Provided herein is a polymerase-free enzyme mix (FRAG) for fragmenting double-stranded DNA. In some embodiments the enzyme mix may comprise a double-stranded DNA nickase and at least one of a DNA ligase capable of sealing a nick within a DNA, and a single-strand specific DNA nuclease. Methods for fragmenting double-stranded DNA are also provided.

Methods and compositions are described herein for primer extension target enrichment of immune receptor (BCR or TCR) sequences.

Methods and compositions are described herein for primer extension target enrichment of immune receptor (BCR or TCR) sequences.

Rapid methods, capable of being performed in a single reaction tube, are described herein for constructing libraries for high-throughput polynucleotide sequencing applications, such as next generation sequencing (NGS) applications. Oligonucleotide probes include chemically-active groups at their 5′ or 3′ ends, or both, to facilitate the cleavage of their 5′ or 3′ ends, or both, following their hybridization to the single-stranded ends of frayed template fragments. Cleavage of probe ends reveal single-stranded regions at the ends of the hybridized fragments. Adaptors, specific to these ends, are ligated to the hybridized probe/template fragments, and blunt end fragments are ligated to blunt ends of hybridized probe/template fragments, if present, to generate the adaptor-ligated fragments of the library.

Rapid methods, capable of being performed in a single reaction tube, are described herein for constructing libraries for high-throughput polynucleotide sequencing applications, such as next generation sequencing (NGS) applications. Oligonucleotide probes include chemically-active groups at their 5′ or 3′ ends, or both, to facilitate the cleavage of their 5′ or 3′ ends, or both, following their hybridization to the single-stranded ends of frayed template fragments. Cleavage of probe ends reveal single-stranded regions at the ends of the hybridized fragments. Adaptors, specific to these ends, are ligated to the hybridized probe/template fragments, and blunt end fragments are ligated to blunt ends of hybridized probe/template fragments, if present, to generate the adaptor-ligated fragments of the library.

The present disclosure discloses an antibody fragment library, method for preparing the library and its applications. The essential steps in construction of the library is devoid of any restriction enzyme. Emulsion based PCR has been used as an important tool for the construction and validation of the library. The method as disclosed in the present disclosure leads to construction of a library comprising at least 8 billion clones.

The present disclosure discloses an antibody fragment library, method for preparing the library and its applications. The essential steps in construction of the library is devoid of any restriction enzyme. Emulsion based PCR has been used as an important tool for the construction and validation of the library. The method as disclosed in the present disclosure leads to construction of a library comprising at least 8 billion clones.

Provided are a nucleic acid library construction method and an application thereof in the analysis of an abnormal chromosomal structure of a preimplantation embryo. Enzymatic cleavage is performed by means of combining a first endonuclease and a second endonuclease to capture a DNA sequence within a fixed fragment range. The specific sequences captured are then sequenced. When the average genome sequencing depth is greater than or equal to 3×, an SNP analysis can be performed in the entire range of the genome in order to perform detection of balanced translocation of the embryo and the like by means of a linkage analysis of a family-line sample.

Methods and compositions are provided for amplifying a pool of oligonucleotides, such as dual guide oligonucleotide constructs comprising sequences encoding a first guide RNA segment and a sequence encoding a second guide RNA segment. An amplification mixture is formed comprising the pool of oligonucleotides, an amplification enzyme, deoxyribonucleotide triphosphates, and primers. The amplification mixture is thermocycled a sufficient number of times and under conditions to produce a library of oligonucleotide constructs. The present methods and compositions provide dual guide libraries, including libraries that are essentially free of scrambled library members.

Mutated phosphotriesterase-like lactonases or functional fragments can be used in methods for treating or preventing infection of a bacterium in a host, such as a plant or a part, organ or a plant propagation material. The methods include applying the mutated phosphotriesterase-like lactonases or the wild-type enzyme to the host Cells expressing the mutated phosphotriesterase-like lactonases can also be produced using nucleic acid molecules and vectors encoding the mutated phosphotriesterase-like lactonases or functional fragments.