Patent DE-102006057975-A1 (DE)
Title: Detection of microorganisms and/or their activity by biosensors, by immobilizing ligands for binding a receptor at a substrate surface or immobilizing the receptor for the ligands at the surface in chemical-, physical- or biological manner
Inventor: OSTERMANN KAI
IPC: C12Q1/02
Filed: 2006-12-01
Abstract: The detection of microorganisms and/or their activity using biosensors, comprises area-wise immobilization of signal molecule ligands for binding a receptor at a surface of a substrate (1) or immobilizing the receptor for the ligands at the surface of the substrate in chemical-, physical- or biological manner. By the bonding of ligands, which are sent from the microorganisms into a process quorum of sensing, the caused physical- or physico-chemical changes detected by sensor are measurable at the receptors. The receptors are provided with a sort of- or different sorts of fluorescence markers. The detection of microorganisms and/or their activity using biosensors, comprises area-wise immobilization of signal molecule ligands for binding of a receptor at a surface of a substrate (1) or immobilizing the receptor for the ligands at the surface of the substrate in chemical-, physical- or biological manner. By the bonding of ligands, which are sent from the microorganisms into a process quorum of sensing, the caused physical- or physico-chemical changes detected by sensor are measurable at the receptors. For the production of fusion proteins or peptides by recombination techniques, amino acid sequences of receptors are changed in such a way that a change of charge, mass, light, conformation or enzymatic reaction takes place in chemical- or physical manner. The ligands are bound at the surface, the receptors are bound at the ligands and the receptors of microorganisms are delivered in the process quorum of the sensing. The receptors are separated with ligands of the medium, and the separation instrumentation is detected by the changes of the charge, mass, optical- and magnetic characteristic, charge distribution or enzymatic activity. The biosensor is calibrated by accumulation of particles at the ligands or receptors. The surface of the substrate bound with the single molecules and with the receptors, is regenerated by a repeated coating with the receptor. The fusion of proteins or the peptide is changed in such a way that the mass of the fusion protein significantly increases. The peptide is arginine, histidine or lysine for a positive net charge or the peptides contain asparagine acid or glutamine acid for a negative net charge. The receptors in their amino acid sequences are changed in such a way that an affinity between the signal molecule and the receptor is increased or decreased. The receptors are provided with a sort of- or different sorts of fluorescence markers, which are fluorescence proteins or quantum dots. The signal molecule is an autoinducer-1 (AI-1) and/or an autoinducer-2 (AI-2) and/or its combinations. The receptor is either autoinducer 2-binding periplasmic protein LuxP-molecule or a genetically produced derivative. The peptides exhibit a self-fluorescence or cause enzymatic light reaction by the addition of the substrate molecules. By the recombination techniques, an additional protein, which exhibits proteolytic-, lipolytic- or nucleolytic function, is added at the receptors to produce fusion proteins. An independent claim is included for biosensors for the detection of microorganisms and/or their activity.