Abstract: Provided are an adaptor element in a bubble shape, a method of constructing a sequencing library with such an adapter element. The adaptor element is a hybrid formed with a long-chain nucleic acid A and a short-chain nucleic acid B. The hybrid is in the bubble shape with paired regions at two terminals and a non-paired region in the middle.

Abstract: Provided are a phi29 DNA polymerase and an encoding gene and an application thereof. The phi29 DNA polymerase is C1) or C2): C1) is a protein with DNA polymerase activity obtained by substituting at least one of the 58th, 61st, 94th, 96th, 119th, and 155th amino acid residues in the amino acid sequence of a wild type phi29 DNA polymerase as shown in SEQ ID NO: 2 in the sequence listing; and C2) is a fusion protein obtained by linking a label to the N-terminus and/or C-terminus of the protein represented by C1). A 3?-5?exonuclease of the phi29 DNA polymerase has activity lower than that of the wild type phi29 DNA polymerase, and can efficiently and continuously synthesize DNA during amplification and sequencing.

Abstract: Disclosed in the present disclosure is a recombinant DNA polymerase. The recombinant DNA polymerase is any one selected from: A) a protein, having amino acid modifications at positions 408, 409 and 485, and at least one of amino acid modification(s) at positions 53, 59, 199, 243, 526, 558, 613, 641, 671, 673, 674, 692 and 709 compared to the amino acid sequence of a wild-type KOD DNA polymerase; B) a protein derived from the protein in A), formed by deleting amino acids 1 to 29 from a C-terminus of the protein in A) and keeping the remaining amino acids unchanged; and C) a protein derived from the protein in A) or B), formed by connecting a tag to the N-terminus or C-terminus of the amino acid sequence of the protein in A) or B), wherein the protein in A), B) and C) has DNA polymerase activity.

Abstract: The present invention provides a method for sequencing a nucleic acid using an immersion reaction protocol. The immersion reaction protocol comprises sequentially immersing a solid support having nucleic acid molecules immobilized thereon in different reaction containers to realize nucleic acid sequencing.

Abstract: Disclosed is a method for obtaining a single-cell mRNA sequence. The method of the present invention comprises: (1) capturing mRNA of a cell by using a cell tag carrier, and performing reverse transcription to obtain cDNA having a cell tag, cDNAs from the same cell having the same cell tag, and cDNAs from different cells having different cell tags; (2) obtaining multiple cDNA fragments having molecular tags by using a transposase complex and a molecular tag carrier, the fragments from the same cDNA having the same molecular tag, and the fragments from different cDNAs having different molecular tags; (3) performing high-throughput sequencing; (4) performing sequence assembly according to the molecular tags to obtain the sequence of each mRNA; and obtaining the sequence of all mRNAs of each single cell according to the cell tags. The method provided by the present invention can be used for obtaining the sequence of all mRNAs of each of a large number of single cells by means of high throughput.

Abstract: A nucleic acid probe and a nucleic acid sequencing method for performing sequencing while ligating nucleic acids. The nucleic acid probe is a DNA sequencing probe, comprising a first moiety, a second moiety, a linker, and a detectable label. A base of the first moiety is A, T, U, C, or G, a base of the second moiety is a random base and/or a universal base, and 3 bases or more are present in the second moiety. The first moiety and the second moiety are ligated via the linker, the connection between the first moiety and the ligation can be cleaved, and the detectable label is ligated to the second moiety or the linker. The above probe, a combination formed therewith, or a sequencing method using the same can reduce the number or types of probes in nucleic acid sequencing, thereby reducing cost.

Abstract: The present invention provides a method for improving the loading of nucleic acid on a solid support by contacting the solid support with a poloxamer-containing reagent. The present invention also provides a method for improving the stability of a nucleic acid on a solid support, comprising contacting a nucleic acid molecule with a partially double-strand oligonucleotide before or after loading the nucleic acid molecule on a solid support, so as to cause the nucleic acid molecule to hybridize with the oligonucleotide. The present invention also provides a combined use of the two methods.

Abstract: Provided are a group of phi29 DNA polymerase mutants having increased thermal stability and use thereof. The phi29 DNA polymerase mutants are proteins obtained by performing point mutation A and/or point mutation B and/or point mutation C on phi29 DNA polymerase, the point mutation A meaning that an amino acid residue M at position 97 of the phi29 DNA polymerase is mutated to other amino acid residue, the point mutation B meaning that an amino acid residue L at position 123 of the phi29 DNA polymerase is mutated into other amino acid residue, and the point mutation C meaning that an amino acid residue E at position 515 of the phi29 DNA polymerase is mutated to other amino acid residue. The stability of the phi29 DNA polymerase mutants is higher than that of a wild-type phi29 DNA polymerase.

Abstract: Improved single molecule sequencing methods, compositions, and devices, are provided. In a first aspect, the present invention provides a multi-pass method of sequencing a target sequence using nanopore sequencing, the method comprising: i) providing a non-naturally occurring concatemer nucleic acid molecule comprising a plurality of copies of the target sequence; ii) nanopore sequencing at least three copies of the target sequence in the concatemer, thereby obtaining a multi-pass sequence dataset, wherein the multi-pass sequence dataset comprises target sequence datasets for the at least three copies of the target sequence; and iii) using the multi-pass sequence dataset to determine the target sequence.

