摘要:
A method for determining the presence of a predetermined target nucleotide sequence in the nucleic acid of a biological sample which comprises the steps:
(a) contacting, in solution, the sample and (i) a labeled first probe polynucleotide being capable of base pair binding to the target nucleotide sequence and (ii) an immobilizable or immobilized second probe polynucleotide which is capable of base pair binding selectively to the first probe polynucleotide in a region of first probe polynucleotide capable of base pair binding to the target nucleotide sequence, under conditions in which first probe polynucleotide can bind to target nucleotide sequence and can bind to second probe polynucleotide, (b) immobilizing the second probe polynucleotide, if immobilizable, with any labeled first probe polynucleotide bound thereto, and (c) detecting the labeled polynucleotide which is not immobilized with the immobilized or immobilizable second probe polynucleotide as a measure of the amount of target nucleotide sequence in the sample.
Also, a kit comprising such a labeled first polynucleotide and immobilizable second polynucleotide and immobilization means for immobilizing the immobilizable second polynucleotide together with any labeled first polynucleotide bound thereto. Also, a similar method or kit wherein the first probe polynucleotide is immobilizable or immobilized and the second probe polynucleotide is labeled.
摘要:
A diagnostic reagent is disclosed containing a complex of a probe polynucleotide (P) bound via purine/pyrimidine hydrogen bonding to a labeled polynucleotide (L). The probe (P) contains a target binding region (TBR) capable of binding to a target nucleotide sequence (G) of a biological sample. A method is disclosed in which contact with a sample containing the target nucleotide sequence (G) in the presence of a recombination protein and its cofactors causes binding, initially between G and a single-stranded portion (IBR) of the target binding region (TBR). Thereafter the labeled polynucleotide (L) is displaced from the complex by branch migration of (G) into the (P)/(L) binding region. Determination of displaced labeled polynucleotide (L) gives a value which is a function of the presence and concentration of target nucleotide sequence (G) in the sample. The presence of the recombination protein (such as the rec A protein from the enteric bacterium E. coli) enhances the rate of appearance of displaced labeled polynucleotide, especially when the reaction is conducted at or near physiological temperatures
摘要:
A diagnostic reagent is disclosed containing a complex of a probe polynucleotide (P) bound via purine/pyrimidine hydrogen bonding to a labeled polynucleotide (L). The probe (P) contains a target binding region (TBR) capable of binding to a target nucleotide sequence (G) of a biological sample. A method is disclosed in which contact with a sample containing the target nucleotide sequence (G) causes binding, initially between G and a single-stranded portion (IBR) of the target binding region (TBR). Thereafter the labeled polynucleotide (L) is displaced from the complex by branch migration of (G) into the (P)/(L) binding region. Determination of displaced labeled polynucleotide (L) gives a value which is a function of the presence and concentration of target nucleotide sequence (G) in the sample.