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US5521077A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of generating multiple protein variants and populations of protein variants prepared thereby

Assignee: Leland Stanford Junior University
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Filing: 1994-04-28
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Granted: 1996-05-28
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Expires: 2014-04-28
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Abstract

Abstract A method based on generalized recombination is provided for generating multiple protein variants. The method involves introducing into host cells at least two pools of mutant encoding nucleotide sequences, recipient and donor, transducing the donor pool into the recipient cells and subsequently screening and selecting the recombinants thereby produced for expressed proteins exhibiting desired characteristics. A population of such protein variants is also provided.

Inventors

  • 👤 Chaitan Khosla
  • 👤 Robert Caren

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-04 02:51
CPC Classifications
C; C12; C12N; C12N15/00; C12N15/09; C12N15/10; C12N15/1034; C12N15/1093; C12N9/00; C12N9/0004; C12N9/0012; C12N9/0026; C12N9/0028; C12N9/003

Claims Analysis

Total Claims: 28
Claim 1
Independent Claim 208 words
A method of generating multiple protein variants, wherein said method comprises: a) providing first and second sets of allelic mutants, wherein said first set of allelic mutants comprises at least one recipient pool of mutant encoding nucleotide sequences and said second set of allelic mutants comprises at least one donor pool of mutant encoding nucleotide sequences; b) cloning each recipient pool of mutant encoding nucleotide sequences into a recipient vector; c) transforming or transducing the recipient vector into a host cell to generate a pool of recipient cells; d) cloning each donor pool of mutant encoding nucleotide sequences into a donor vector selected from the group consisting of phagemids and cosmids; e) transforming or transducing the donor vector into a host cell to generate a pool of donor cells; f) infecting the pool of donor cells with a helper phage to generate a mixture of donor phage particles, wherein said mixture comprises donor phage particles which contain said helper phage genome and phage particles which contain donor vectors having a mutant encoding nucleotide sequence; g) clonally amplifying the pools of donor phage and recipient cells; and h) transducing the recipient cells with the mixture of donor phage particles to generate a set of recombinants; i) screening the recombinants.
Claim 2
Independent Claim 208 words
A method of generating multiple protein variants, wherein said method comprises: a) providing first and second sets of allelic mutants, wherein said first set of allelic mutants comprises at least one recipient pool of mutant encoding nucleotide sequences and said second set of allelic mutants comprises at least one donor pool of mutant encoding nucleotide sequences; b) cloning each recipient pool of mutant encoding nucleotide sequences into a recipient vector; c) transforming or transducing the recipient vector into a host cell to generate a pool of recipient cells; d) cloning each donor pool of mutant encoding nucleotide sequences into a donor vector selected from the group consisting of phagemids and cosmids; e) transforming or transducing the donor vector into a host cell to generate a pool of donor cells; f) infecting the pool of donor cells with a helper phage to generate a mixture of donor phage particles, wherein said mixture comprises donor phage particles which contain said helper phage genome and phage particles which contain donor vectors having a mutant encoding nucleotide sequence; g) clonally amplifying the pools of donor phage and recipient cells; and h) transducing the recipient cells with the mixture of donor phage particles to generate a set of recombinants; i) screening the recombinants.
Claim 3
Dependent Claim 12 words
The method of claim 1, wherein the donor vector is a phagemid.
Claim 4
Dependent Claim 12 words
The method of claim 2, wherein the host cell is a bacterium.
Claim 5
Dependent Claim 11 words
The method of claim 3, wherein the bacterium is Escherichia coli.
Claim 6
Dependent Claim 29 words
The method of claim 2, further comprising separating phage particles which contain a helper phage genome from phage particles which contain a phagemid having a mutant encoding nucleotide sequence.
Claim 7
Dependent Claim 28 words
The method of claim 5, wherein the phage particles which contain a helper phage genome are separated from the phage particles which contain a phagemid by size difference.
Claim 8
Dependent Claim 27 words
The method of claim 2, further comprising maintaining a multiplicity of infection of at least one and a transductant-forming-unit to plaque-forming-unit ratio (tfu/pfu) of at least one.
Claim 9
Dependent Claim 14 words
The method of claim 2, wherein each recipient vector expresses a distinct genetic marker.
Claim 10
Dependent Claim 22 words
The method of claim 2, further comprising repeating steps (c) to (i) using additional cloned donor pools of mutant encoding nucleotide sequences.
