WO2024056038A1 - Hélicase de capif1 modifiée et son utilisation - Google Patents

Hélicase de capif1 modifiée et son utilisation Download PDF

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WO2024056038A1
WO2024056038A1 PCT/CN2023/118905 CN2023118905W WO2024056038A1 WO 2024056038 A1 WO2024056038 A1 WO 2024056038A1 CN 2023118905 W CN2023118905 W CN 2023118905W WO 2024056038 A1 WO2024056038 A1 WO 2024056038A1
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helicase
capif1
target polynucleotide
construct
seq
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谷天燕
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北京普译生物科技有限公司
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    • C12N15/63—Introduction of foreign genetic material using vectors; Vectors; Use of hosts therefor; Regulation of expression
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Definitions

  • the present invention relates to a modified CaPif1 helicase, in particular to a helicase that can control the movement of target polynucleotides through biological nanopores, and is particularly helpful in sequencing polynucleotides, and belongs to genetic engineering. and the field of genetic engineering.
  • Nanopore sequencing technology developed in recent years is a new type of single-molecule sequencing technology that uses electric field force to drive single-stranded polynucleotides through nanoscale biopore proteins embedded in insulating phospholipid membranes. Due to different bases size, each nucleotide molecule will generate a characteristic obstruction current when passing through the biological nanopore, and these characteristic current signals recorded correspond to the sequence of the target nucleic acid.
  • strand sequencing In the "strand sequencing” method, a single polynucleotide strand is passed through the biological nanopore to enable identification of the nucleotide sequence.
  • advantages of this sequencing technology are low cost, no need for PCR amplification, fast and real-time convenience, long sequencing reads (more than 150kb), and the ability to directly sequence RNA and epigenetic modifications. It is considered a revolutionary technology in the field of sequencing and has immeasurable application value.
  • nanopore sequencing technology also has serious limitations. Under the influence of an electric field, single-stranded polynucleotides pass through the nanopore so quickly that it is difficult to distinguish the current-blocking signal of a single nucleotide from the system noise. Therefore, to achieve identification of nucleotides, strand sequencing uses polynucleotide-bound molecular motors to control the movement of polynucleotides through the biological nanopore.
  • the combination of molecular motors and polynucleotides is not static. When controlling the movement of polynucleotides, especially when facing very long nucleotide sequences, the molecular motors may fall off from the polynucleotides.
  • the present invention overcomes the problem of too fast translocation speed of polynucleotides through nanopores in the prior art, and provides a DNA-dependent ATPase (CaPif1) helicase, which can Controlling polynucleotide punch movement is very useful.
  • CaPif1 DNA-dependent ATPase
  • the core of CaPif1 helicase contains five domains: 1A (RecA-like motor) domain, 2A (RecA-like motor) domain (RecA-like motor) domain, 1B (wedge domain) domain, 2B (SH3-like) domain and 2C domain (an additional structure unique to yeast).
  • the structural information of the corresponding CaPif1 (PDB:7OTJ) protein can be obtained from the Protein Data Bank (PDB).
  • the 1A and 2A domains are mainly involved in the binding and hydrolysis of ATP.
  • the 1B domain consists of a short helix and an extended loop structure, which is called the "wedge region".
  • the 2B domain adopts a SH-3-like folding manner, and the orbital-like ⁇ hairpin structure on it is close to the 1B domain.
  • the 2C domain has not yet been resolved in the crystal structure.
  • the present invention focuses on the two domains 1B and 2B, and tends to reduce or close the opening through covalent connection.
  • connection There are two ways of connection. One is through its own naturally occurring amino acids and the insertion of new amino acids, such as cysteine and unnatural amino acids, to achieve connection. The other is through linker molecules, which tend to connect cysteines. Linker molecules include: BMOE, Bis(PEG)2, Bis(PEG)3, etc.
  • the present invention introduces cysteine into the two structural domains 1B and 2B respectively.
  • the above-mentioned connecting molecules usually contain two functional terminals, which will be covalently connected to the cysteine to realize the connection of the two parts 1B and 2B, so that The bound polynucleotide will not dissociate from the helicase.
  • one aspect of the present invention provides a modified CaPif1 helicase, which modifies five natural cysteines in the amino acid sequence of wild-type CaPif1 (368-883). Cystine is C426, C507, C584, C592 and C662 respectively.
