Abstract: The invention provides compositions containing a mixture of (a) an enzyme that possesses substantial 3?-5? exonuclease activity (b) a DNA polymerase with less 3?-5? exonuclease activity than the enzyme with substantial 3?-5? exonuclease activity. Preferably, the DNA polymerase for inclusion in the compositions are DNA polymerases that substantially lack 3?-5? exonuclease activity. A preferred embodiment of the invention is a composition comprising Taq DNA polymerase (isolated from Thermus aquaticus) and Pfu DNA polymerase (isolated from Pvrococcus furiosus). Another aspect of the invention is to provide methods for synthesizing polynucleotides using compositions comprising an enzyme that possesses substantial 3?-5? exonuclease activity and a DNA polymerase with less 3?-5? exonuclease activity than the enzymes possessing substantial 3?-5? exonuclease activity, preferably a DNA polymerase that substantially lacks 3?-5? exonuclease activity.

Abstract: The invention encompasses methods for enriching for and identifying a polymorphism within a nucleic acid sample either by separating a subset of a nucleic acid sample or by selectively replicating a subset of a nucleic acid sample such that the polymorphism is contained within a nucleic acid population with reduced complexity, and then identifying the polymorphism within the enriched nucleic acid sample.

Abstract: The invention encompasses methods for enriching for and identifying a polymorphism within a nucleic acid sample either by separating a subset of a nucleic acid sample or by selectively replicating a subset of a nucleic acid sample such that the polymorphism is contained within a nucleic acid population with reduced complexity, and then identifying the polymorphism within the enriched nucleic acid sample.

Abstract: The invention encompasses methods for enriching for and identifying a polymorphism within a nucleic acid sample either by separating a subset of a nucleic acid sample or by selectively replicating a subset of a nucleic acid sample such that the polymorphism is contained within a nucleic acid population with reduced complexity, and then identifying the polymorphism within the enriched nucleic acid sample.

Abstract: The invention provides a method of generating a signal indicative of the presence of a target nucleic acid sequence in a sample by forming a cleavage structure by incubating a sample comprising a target nucleic acid sequence with a probe, nucleic acid polymerase, nuclease and optionally a primer. The target nucleic acid is extended and circularized and a cleavage structure is formed. The cleavage structure is cleaved with a nuclease to generate a nucleic acid fragment which is indicative of the presence of a target nucleic acid sequence in the sample.

Abstract: The present invention is directed to kits and compositions for generating a signal indicative of the presence of a target nucleic acid sequence in a sample, comprising a nucleic acid polymerase lacking 5? to 3? exonuclease activity and a thermostable FEN nuclease consisting of a 5? to 3? exonuclease and/or endonuclease activity.

Abstract: The invention relates to nucleic acid compositions for use in sequential amplification detection assays which permit the detection of a nucleic acid target in a sample.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The present invention relates to a method for isolating from the immunological gene repertoire a gene coding for a receptor having the ability to bind a preselected ligand. Receptors produced by the gene isolated by the method, particularly catalytic receptors, are also contemplated.

Abstract: The invention relates to compositions for generating a signal indicative of the presence of a target nucleic acid in a sample, where the compositions include a probe having a 5? region and a 3? flap and a P. furiosus polymerase having 3? exonuclease activity.

Abstract: The invention provides compositions, kits and methods of generating a signal indicative of the presence of a target nucleic acid sequence in a sample by forming a cleavage structure. The cleavage structure is formed by incubating a sample containing a target nucleic acid with a downstream probe that forms a 3? flap when hybridized to the target. The cleavage structure is cleaved with a 3? nuclease and a detectable signal is produced.

Abstract: Provided herein are methods, compositions and kits for detecting a target nucleic acid. A target nucleic acid can be produced, for example, by a cleavage reaction in an assay for detection of biological samples. In one aspect, a described method comprises the following steps: hybridizing the target nucleic acid having a 5? end and a 3? end to a probe to form a circular hybridization complex; forming a covalent circular target nucleic acid using the probe as a template for nucleic acid synthesis; and detecting the covalent circular target nucleic acid.

Abstract: The invention relates to compositions and methods of generating a signal indicative of the presence of a target nucleic acid in a sample, where the method includes forming a cleavage structure by incubating a sample comprising a target nucleic acid with a probe. The invention also includes the steps of cleaving the cleavage structure with a nuclease to release a nucleic acid fragment to generate a signal, wherein generation of the signal is indicative of the presence of a target nucleic acid in a sample.

Abstract: The invention relates to compositions for generating a signal indicative of the presence of a target nucleic acid in a sample, where the compositions include an RNA polymerase, a FEN nuclease, and a probe.

Abstract: The invention relates to compositions for generating a signal indicative of the presence of a target nucleic acid in a sample. The compositions include a reverse transcriptase, a nuclease, an upstream primer and downstream probe.

Abstract: The invention provides methods of covalently joining nucleic acid molecules and methods of molecular cloning. The methods provide either sequential or simultaneous ligation of flanking or vector nucleic acid molecules to nucleic acid insert molecules by topoisomerase and DNA ligase. The methods provide for directional and non-directional covalent joining and cloning of nucleic acid molecules.