TY - JOUR
T1 - A Whole-Cell Surface Plasmon Resonance Sensor Based on a Leucine Auxotroph of Escherichia coli Displaying a Gold-Binding Protein
T2 - Usefulness for Diagnosis of Maple Syrup Urine Disease
AU - Woo, Min Ah
AU - Park, Jung Hun
AU - Cho, Daeyeon
AU - Sim, Sang Jun
AU - Kim, Moon Il
AU - Park, Hyun Gyu
N1 - Funding Information:
This work was financially supported by the Center for BioNano Health-Guard funded by the Ministry of Science, ICT, and Future Planning (MSIP) of Korea as a Global Frontier Project (Grant H-GUARD-2013M3A6B2078964) and by the Basic Science Research Program through the NRF funded by the Ministry of Education [no. 2015R1A2A1A01005393]. This study was also supported by the National Research Foundation of Korea (NRF) grants [no. NRF-2013R1A2A1A01015644] of the MSIP of Korea. This research was also supported by the Korea Food Research Institute.
Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/3/1
Y1 - 2016/3/1
N2 - We developed a whole-cell surface plasmon resonance (SPR) sensor based on a leucine auxotroph of Escherichia coli displaying a gold-binding protein (GBP) in response to cell growth and applied this sensor to the diagnosis of maple syrup urine disease, which is represented by the elevated leucine level in blood. The leucine auxotroph was genetically engineered to grow displaying GBP in a proportion to the concentration of target amino acid leucine. The GBP expressed on the surface of the auxotrophs directly bound to the golden surface of an SPR chip without the need for any additional treatment or reagents, which consequently produced SPR signals used to determine leucine levels in a test sample. Gold nanoparticles (GNPs) were further applied to the SPR system, which significantly enhanced the signal intensity up to 10-fold by specifically binding to GBP expressed on the cell surface. Finally, the diagnostic utility of our system was demonstrated by its employment in reliably determining different statuses of maple syrup urine disease based on a known cutoff level of leucine. This new approach based on an amino acid-auxotrophic E. coli strain expressing a GBP that binds to an SPR sensor holds great promise for detection of other metabolic diseases of newborn babies including homocystinuria and phenylketonuria, which are also associated with abnormal levels of amino acids.
AB - We developed a whole-cell surface plasmon resonance (SPR) sensor based on a leucine auxotroph of Escherichia coli displaying a gold-binding protein (GBP) in response to cell growth and applied this sensor to the diagnosis of maple syrup urine disease, which is represented by the elevated leucine level in blood. The leucine auxotroph was genetically engineered to grow displaying GBP in a proportion to the concentration of target amino acid leucine. The GBP expressed on the surface of the auxotrophs directly bound to the golden surface of an SPR chip without the need for any additional treatment or reagents, which consequently produced SPR signals used to determine leucine levels in a test sample. Gold nanoparticles (GNPs) were further applied to the SPR system, which significantly enhanced the signal intensity up to 10-fold by specifically binding to GBP expressed on the cell surface. Finally, the diagnostic utility of our system was demonstrated by its employment in reliably determining different statuses of maple syrup urine disease based on a known cutoff level of leucine. This new approach based on an amino acid-auxotrophic E. coli strain expressing a GBP that binds to an SPR sensor holds great promise for detection of other metabolic diseases of newborn babies including homocystinuria and phenylketonuria, which are also associated with abnormal levels of amino acids.
UR - http://www.scopus.com/inward/record.url?scp=84959517049&partnerID=8YFLogxK
U2 - 10.1021/acs.analchem.5b04648
DO - 10.1021/acs.analchem.5b04648
M3 - Article
C2 - 26828904
AN - SCOPUS:84959517049
VL - 88
SP - 2871
EP - 2876
JO - Analytical Chemistry
JF - Analytical Chemistry
SN - 0003-2700
IS - 5
ER -