  • the five natural cysteines are replaced with alanine (A) or serine (S).
  • Another aspect of the present invention provides a modified CaPif1 helicase, which introduces new cysteine for connection, and the introduction sites include Q443, N448, K452, R455, I633, L634, P635, Q638, Q641, V642, D795, E796, D797 and T799.
  • preferred mutation combinations include R455C, E796C, C426A, C507A, C584A, C592A and C662A.
  • amino acid sequence of the helicase is shown in SEQ ID NO.1.
  • preferred mutation combinations include Q443C, L634C, C426A, C507A, C584A, C592A and C662A.
  • amino acid sequence of the helicase is shown in SEQ ID NO. 3.
  • the helicase binds to internal nucleotides of a single-stranded polynucleotide or a double-stranded polynucleotide.
  • Another aspect of the invention provides a nucleotide sequence encoding a helicase of the invention.
  • nucleotide sequence is shown in SEQ ID NO.2 or SEQ ID NO.4.
  • Another aspect of the present invention provides a complex formed between the helicase of the present invention and bismaleimidoethane or bismaleimide PEG3.
  • Another aspect of the invention provides a construct comprising a helicase according to the invention and a binding moiety for binding to a polynucleotide.
  • the binding moiety is selected from eukaryotic single-chain binding proteins, bacterial single-chain binding proteins, archaeal single-chain binding proteins, viral single-chain binding proteins, or double-chain binding proteins.
  • Another aspect of the present invention provides the helicase of the present invention or the nucleotide sequence encoding the helicase or the complex comprising the helicase or the construct comprising the helicase in characterizing the target polynucleoside. Application of acids or controlled passage of target polynucleotides through nanopores.
  • kits for characterizing a target polynucleotide or controlling the passage of a target polynucleotide through a nanopore comprising the helicase of the present invention or a nucleoside encoding the helicase. acid sequence or a complex comprising the helicase or a construct comprising the helicase.
  • Another aspect of the invention provides a device for characterizing a target polynucleotide or controlling the passage of a target polynucleotide through a nanopore, the device comprising the helicase of the invention or a nucleotide sequence encoding the helicase. or a complex containing the helicase or Constructs comprising said helicase.
  • Another aspect of the invention provides a method for characterizing a target polynucleotide or controlling the passage of a target polynucleotide through a nanopore, comprising the following steps:
  • the construct includes a helicase and a helicase for binding the polynucleotide the combined part.
  • said one or more characteristics are selected from the group consisting of origin, length, identity, sequence, secondary structure of the target polynucleotide or whether the target polynucleotide is modified.
  • said one or more characteristics are carried out by electrical measurements and/or optical measurements.
  • the target polynucleotide is single-stranded, double-stranded, or at least part of it is double-stranded.
  • the nanopores are transmembrane pores, and the transmembrane pores are biological pores, solid pores or hybrid pores between biology and solid.
  • Another aspect of the invention provides a vector comprising the nucleotide sequence of the helicase of the invention.
  • Yet another aspect of the present invention provides a host cell comprising a nucleotide sequence of the helicase of the present invention or a vector comprising the nucleotide sequence.
  • the present invention has demonstrated that the modified CaPif1 helicase can control the movement of polynucleotides through biological nanopores, especially under the action of electric field force.
  • the helicase enables target polynucleotides to move through the nanopore in a controlled and stepwise manner.
  • the specific CaPif1 helicase mutants provided by the present invention have improved ability to control the translocation of polynucleotides through nanopores. These mutants usually have one or more modifications on the 1B or 2B domain. . Therefore, the modified CaPif1 helicase provided by the present invention has at least one cysteine or unnatural amino acid inserted, and still maintains its ability to control the movement of polynucleotides.
  • the present invention also provides a modified CaPif1 helicase that covalently connects 1B and 2B domains through a linker molecule, which improves the stability of the CaPif1 helicase binding to polynucleotides, especially when polynucleotides are used.
  • the helicase of the present invention can still stably control the movement of the polynucleotide without falling off from the polynucleotide.
  • Figure 1 is a diagram showing the results of SDS-PAGE gel electrophoresis purification of the CaPif1 helicase of the present invention
  • Figure 2 is a schematic diagram of fluorescence analysis for detecting helicase enzyme activity.
  • Figure 3 is a graph showing the changes in fluorescence value generated by CaPif1 helicase unwinding the fluorescent substrate over time.
