title: Biosensors based on membrane transport proteins.
abstract: We propose a novel class of biosensors based on membrane bound receptors or transport proteins as the sensing element. The protein is incorporated in a planar lipid bilayer which covers the transducer. The transducer may detect an electric current, a voltage, or a change in fluorescence. A prototype lactose sensor is presented which consists of a quartz slide covered by a lipid membrane containing the protein lactose permease from Escherichia coli. This protein is a lactose/H+ cotransporter, hence lactose in the external medium initiates lactose/H+ cotransport across the lipid membrane. This leads to a rise in proton concentration in the small volume between the lipid membrane and the quartz surface which can be detected by a pH-sensitive fluorescence dye.
authors.affiliation: Max-Planck-Institut für Biologie, Tübingen, FRG.
authors.forename: H
authors.initials: H
authors.lastname: Kiefer
authors.forename: B
authors.initials: B
authors.lastname: Klee
authors.forename: E
authors.initials: E
authors.lastname: John
authors.forename: Y D
authors.initials: YD
authors.lastname: Stierhof
authors.forename: F
authors.initials: F
authors.lastname: Jähnig
mesh_terms: D001190:Arylsulfonates; D015374:Biosensing Techniques; D001709:Biotechnology; D002352:Carrier Proteins; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes; D006863:Hydrogen-Ion Concentration; D007785:Lactose / Q000032:analysis; D008051:Lipid Bilayers; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009004:Monosaccharide Transport Proteins; D027981:Symporters
chemical_list: D001190:Arylsulfonates; D002352:Carrier Proteins; D029968:Escherichia coli Proteins; D005456:Fluorescent Dyes; C050221:LacY protein, E coli; D008051:Lipid Bilayers; D008565:Membrane Proteins; D026901:Membrane Transport Proteins; D009004:Monosaccharide Transport Proteins; D027981:Symporters; C021499:lactose permease; C005047:pyranine; D007785:Lactose