Abstract: Provided are a phi29 DNA polymerase mutant with increased thermo stability, a method for preparing the mutant, the use of the mutant, and a method for increasing the stability of the phi29 DNA polymerase.

Abstract: Provided are a vesicular adaptor and a single-chain cyclic library constructed by using the adaptor. The library can be used for RNA sequencing and other sequencing platforms dependent on a single-stranded cyclic library, and has the advantage of high throughput sequencing, high accuracy and simple operations.

Abstract: The present invention provides a primer for nucleic acid random fragmentation and a nucleic acid random fragmentation method. The primer consists of a plurality of upstream random primers and downstream random primers. The sequence composition of the upstream random primers is 5?-X-Y-3?, and the sequence composition of the downstream random primers is 5?-P-Y?-X?-close-3?, wherein Y and Y? are random sequences, X is all or part of sequences of a sequencing platform 5? end adaptor, X? is all or part of sequences of a sequencing platform 3? end adaptor, P is phosphorylation modification, and close is close modification. The primer of the present invention adopts double random anchoring of both the upstream random primers and the downstream random primers, and a DNA sample can be randomly broken.

Abstract: Provided are a phi29 DNA polymerase and an encoding gene and an application thereof. The phi29 DNA polymerase is C1) or C2): C1) is a protein with DNA polymerase activity obtained by substituting at least one of the 58th, 61st, 94th, 96th, 119th, and 155th amino acid residues in the amino acid sequence of a wild type phi29 DNA polymerase as shown in SEQ ID NO: 2 in the sequence listing; and C2) is a fusion protein obtained by linking a label to the N-terminus and/or C-terminus of the protein represented by C1). A 3?-5?exonuclease of the phi29 DNA polymerase has activity lower than that of the wild type phi29 DNA polymerase, and can efficiently and continuously synthesize DNA during amplification and sequencing.

Abstract: Provided are a vesicular linker and a single-chain cyclic library constructed by using the linker. The library can be used for RNA sequencing and other sequencing platforms dependent on a single-stranded cyclic library, and has the advantages of high throughput sequencing, high accuracy and simple operations.

Abstract: Provided is a linker element and a method of using the linker element to construct a sequencing library, wherein the linker element consists of a linker A and a linker B, the linker A is obtained through the complementary pairing of a long nucleic acid strand and a short nucleic acid strand, the 5? end of the long strand has a phosphoric acid modification, and the 3? end of the short strand has an enclosed modification, with enzyme sites in the short strand; and the linker B is a nucleic acid single strand, and the 3? end thereof can be in a complementary pairing with the 5? end of the long strand of the linker A. Using the linker element of the present invention for constructing a sequencing library ensures the linking directionality of the linkers while solving the problems of fragment interlinking, linker self-linking and low linking efficiency, and reducing the purification reaction between steps, shortening the linking time and reducing costs.

Abstract: A method and reagent for constructing a nucleic acid double-linker single-strand cyclic library.

Abstract: Disclosed in the present disclosure is a recombinant DNA polymerase. The recombinant DNA polymerase is any one selected from: A) a protein, having amino acid modifications at positions 408, 409 and 485, and at least one of amino acid modification(s) at positions 53, 59, 199, 243, 526, 558, 613, 641, 671, 673, 674, 692 and 709 compared to the amino acid sequence of a wild-type KOD DNA polymerase; B) a protein derived from the protein in A), formed by deleting amino acids 1 to 29 from a C-terminus of the protein in A) and keeping the remaining amino acids unchanged; and C) a protein derived from the protein in A) or B), formed by connecting a tag to the N-terminus or C-terminus of the amino acid sequence of the protein in A) or B), wherein the protein in A), B) and C) has DNA polymerase activity.

Abstract: Provided is a single fluorescent dye based sequencing method. Moreover, the present invention further provide modified nucleosides and nucleotides, and a kit comprising the nucleoside and/or nucleotide, particularly suitable for the sequencing method of the present invention. Additionally, the present invention further provides uses of the nucleoside, the nucleotide and the kit for sequencing.

Abstract: Provided is a method of constructing a sequencing library. The method includes 1) providing a single-stranded DNA fragment from a biological sample; 2) subjecting the single-stranded DNA fragment to whole genomic amplification to obtain a whole genome amplification product; 3) fragmenting the whole genome amplification product using a transposase embedded with two adaptors to obtain a fragmented product with two adaptors respectively at two ends; and 4) amplifying the fragmented product with two adaptors respectively at two ends using a tag sequence and a pair of primers to obtain said sequencing library.

Abstract: Provided are a method for constructing a nucleic acid single-stranded cyclic library and the reagents used therein. By the combination of interruption via a transposase with a restricted nick translation reaction, the method realizes a simple and rapid nucleic acid single-stranded cyclic library construction.