  • Figure 4 is an SDS-PAGE gel electrophoresis picture of the cross-linking results of the CaPif1 mutant.
  • Figure 5 is a gel shift image of CaPif1 binding to DNA before and after modification.
  • Figure 6 is a schematic diagram of DNA construct X used in the present invention.
  • H SEQ ID NO: 14 with a cholesterol tag at the 3’ end.
  • Figure 7 is a schematic diagram of DNA construct Y used in the present invention.
  • Figure 8 is a schematic diagram of the current trajectories of mutants CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A-bismaleimidoethane when controlling the movement of the complete DNA construct X through the nanopore.
  • Figure 9 is an enlarged view of an area showing the movement of the DNA construct X via the helicase shown in Figure 8.
  • Figure 10 is a schematic diagram of the current trajectory when CaPif1 helicase controls the displacement of DNA construct X through the nanopore.
  • Figure 11 is an enlarged view of an area showing the movement of the via hole of DNA construct X controlled by the helicase shown in Figure 10.
  • the recombinant plasmid was transformed into the BL21(DE3) E. coli expression host by heat shock method.
  • the host bacteria containing the expression plasmid were first cultured overnight at 37°C in LB medium with kana resistance, and then amplified and cultured at 37°C at a ratio of 1:100, until the OD (600 ) value reaches 0.4-0.6, stop culturing and place it at 4°C for 1 hour of cooling treatment, then add isopropyl ⁇ -D-Thiogalactoside (IPTG) at a final concentration of 0.5mM to induce expression at 16°C12 -16h.
  • IPTG isopropyl ⁇ -D-Thiogalactoside
  • Figure 1 shows the SDS-PAGE gel electrophoresis pattern of purified CaPif1 helicase.
  • Example 2 Fluorescence experiment to analyze the unwinding activity of CaPif1 helicase
  • Figure 2 is a schematic diagram of fluorescence analysis for detecting helicase enzyme activity.
  • the fluorescent substrate chain (final concentration 100 nM, d, SEQ ID NO: 6) has a single-stranded DNA portion of 20 bases at the 5' end and a double-stranded DNA portion of 18 bases hybridized, and its 3' end has a fluorescent group (Cy3, f).
  • BHQ-1, e fluorescent quenching group
  • CaPif1 helicase will bind to the 5'-end single-stranded DNA portion of the fluorescent substrate, and after adding ATP (2mM) and MgCl 2 (2mM), Shift in the 5'-3' direction and unwind the double-stranded portion.
  • the excess capture chain (b, SEQ ID NO: 8) is preferentially complementary to the short chain (c) to prevent re-annealing between the initial substrates, and the released substrates
  • the substance backbone (d) emits fluorescence.
  • Figure 3 shows the change in fluorescence value generated by the unwinding of the fluorescent substrate by CaPif1 helicase over time in a 300mM NaCl buffer (25mM Tris-HCl pH 7.5, 2mM ATP, 2mM MgCl 2 , 300mM NaCl). The results show that the substrate ranges from essentially non-fluorescent to fluorescent.
  • Example 3 Preparation of CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A mutation combinations and CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A and C662A mutation combinations
  • CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A are SEQ ID NO: 1 and bismaleimidoethane with mutation combinations R455C, E796C, C426A, C507A, C584A, C592A and 662A. Alkane connection;
  • CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A and C662A is SEQ ID NO: 3 with the mutation combination Q443C, L634C, C426A, C507A, C584A, C592A and C662A linked to bismaleimide PEG3.
  • the recombinant expression plasmid of CaPif1 helicase was finally obtained. Then, site-directed mutagenesis was performed by overlapping PCR to obtain the nucleic acid sequences encoding mutation combinations R455C, E796C, C426A, C507A, C584A, C592A, and 662A (SEQ ID NO. 2). and the nucleic acid sequence encoding mutation combinations Q443C, L634C, C426A, C507A, C584A, C592A and C662A (SEQ ID NO. 4).
  • the mutated recombinant plasmid was transformed into the BL21 (DE3) E. coli expression host by heat shock method.
