve the sensors’ selectivity and sensitivity, we applied rational protein engineering by identifying and mutagenizing amino acid residues and successfully demonstrated the ligand-specific biosensors for phenylalanine, tyrosine, phenylethylamine, and tyramine. Additionally, our approach revealed insights into the uncharacterized structure of the FeaR regulator, including critical residues in ligand binding. These results lay the groundwork for developing kinetically adaptive microbes for diverse applications. A record of this paper's transparent peer review process is included in the supplemental information.
AB - Microbial biosensors have diverse applications in metabolic engineering and medicine. Specific and accurate quantification of chemical concentrations allows for adaptive regulation of enzymatic pathways and temporally precise expression of diagnostic reporters. Although biosensors should differentiate structurally similar ligands with distinct biological functions, such specific sensors are rarely found in nature and challenging to create. Using E. coli Nissle 1917, a generally regarded as safe microbe, we characterized two biosensor systems that promiscuously recognize aromatic amino acids or neurochemicals. To improve the sensors’ selectivity and sensitivity, we applied rational protein engineering by identifying and mutagenizing amino acid residues and successfully demonstrated the ligand-specific biosensors for phenylalanine, tyrosine, phenylethylamine, and tyramine. Additionally, our approach revealed insights into the uncharacterized structure of the FeaR regulator, including critical residues in ligand binding. These results lay the groundwork for developing kinetically adaptive microbes for diverse applications. A record of this paper's transparent peer review process is included in the supplemental information.
KW - aromatic amino acid
KW - aromatic neurochemical
KW - directed evolution
KW - probiotic
KW - protein engineering
KW - specific sensors
UR - http://www.scopus.com/inward/record.url?scp=85124352339&partnerID=8YFLogxK
U2 - 10.1016/j.cels.2021.10.006
DO - 10.1016/j.cels.2021.10.006
M3 - Article
C2 - 34767760
AN - SCOPUS:85124352339
SN - 2405-4712
VL - 13
SP - 204-214.e4
JO - Cell Systems
JF - Cell Systems
IS - 3
ER -