Claim 11
Dependent Claim 13 words
The method of claim 2, wherein each phagemid expresses a distinct genetic marker.
Claim 12
Dependent Claim 13 words
The method of claim 2, wherein the helper phage is a filamentous phage.
Claim 13
Dependent Claim 11 words
The method of claim 11, wherein the filamentous phage is M13.
Claim 14
Dependent Claim 10 words
The method of claim 1, further comprising screening intermediate populations.
Claim 15
Dependent Claim 211 words
A population of multiple protein variants prepared by a process comprising the steps of: a) providing first and second sets of allelic mutants, wherein said first set of allelic mutants comprises at least one recipient pool of mutant encoding nucleotide sequences and said second set of allelic mutants comprises at least one donor pool of mutant encoding nucleotide sequences; b) cloning each recipient pool of mutant encoding nucleotide sequences into a recipient vector; c) transforming or transducing the recipient vector into a host cell to generate a pool of recipient cells; d) cloning each donor pool of mutant encoding nucleotide sequences into a donor vector selected from the group consisting of phagemids and cosmids; e) transforming or transducing the donor vector into a host cell to generate a pool of donor cells; f) infecting the pool of donor cells with a helper phage to generate a mixture of donor phage particles, wherein said mixture comprises donor phage particles which contain said helper phage genome and phage particles which contain donor vectors having a mutant encoding nucleotide sequence; g) clonally amplifying the pools of donor phage and recipient cells; h) transducing the recipient cells with the mixture of donor phage particles to generate a set of recombinants; and i) screening the recombinants.
Claim 16
Dependent Claim 211 words
A population of multiple protein variants prepared by a process comprising the steps of: a) providing first and second sets of allelic mutants, wherein said first set of allelic mutants comprises at least one recipient pool of mutant encoding nucleotide sequences and said second set of allelic mutants comprises at least one donor pool of mutant encoding nucleotide sequences; b) cloning each recipient pool of mutant encoding nucleotide sequences into a recipient vector; c) transforming or transducing the recipient vector into a host cell to generate a pool of recipient cells; d) cloning each donor pool of mutant encoding nucleotide sequences into a donor vector selected from the group consisting of phagemids and cosmids; e) transforming or transducing the donor vector into a host cell to generate a pool of donor cells; f) infecting the pool of donor cells with a helper phage to generate a mixture of donor phage particles, wherein said mixture comprises donor phage particles which contain said helper phage genome and phage particles which contain donor vectors having a mutant encoding nucleotide sequence; g) clonally amplifying the pools of donor phage and recipient cells; h) transducing the recipient cells with the mixture of donor phage particles to generate a set of recombinants; and i) screening the recombinants.
Claim 17
Dependent Claim 16 words
The population of claim 14, prepared by the process wherein the donor vector is a phagemid.
Claim 18
Dependent Claim 16 words
The population of claim 15, prepared by the process wherein the host cell is a bacterium.
Claim 19
Dependent Claim 15 words
The population of claim 16, prepared by the process wherein the bacterium is Escherichia coli.
Claim 20
Dependent Claim 33 words
The population of claim 15, prepared by the process further comprising separating phage particles which contain a helper phage genome from phage particles which contain a phagemid having a mutant encoding nucleotide sequence.
Claim 21
Dependent Claim 32 words
The population of claim 18, prepared by the process wherein the phage particles which contain a helper phage genome are separated from the phage particles which contain a phagemid by size difference.
Claim 22
Dependent Claim 31 words
The population of claim 15, prepared by the process further comprising maintaining a multiplicity of infection of at least one and a transductant-forming-unit to plaque-forming-unit ratio (tfu/pfu) of at least one.
Claim 23
Dependent Claim 18 words
The population of claim 15, prepared by the process wherein each recipient vector expresses a distinct genetic marker.
Claim 24
Dependent Claim 26 words
The population of claim 15, prepared by the process further comprising repeating steps (c) to (i) using additional cloned donor pools of mutant encoding nucleotide sequences.
Claim 25
Dependent Claim 17 words
The population of claim 15, prepared by the process wherein each phagemid expresses a distinct genetic marker.
Claim 26
Dependent Claim 17 words
The population of claim 15, prepared by the process wherein the helper phage is a filamentous phage.
Claim 27
Dependent Claim 15 words
The population of claim 24, prepared by the process wherein the filamentous phage is M13.
Claim 28
Dependent Claim 13 words
The population of claim 15, wherein the process further comprises screening intermediate populations.

References Cited (Backward Citations)

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