Surface comprising DNA polymerase having mutations bound through an affinity tag
Active surface coupled polymerases, surfaces that include such polymerases, and methods of making and using surface-attached polymerases are provided.
1. A surface comprising an immobilized active DNA polymerase bound thereon, wherein the polymerase comprises at least 95% sequence identity over a region of at least 150 residues to the wild-type Φ29 DNA polymerase of SEQ ID NO: 1, wherein the polymerase comprises mutations at sites corresponding to E375 and K512 relative to the wild-type Φ29 DNA polymerase of SEQ ID NO: 1, wherein the polymerase is bound to the surface through an affinity tag, and wherein the polymerase displays a k cat /K m that is at least 25% as high as a corresponding DNA polymerase in solution.
2. The surface of claim 1 , wherein a location of the polymerase on the surface provides a spatial address of the polymerase on the surface.
3. The surface of claim 1 , wherein the surface comprises a polymer, a ceramic, glass, a bead, a microbead, a polymer bead, a glass bead, a well, a microwell, a slide, a grid, a rotor, a microchannel, or a combination thereof.
4. The surface of claim 1 , wherein the surface is a planar surface.
5. The surface of claim 1 , wherein the surface comprises a zero mode waveguide.
6. The surface of claim 1 , wherein the polymerase displays a k cat /K m that is at least 50% as high as a corresponding DNA polymerase in solution.
7. The surface of claim 1 , wherein the polymerase displays a k cat /K m that is at least 75% as high as a corresponding DNA polymerase in solution.
8. The surface of claim 1 , wherein two or more surface coupling domains couple the polymerase to the surface.
9. The surface of claim 1 , wherein the polymerase is coupled to the surface through a surface coupling domain that is at least 5 kDa in size.
10. The surface of claim 1 , wherein the polymerase is coupled to the surface through a surface coupling domain that is at least 10 kDa in size.
11. The surface of claim 1 , wherein the polymerase is coupled to the surface through a surface coupling domain that is at least 50 kDa in size.
12. The surface of claim 1 , wherein the polymerase is coupled to the surface through a surface coupling domain that is at least 100 kDa in size.
13. The surface of claim 1 , wherein the affinity tag is located in the N-terminal region of the polymerase.
14. The surface of claim 1 , wherein the polymerase comprises a mutation selected from: a histidine substitution at position E375, a serine substitution at position E375, a lysine substitution at position E375, an arginine substitution at position E375, an alanine substitution at position E375, a glutamine substitution at position E375, a tryptophan substitution at position E375, a tyrosine substitution at position E375, a phenylalanine substitution at position E375, an alanine substitution at position K512, a tyrosine substitution at position K512, a tryptophan substitution at position K512, a phenylalanine substitution at position K512, a leucine substitution at position K512, a histidine substitution at position K512, an aspartate substitution at position K512, a glutamate substitution at position K512, and combinations thereof, wherein amino acid positions are numbered relative to the wild-type Φ29 DNA polymerase of SEQ ID NO: 1.
15. The surface of claim 1 , wherein the polymerase comprises tyrosine residues at sites corresponding to E375 and K512 relative to the wild-type Φ29 DNA polymerase of SEQ ID NO: 1.