G01N2333/952

Means and methods for the determination of the biological activity of neurotoxin polypeptides in cells
11976110 · 2024-05-07 · ·

The present invention pertains to a method for directly determining the biological activity of a Neurotoxin polypeptide in cells, comprising the steps of: a) incubating cells susceptible to Neurotoxin intoxication with a Neurotoxin polypeptide for a time and under conditions which allow for the Neurotoxin polypeptide to exert its biological activity; b) fixing the cells and, optionally, permeabilizing the cells with a detergent; c) contacting the cells with at least a first capture antibody specifically binding to the non-cleaved and Neurotoxin-cleaved substrate and with at least a second capture antibody specifically binding to the cleavage site of the Neurotoxin-cleaved substrate, under conditions which allow for binding of said capture antibodies to said substrates; d) contacting the cells with at least a first detection antibody specifically binding to the first capture antibody, under conditions which allow for binding of said first detection antibody to said first capture antibody, thus forming first detection complexes, and at least a second detection antibody specifically binding to the second capture antibody, under conditions which allow for binding of said second detection antibody to said second capture antibody, thus forming second detection complexes; e) determining the amount of the first and second detection complexes of step d), and f) calculating the amount of substrate cleaved by said Neurotoxin polypeptide in said cells by means of the second detection complexes, thereby determining the biological activity of said Neurotoxin polypeptide in said cells. The invention further provides for a kit for carrying out the method of the invention.

METHODS OF GENERATING AND SCREENING FOR LYTIC CHIMERIC POLYPEPTIDES
20190249156 · 2019-08-15 · ·

The present invention relates to novel methods of generating and screening for chimeric polypeptides, which can be used in the treatment and prophylaxis of pathogenic bacterial contamination, colonisation and infection. The novel methods are based on random recombination of protein domains, and the chimeric polypeptides obtainable by the methods according to the invention are characterized in that they comprise at least one enzymatic active domain (EAD) and at least one cell binding domain (CBD). The present invention also relates to a library of chimeric polypeptides obtainable by the methods of the present invention.

Immuno-based retargeted endopeptidase activity assays

The present specification discloses a retargeted endopeptidase pharmaceutical wherein the activity has been determined by the methods disclosed.

Cell-free assay device and methods of use

Provided herein is a cell-free assay device, sometimes comprising a lipid bilayer and an endopeptidase assay component, for characterizing a pore forming protein. In some embodiments provided herein is an apparatus comprising a pressure system for characterizing an interaction. Also, provided herein are methods for using a cell-free assay device to characterize a pore forming protein and/or a test substance.

Assay with synaptobrevin based moiety

Compositions and methods for improved cell-based methods of characterizing botulinum neurotoxins are provided. Cells utilized in these methods include a reporting construct that is cleaved following uptake and processing of botulinum neurotoxin by the cell, resulting in proteolysis of the portion of the reporting construct that is released following cleavage. The released portion includes a fluorophore and amino acid substitutions or sequences that enhance the rate of proteolysis. A pair of reporting constructs can be utilized in which one member of the pair is modified to resist cleavage by the botulinum neurotoxin while co-localizing with the remaining member of the pair.

PROTEIN SEQUENCING METHOD AND REAGENTS

The invention describes methods and reagents useful for sequencing polypeptide molecules. The method comprises affixing a polypeptide to a substrate and contacting the polypeptide with a plurality of probes that selectively bind to a terminal amino acid or a terminal amino acid derivative. Probes bound to the polypeptide molecule are then identified before cleaving the terminal amino acid or terminal amino acid derivative of the polypeptide. Also provided are probe compositions comprising (a) a ClpS variant comprising at least 80% sequence identity to SEQ ID NO: 1, wherein the ClpS variant binds to an N-terminal amino acid or a N-terminal amino acid derivative with a different selectivity than a wild-type ClpS; and (b) a detectable label.

Methods of generating and screening for lytic chimeric polypeptides

The present invention relates to novel methods of generating and screening for chimeric polypeptides, which can be used in the treatment and prophylaxis of pathogenic bacterial contamination, colonization and infection. The novel methods are based on random recombination of protein domains, and the chimeric polypeptides obtainable by the methods according to the invention are characterized in that they comprise at least one enzymatic active domain (EAD) and at least one cell binding domain (CBD). The present invention also relates to a library of chimeric polypeptides obtainable by the methods of the present invention.

Translocation of a polymer through a nanopore

Embodiments of the present disclosure are directed to methods, systems and devices, for analyzing the molecules. For example, in some embodiments, a system is provided which includes a first volume of conducting fluid, a second volume of conducting fluid, an orifice in communication with the first and second volumes of fluid, and means for applying an electric potential difference between the first and second volumes of fluid. In some such embodiments, a conjugate product is provided which includes charged polymers each having attached thereto at least one first molecule for analysis, where the product carries a predetermined charge greater than the charge on the first molecule, and upon dissolving the product in the first volume of fluid, the product is directed into the orifice.

METHOD FOR DETECTING STAPHYLOCOCCUS CONTAINED IN MILK
20190079089 · 2019-03-14 · ·

The object is to provide a lysis method, lysis treatment solution, detection method using an immunochromatographic device, and detection kit comprising an immunochromatographic device for detecting whether causative bacterium of mastitis is a staphylococcus or not by using milk of a livestock animal. There is provided a method for lysing a staphylococcus, which comprises the step of mixing a lysis agent containing a lytic enzyme, and at least one kind of ampholytic surfactant, and preferably further containing at least one kind of nonionic surfactant, with milk obtained form a livestock animal to lyse a staphylococcus existing in the milk. The lytic enzyme is preferably lysostaphin.

METHOD FOR DETECTING STAPHYLOCOCCUS CONTAINED IN MILK
20190049446 · 2019-02-14 · ·

The object is to provide a lysis method, lysis treatment solution, detection method using an immunochromatographic device, and detection kit comprising an immunochromatographic device for detecting whether causative bacterium of mastitis is a staphylococcus or not by using milk of a livestock animal. There is provided a method for lysing a staphylococcus, which comprises the step of mixing a lysis agent containing a lytic enzyme, and at least one kind of ampholytic surfactant, and preferably further containing at least one kind of nonionic surfactant, with milk obtained form a livestock animal to lyse a staphylococcus existing in the milk. The lytic enzyme is preferably lysostaphin.