The disclosure provides a high-fidelity polymerase with preference for gapped DNA and use thereof. The Klenow fragment (KlenDr) derived from Deinococcus radiodurans DNA polymerase I, which has the high-fidelity polymerization characteristics, is independent of 3′-5′ proofreading exonuclease activity, has the preference for binding gapped DNA, and is different from the existing commercial high-fidelity polymerase. Due to the specific affinity of KlenDr to gapped DNA substrate, the 3′ end of the forward primer will not be cut off, and the downstream nucleotide chain is rarely replaced.

There is provided a method of detecting the presence of a nucleic acid target sequence in which two oligonucleotides are used to forma three-way junction with the target sequence to allow detection of the target sequence. Alternatively, three oligonucleotides can be used to form a four-way junction with the target sequence to allow detection of the target sequence.

There is provided a method of detecting the presence of a nucleic acid target sequence in which two oligonucleotides are used to forma three-way junction with the target sequence to allow detection of the target sequence. Alternatively, three oligonucleotides can be used to form a four-way junction with the target sequence to allow detection of the target sequence.

Presented herein are altered polymerase enzymes for improved incorporation of nucleotides and nucleotide analogues, in particular altered polymerases that maintain high fidelity under reduced incorporation times, as well as methods and kits using the same.

Presented herein are altered polymerase enzymes for improved incorporation of nucleotides and nucleotide analogues, in particular altered polymerases that maintain high fidelity under reduced incorporation times, as well as methods and kits using the same.

In some embodiments, the present teachings provide compositions, systems, methods and kits for generating a population of nucleic acid fragments. In some embodiments, nucleic acids can be fragmented enzymatically. For example, methods for generating a population of nucleic acid fragments can include a nucleic acid nicking reaction. In one embodiment, the methods can include a nick translation reaction. A nicking reaction can introduce nicks at random positions on either strand of a double-stranded nucleic acid. A nick translation reaction can move the position of nicks to a new position so that the new positions of two of the nicks are aligned to create a double-stranded break. In some embodiments, methods for generating a population of nucleic acid fragments can include joining at least one end of a fragmented nucleic acid to one or more oligonucleotide adaptors.

In some embodiments, the present teachings provide compositions, systems, methods and kits for generating a population of nucleic acid fragments. In some embodiments, nucleic acids can be fragmented enzymatically. For example, methods for generating a population of nucleic acid fragments can include a nucleic acid nicking reaction. In one embodiment, the methods can include a nick translation reaction. A nicking reaction can introduce nicks at random positions on either strand of a double-stranded nucleic acid. A nick translation reaction can move the position of nicks to a new position so that the new positions of two of the nicks are aligned to create a double-stranded break. In some embodiments, methods for generating a population of nucleic acid fragments can include joining at least one end of a fragmented nucleic acid to one or more oligonucleotide adaptors.

Methods and apparatuses for performing Free-Running Synthesis (FRS) and library preparation steps (e.g., nanopore library preparation) on a cartridge using digital microfluidics (DMF) in a tabletop DMF driver/reader apparatus.

Methods and apparatuses for performing Free-Running Synthesis (FRS) and library preparation steps (e.g., nanopore library preparation) on a cartridge using digital microfluidics (DMF) in a tabletop DMF driver/reader apparatus.

Provided herein are engineered variants of archaeal, prokaryotic, and eukaryotic polymerases that exhibit enhanced thermostability, enhanced incorporation of 3′ modified nucleotides, and improved uracil-tolerance, in polymerase-catalyzed nucleotide extension reactions relative to wild type polymerase enzymes. Also provided are uses of the engineered polymerases for forming complexed polymerases, forming binding complexes and forming ternary complexes, and uses for conducting nucleic acid sequencing reactions.