  • the host bacteria containing the expression plasmid were first cultured overnight at 37°C in LB medium with kana resistance, and then amplified and cultured at 37°C at a ratio of 1:100, until the OD (600 ) value reaches 0.4-0.6, stop culturing and place it at 4°C for 1 hour of cooling treatment, then add isopropyl ⁇ -D-Thiogalactoside (IPTG) at a final concentration of 0.5mM to induce expression at 16°C12 -16h.
  • IPTG isopropyl ⁇ -D-Thiogalactoside
  • the buffer was replaced with PBS buffer (pH7.5) through a 0.5ml Zeba desalting column (7k MWCO) to obtain a 100 ⁇ l sample.
  • PBS buffer pH7.5
  • Zeba desalting column 7k MWCO
  • Cross-linking results were analyzed on a 4-10% polyacrylamide gel.
  • Example 4 Using gel shift assay to measure the ability of modified CaPif1 helicase to bind DNA
  • the DNA substrate required for gel shift experiments was prepared by annealing (SEQ ID NO: 9 was hybridized with SEQ ID NO: 10 containing a 5' end Cy3 label), and then it was mixed with SEQ ID NO: 10 in a molar ratio of 1:1.
  • Wild-type CaPif1 (PDB ID: 7OTJ, related website: RCSB PDB-7OTJ: Crystal structure of Pif1 helicase from Candida albicans), CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A (with mutation combinations R455C, E796C, SEQ ID NO: 1) for C426A, C507A, C584A, C592A and C662A and CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A and C662A (with mutation combination Q443C, L634C, C426A, C507A, C584A, C592 A and C662A SEQ ID NO: 3) Incubate in buffer (25mM Tris-HCl pH 7.5, 300mM NaCl) for one hour at room temperature to obtain a final concentration of CaP
  • Example 5 CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A-Bismaleimidoethane and CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A and C662A-Bismaleimidoethane Imine PEG3 has the ability to control the passage of intact DNA constructs through nanopores ability to move
  • CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A-bismaleimidoethane are SEQ ID NO: 1 with mutation combination R455C, E796C, C426A, C507A, C584A, C592A and C662A.
  • CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A, and C662A-Bismaleimide PEG3 is a protein with mutations Q443C, L634C, C426A, C507A, C584A, C592A, and SEQ ID NO: 3 of C662A is linked to bismaleimide PEG3.
  • DNA construct X as shown in Figure 6 was prepared.
  • design primers which contain sequences A, C, D, E, and F, and then use them to amplify a 1000-base sequence (G) on lambda DNA.
  • the obtained PCR product is purified and matched with sequence H at a ratio of 1:1.1 Annealing hybridization is performed at the molar ratio to obtain the final DNA construct X.
  • the prepared DNA construct C507A, C584A, C592A, and C662A-bismaleimide PEG3 (final concentration 10 nM) were preincubated in buffer (10 mM Hepes, pH 8.0, 100 Mm KCl, 10% glycerol) for 30 min at room temperature.
  • buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0
  • phospholipids embedded in the DPhPC phospholipid bilayer were Electrical signal measurements were obtained from Csgg nanopores.
  • 2 ml buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0 ) is flowed through the system to remove residual excess nanopores.
  • the pre-incubated sample, ATP (final concentration 2mM) and MgCl 2 (final concentration 10mM) were then flowed together into a single nanopore experimental system (total volume 100 ⁇ L), and the signal was measured at a constant voltage of +180mV for 6h (including potential 2s -180mV voltage inversion).
  • Figure 9 shows an enlarged view of part of the region where CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A mutants control DNA movement.
  • Example 6 CaPif1 helicase controls movement of entire DNA construct X through a single Csgg nanopore
  • This example takes CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A (SEQ ID NO: 1 with mutation combination R455C, E796C, C426A, C507A, C584A, C592A and C662A) as an example to verify CaPif1 unwinding How the enzyme controls the movement of the entire DNA construct X through a single Csgg nanopore.
  • DNA construct X as shown in Figure 6 was prepared.
  • design primers which contain sequences A, C, D, E, and F, and then use them to amplify a 1000-base sequence (G) on lambda DNA.
  • the obtained PCR product is purified and matched with sequence H at a ratio of 1:1.1 Annealing hybridization is performed at the molar ratio to obtain the final DNA construct X.
  • buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0
  • phospholipids embedded in the DPhPC phospholipid bilayer were Electrical signal measurements were obtained from Csgg nanopores.
  • 2 ml buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0 ) is flowed through the system to remove residual excess nanopores.
