Various embodiments of a light detection device and a method of using the device are disclosed. In one or more embodiments, the light detection device can include a housing that extends along a housing axis between top and bottom surfaces. The device can also include a port that is adapted to receive a sample, and a door connected to the housing. The door can include an actuator portion adapted to selectively move the door between a closed position and an open position, and a cover portion connected to the actuator portion and adapted to close the port when the door is in the closed position and open the port when the door is in the open position to allow external access to the port.

The present invention relates to a method for detecting or quantifying ATP in a sample by using a blood glucose meter, the method including adding a sample to be detected to an ATP detection composition containing glucose and an enzyme involved in ATP regeneration so as to convert glucose into glucose-6-phosphate, and then measuring the glucose concentration by using a glucose meter, thereby detecting or quantifying ATP.

The present invention provides a measuring method for at least one of a kinase forward reaction substrate, a phosphorylated product thereof, and a precursor thereof, and includes a step of conducting an enzymatic cycling reaction by bringing at least a kinase, a first nucleotide coenzyme of the kinase, and a second nucleotide coenzyme having a different nucleoside moiety from the first nucleotide coenzyme into contact with a sample; a step of detecting a signal corresponding to a change of at least one of the first nucleotide coenzyme and a conversion product thereof, and the second nucleotide coenzyme and a conversion product thereof; and (3) a step of calculating, on the basis of the detected change of the signal, an amount of the kinase forward reaction substrate and/or the phosphorylated product thereof contained in the sample.

The invention relates to the detection of the cofactor reduced nicotinamide adenine dinucleotide phosphate (NADPH). Provided is a sensor molecule for the resonance energy transfer (RET)-based detection of NADPH, the sensor comprising a segment A connected via a linker to a segment B, wherein each of segment A and segment B comprises a member of a RET pair comprising a donor moiety and an acceptor moiety, further characterized in that (i) segment A comprises a binding protein (BP) for NADPH, the BP being dihydrofolate reductase (DHFR; EC 1.5.1.3) or a functional homolog, fragment, derivative or variant thereof, showing the desired NADPH binding properties, and wherein the BP comprises a heterologous protein domain inserted at or replacing at least part of the region corresponding to positions (20) to (27) of E. coli DHFR, said heterologous protein domain comprising the member of the RET pair; (ii) segment B comprises a ligand (L) capable of intramolecular binding to said BP only in the presence of NADPH; such that the donor moiety and the acceptor moiety are in a suitable juxtaposition to yield a RET signal when L is bound to BP, and wherein NADPH-induced binding of L to BP results in an increase in RET efficiency.

Provided herein are inhibitor-resistant luciferase mutants, and methods of use thereof. In particular, luciferase mutants are provided that are thermal stable and exhibit improved stability in the presence of luciferin break-down products, such as dehydroluciferin. Further provided are assay systems comprising inhibitor-resistant luciferase mutants and amino acid sequences of the inhibitor-resistant luciferase mutants.

Various embodiments of a light detection device and a system that utilizes such device are disclosed. In one or more embodiments, the light detection device can include a housing that includes a port disposed in a top surface, a receptacle disposed within the housing and adapted to receive a sample, a detector disposed within the housing along an optical axis and including an input surface having an active area, and a reflector disposed within the housing along the optical axis between the receptacle and the input surface of the detector. The reflector can include an input aperture disposed adjacent the receptacle, an output aperture disposed adjacent the input surface of the detector, and a reflective surface that extends between the input aperture and the output aperture.

A kit for detecting bacterial ATP in a sample is provided. The kit comprises an aqueous composition having a pH of about 6.0 to 7.2. The aqueous composition comprises effective amounts of a polyol, a buffer reagent, a protein, and ATP-diphosphohydrolase. A method of using the kit to detect bacterial ATP is also provided.

A method for detecting lactic acid and/or acetic acid bacteria in a food-processing matrix is taught, using microbial flora including a lactic acid and/or acetic acid bacterial flora and a fungal flora. The bacterial flora contains an adenosine triphosphate of bacterial origin, and the fungal flora contains an adenosine triphosphate of fungal origin. The method comprises applying, to the matrix, before a first time limit, an antifungal having an antifungal action which is lethal, on the fungal flora, and at a second time limit, an antibiotic action which is non lethal, at a second time limit after the first time limit, on the bacterial flora. The microbial flora is detected between the first time limit and the second time limit; the lethal antifungal action releases, into the matrix, for the first time limit, adenosine triphosphate of fungal origin and in which the microbial flora is detected between the first time limit and the second time limit.

An apyrase enzyme, characterized by that the apyrase comprises a polypeptide sequence having at least 70% sequence identity to the wild-type Shigella flexneri apyrase of SEQ ID NO:1, wherein said sequence differs from SEQ ID NO:1 at least in that the sequence comprises at least one amino-acid substitution of a residue aligning with a residue selected from: F53, L66 and E77; and the apyrase catalyzes the dephosphorylation of at least one organic phosphate with at least 10-fold lower K.sub.m compared to the apyrase of SEQ ID NO:1. Uses of said apyrase in ATP elimination and dephosphorylation of organic phosphates.

An apparatus and kit for the detection of ATP in a liquid sample is provided. The apparatus and kit comprise a liquid reagent composition comprising luciferin and a sampling device having a sampling portion and a handling portion. The sampling portion is adapted to acquire and releasably retain a predetermined volume of a liquid sample in one or more cavity that is not substantially defined by space between a plurality of fibers. The sampling device comprises a dry coating that includes an effective amount of a pH-adjusting reagent that, when contacted with a liquid reagent composition having a pH of about 6.8 or lower, changes the pH of the liquid reagent composition to 6.9 or higher. A method of use of the apparatus or kit is also provided.