Methods and apparatus for single molecule sequencing using energy transfer detection
Provided herein are systems and methods for nucleotide incorporation reactions. The systems comprise polymerases having altered nucleotide incorporation kinetics and are linked to an energy transfer donor moiety, and nucleotide molecules linked with at least one energy transfer acceptor moiety. The donor and acceptor moieties undergo energy transfer when the polymerase and nucleotide are proximal to each other during nucleotide binding and/or nucleotide incorporation. As the donor and acceptor moieties undergo energy transfer, they generate an energy transfer signal which can be associated with nucleotide binding or incorporation. Detecting a time sequence of the generated signals, or the change in the signals, can be used to determine the order of the incorporated nucleotides, and can therefore be used to deduce the sequence of the target molecule.
1. A composition, comprising: (i) a modified polymerase linked to an energy transfer donor moiety, (ii) a nucleic acid template molecule, (iii) a nucleic acid primer molecule, and (iv) at least one type of nucleotide having an energy transfer acceptor moiety, wherein the modified polymerase comprises the amino acid sequence of SEQ ID NO: 2.
2. The composition of claim 1 , wherein the nucleic acid template molecule or the nucleic acid primer molecule is immobilized to a surface.
3. The composition of claim 1 , wherein the energy transfer donor moiety is a nanoparticle or a fluorescent dye.
4. The composition of claim 3 , wherein the nanoparticle is an inorganic fluorescent nanoparticle.
5. The composition of claim 3 , wherein the nanoparticle is 1-20 nm in its largest dimension.
6. The composition of claim 3 , wherein the nanoparticle is a non-blinking nanoparticle.
7. The composition of claim 1 , wherein the at least one type of nucleotide comprises 3-10 phosphate groups.
8. The composition of claim 7 , wherein a terminal phosphate group of the at least one type of nucleotide is linked to the acceptor moiety.
9. The composition of claim 1 , wherein the at least one type of nucleotide is selected from a group consisting of adenosine, guanosine, cytosine, thymidine and uridine.
10. The composition of claim 9 , wherein each of the at least one type of nucleotide is linked to a different type of energy transfer acceptor moiety.
11. The composition of claim 1 , wherein the energy transfer acceptor moiety is a fluorescent dye.
12. The composition of claim 1 , wherein the nucleic acid molecule is DNA or RNA.