  • the pre-incubated sample, ATP (final concentration 2mM) and MgCl 2 (final concentration 10mM) were then flowed together into a single nanopore experimental system (total volume 100 ⁇ L), and the signal was measured at a constant voltage of +180mV for 6h (including potential 2s -180mV voltage inversion).
  • CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A (SEQ ID NO: 1 with mutation combination R455C, E796C, C426A, C507A, C584A, C592A and C662A) was observed to unwind
  • the enzyme controls the movement of DNA construct X through the nanopore.
  • the duration of helicase-controlled DNA movement of 14 seconds corresponds to the movement of nearly 1000 bp of DNA construct through the Csgg nanopore.
  • Figure 11 shows CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A (SEQ ID NO: 1 with mutation combination R455C, E796C, C426A, C507A, C584A, C592A and C662A) helicase control A magnified view of part of the DNA movement.
  • Example 7 Ability of wild-type CaPifl and CaPifl-R455C, E796C, C426A, C507A, C584A, C592A and C662A-bismaleimidoethane to control movement of intact DNA construct Y through the nanopore
  • CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A-bismaleimidoethane are SEQ ID NO: 1 with mutation combination R455C, E796C, C426A, C507A, C584A, C592A and C662A. Connected with bismaleimidoethane.
  • DNA construct Y as shown in Figure 7 was prepared.
  • the upstream primer contains A, C, D, E and J sequences.
  • the J sequence is as shown in SEQ ID NO:16
  • the downstream primer is as shown in SEQ ID NO:17.
  • They were then used to amplify the 4115 base length sequence (K) on ⁇ DNA, so that a poly T sequence (I) was added to the 3' end of the K sequence (shown as SEQ ID NO: 15), and the obtained After purification, the PCR product is annealed and hybridized with sequence H at a molar ratio of 1:1.1 to obtain the final DNA construct Y.
  • the prepared DNA construct Y (final concentration 0.1nM) was combined with wild-type CaPif1 (PDB ID: 7OTJ, related website: RCSB PDB-7OTJ: Crystal structure of Pif1 helicase from Candida albicans) and CaPif1-R455C, E796C, C426A respectively.
  • C507A, C584A, C592A, and C662A-bismaleimidoethane final concentration 10 nM were preincubated in buffer (10mM Hepes, pH 8.0, 100mM KCl, 10% glycerol) at room temperature for 30 minutes.
  • buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0
  • phospholipids embedded in the DPhPC phospholipid bilayer were Electrical signal measurements were obtained from Csgg nanopores.
  • 2 ml buffer 600mM KCl, 75mM K 3 [Fe(CN) 6 , 25mM K 4 [Fe(CN) 6 ] ⁇ 3H 2 O, 100mM Hepes, pH 8.0 ) is flowed through the system to remove residual excess nanopores.
  • the pre-incubated sample, ATP (final concentration 2mM) and MgCl 2 (final concentration 10mM) were then flowed together into a single nanopore experimental system (total volume 100 ⁇ L), and the signal was measured at a constant voltage of +180mV for 6h (including potential 2s -180mV voltage inversion).
  • the results show that adding the complex formed by CaPif1 helicase and DNA construct to the Csgg nanopore system can generate a typical nucleic acid through-hole current signal.
  • the wild-type CaPif1 helicase monomer and CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A-bismaleimidoethane can control the pore movement of DNA construct Y.
  • SEQ ID NO: 1 which is the amino acid sequence of CaPif1-R455C, E796C, C426A, C507A, C584A, C592A and C662A mutants. The specific sequence is:
  • SEQ ID NO: 2 which is the coding sequence of SEQ ID NO: 1.
  • the specific sequence is:
  • SEQ ID NO: 3 which is the amino acid sequence of CaPif1-Q443C, L634C, C426A, C507A, C584A, C592A and C662A mutants.
  • the specific sequence is:
  • SEQ ID NO: 4 which is the coding sequence of SEQ ID NO: 3.
  • the specific sequence is:
  • SEQ ID NO: 5 which is the optimized nucleic acid sequence of CaPif1 protein. The specific sequence is:
  • SEQ ID NO: 6 which is the sequence of the fluorescent substrate chain. The specific sequence is:
  • SEQ ID NO: 7 which is a short chain sequence that is complementary to the fluorescent substrate chain sequence.
