Design and application of a lactulose biosensor
نویسندگان
چکیده
In this study the repressor of Escherichia coli lac operon, LacI, has been engineered for altered effector specificity. A LacI saturation mutagenesis library was subjected to Fluorescence Activated Cell Sorting (FACS) dual screening. Mutant LacI-L5 was selected and it is specifically induced by lactulose but not by other disaccharides tested (lactose, epilactose, maltose, sucrose, cellobiose and melibiose). LacI-L5 has been successfully used to construct a whole-cell lactulose biosensor which was then applied in directed evolution of cellobiose 2-epimerase (C2E) for elevated lactulose production. The mutant C2E enzyme with ~32-fold enhanced expression level was selected, demonstrating the high efficiency of the lactulose biosensor. LacI-L5 can also be used as a novel regulatory tool. This work explores the potential of engineering LacI for customized molecular biosensors which can be applied in practice.
منابع مشابه
Design and application of a bioluminescent biosensor for detection of toxicity using Huh7-CMV-luc cell line
Cell-based biosensors (CBBs) are becoming important tools for biosecurity applications and rapid diagnostics in food microbiology for their unique capability of detecting hazardous materials. Pollutants, such as heavy metals and chemicals, are now considered as a global threat and are associated with detrimental health outcomes. Fast and accurate detection of pollutants is essential to reduce t...
متن کاملDesign and application of a bioluminescent biosensor for detection of toxicity using Huh7-CMV-luc cell line
Cell-based biosensors (CBBs) are becoming important tools for biosecurity applications and rapid diagnostics in food microbiology for their unique capability of detecting hazardous materials. Pollutants, such as heavy metals and chemicals, are now considered as a global threat and are associated with detrimental health outcomes. Fast and accurate detection of pollutants is essential to reduce t...
متن کاملPerformance Investigation of Pentacene Based Organic Double Gate Field Effect Transistor and its Application as an Ultrasensitive Biosensor
In this paper, the electrical performance of double gate organic field effecttransistor (DG-OFET) are thoroughly investigated and feasibility of the deviceas an efficient biosensor is comprehensively assessed. The introduced deviceprovides better gate control over the channel, yielding better charge injectionproperties from source to channel and providing higher on-state...
متن کاملRapid determination of lactulose in milk by microdialysis and biosensors.
A simple and rapid flow system for the determination of lactulose in milk samples was developed. It is based on the hydrolysis of lactulose to galactose and fructose by the enzyme beta-galactosidase immobilised in a reactor. The amount of fructose produced was measured with an electrochemical biosensor based on the fructose dehydrogenase enzyme, K3[Fe(CN)6] as mediator and a platinum based elec...
متن کاملThe obtain optimum production conditions for Glucose Oxidase biosensor using software Qualtek-4
The Glucose Oxidase (Gox) electrochemical sensors were used to detect a little amount of glucose. In this paper, the pure platinum plate (length of 5 cm and a width of 3 mm), the Ag/AgCl electrode and platinum electrode (diameter of 1 mm) were applied as a working electrode (W.E), reference electrode and auxiliary electrode sequential. Factors measured, glucose concentration and pH is Phosphate...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 7 شماره
صفحات -
تاریخ انتشار 2017