  • the specific sequence is:
  • SEQ ID NO: 8 which is the capture strand sequence.
  • the specific sequence is:
  • SEQ ID NO: 9 which is the DNA substrate sequence.
  • the specific sequence is:
  • SEQ ID NO: 10 which is a sequence that hybridizes with SEQ ID NO: 9. The specific sequence is:
  • SEQ ID NO: 11 which is the D sequence of DNA construct X and construct Y. The specific sequence is:
  • SEQ ID NO: 12 which is the F sequence of DNA construct X and construct Y. The specific sequence is:
  • SEQ ID NO: 13 which is the G sequence of DNA construct X. The specific sequence is:
  • SEQ ID NO: 14 which is the H sequence of DNA construct X. The specific sequence is:
  • SEQ ID NO: 15 which is the K sequence of DNA construct Y.
  • the specific sequence is:
  • SEQ ID NO: 16 which is the J sequence of DNA construct Y. The specific sequence is:
  • SEQ ID NO: 17 which is the downstream primer sequence of DNA construct Y.
  • the specific sequence is:

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Abstract

La présente invention appartient au domaine du génie génétique et a pour objet une hélicase CaPif1 modifiée, un complexe comprenant l'hélicase, une construction comprenant l'hélicase, un procédé d'utilisation de l'hélicase ou du complexe ou de la construction pour représenter un polynucléotide cible, et une utilisation associée. L'hélicase CaPif1 modifiée, le complexe et sa construction peuvent tous réguler le mouvement d'un polynucléotide lors de son passage à travers un nanopore biologique. En particulier lorsque la longueur d'une chaîne polynucléotidique est augmentée, l'hélicase CaPif1 modifiée, le complexe et sa construction peuvent toujours réguler de manière stable le déplacement du polynucléotide sans se détacher du polynucléotide. La présente invention concerne également un mutant spécifique de l'hélicase CaPif1, permettant d'améliorer sa capacité à réguler le déplacement du polynucléotide lors de son passage à travers le nanopore.
PCT/CN2023/118905 2022-09-16 2023-09-14 Hélicase de capif1 modifiée et son utilisation WO2024056038A1 (fr)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20150191709A1 (en) * 2012-07-19 2015-07-09 Oxford Nanopore Technologies Limited Modified helicases
US20160257942A1 (en) * 2013-10-18 2016-09-08 Oxford Nanopore Technologies Ltd. Modified helicases
CN107109380A (zh) * 2014-10-07 2017-08-29 牛津纳米孔技术公司 经修饰的酶
WO2021253410A1 (fr) * 2020-06-19 2021-12-23 北京齐碳科技有限公司 Hélicase de type pif1 et utilisation associée
CN113930406A (zh) * 2021-12-17 2022-01-14 北京齐碳科技有限公司 一种Pif1-like解旋酶及其应用
WO2022126304A1 (fr) * 2020-12-14 2022-06-23 北京齐碳科技有限公司 Hélicase modifiée et son application

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Publication number Priority date Publication date Assignee Title
CN100381466C (zh) * 2004-04-06 2008-04-16 中国科学院上海生命科学研究院 一种人Pif1基因、其编码蛋白及其应用

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US20150191709A1 (en) * 2012-07-19 2015-07-09 Oxford Nanopore Technologies Limited Modified helicases
US20160257942A1 (en) * 2013-10-18 2016-09-08 Oxford Nanopore Technologies Ltd. Modified helicases
CN107109380A (zh) * 2014-10-07 2017-08-29 牛津纳米孔技术公司 经修饰的酶
WO2021253410A1 (fr) * 2020-06-19 2021-12-23 北京齐碳科技有限公司 Hélicase de type pif1 et utilisation associée
WO2022126304A1 (fr) * 2020-12-14 2022-06-23 北京齐碳科技有限公司 Hélicase modifiée et son application
CN113930406A (zh) * 2021-12-17 2022-01-14 北京齐碳科技有限公司 一种Pif1-like解旋酶及其应用

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Title
LU, K. Y. ET AL.: "Structural study of the function of Candida Albicans Pif1", BIOCHEMICAL AND BIOPHYSICAL RESEARCH COMMUNICATIONS, vol. 567, 21 June 2021 (2021-06-21), XP086694340, DOI: 10.1016/j.bbrc.2021.06.050 *

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