Modified nucleotide reagents
Labeled nucleotide analogs comprising at least one avidin protein, at least one dye-labeled compound, and at least one nucleotide compound are provided. The analogs are useful in various fluorescence-based analytical methods, including the analysis of highly multiplexed optical reactions in large numbers at high densities, such as single molecule real time nucleic acid sequencing reactions. The analogs are detectable with high sensitivity at desirable wavelengths. They contain structural components that modulate the interactions of the analogs with DNA polymerase, thus decreasing photodamage and improving the kinetic and other properties of the analogs in sequencing reactions. Also provided are nucleotide and dye-labeled compounds of the subject analogs, as well as intermediates useful in the preparation of the compounds and analogs. Compositions comprising the compounds, methods of synthesis of the intermediates, compounds, and analogs, and mutant DNA polymerases are also provided.
1. A nucleotide compound of structural formula (I):
wherein
L is a nucleotide linker element comprising at least one affinity modulating element; wherein the at least one affinity modulating element is an aromatic spacer element;
P is a polyphosphate element;
Nu is a nucleoside element;
X is a multivalent central core element;
B″ is a terminal coupling element;
n is an integer from 1 to 4; and
o is 0 or 1.
2. The nucleotide compound of claim 1 , wherein the at least one affinity modulating element decreases the K m of a nucleotide-dependent enzyme for the nucleotide compound or increases the enzymatic rate of the nucleotide-dependent enzyme.
3. The nucleotide compound of claim 1 , wherein the aromatic spacer element is a substituted or unsubstituted monocyclic, bicyclic, tricyclic, or tetracyclic aromatic moiety.
4. The nucleotide compound of claim 3 , wherein the aromatic spacer element optionally comprises at least one anionic substituent.
5. The nucleotide compound of claim 4 , wherein the aromatic spacer element optionally comprises at least two anionic substituents.
6. The nucleotide compound of claim 4 , wherein the optional at least one anionic substituent is —SO 3 H.
7. The nucleotide compound of claim 3 , wherein the aromatic spacer element is represented by structural formula (II):
wherein
the A-ring and the B-ring is each independently a 5-7 atom cyclic structure, wherein at least one of the A-ring or the B-ring is aromatic; and
the A-ring or the B-ring optionally comprises at least one anionic substituent.
8. The nucleotide compound of claim 7 , wherein the optional at least one anionic substituent is —SO 3 H.
9. The nucleotide compound of claim 3 , wherein the aromatic spacer element is represented by one of the following structural formulae:
wherein
one of the A 1 , A 2 , A 3 , and A 4 groups is
and the other groups are —CH 2 — or a bond; and
R 1 , R 2 , R 3 , R 4 , R 5 , and R 6 are independently H or an anionic substituent.
10. The nucleotide compound of claim 9 , wherein the anionic substituent is —SO 3 H.
11. The nucleotide compound of claim 9 , wherein the aromatic spacer element is represented by structural formula (IIC) or (IIC′):
12. The nucleotide compound of claim 9 , wherein the aromatic spacer element is represented by one of the following structural formulae:
13. The nucleotide compound of claim 1 , wherein L further comprises an alkyl linker group, optionally comprising an amide bond.
14. The nucleotide compound of claim 1 , wherein L further comprises a triazole.
15. The nucleotide compound of claim 1 , wherein B″ comprises a biotin moiety.
16. The nucleotide compound of claim 15 , wherein B″ comprises a bis-biotin moiety.
17. The nucleotide compound of claim 1 , wherein o is 1.
18. The nucleotide compound of claim 17 , wherein n is 2.
19. The nucleotide compound of claim 17 , wherein X comprises a polyamine moiety.
20. The nucleotide compound of claim 1 , wherein o is 0 and n is 1.
21. The nucleotide compound of claim 1 , wherein the compound does not contain a dye.
22. The nucleotide compound of claim 1 , wherein L further comprises a shield element.
23. A nucleotide reagent composition comprising an avidin protein and the nucleotide compound of claim 1 .
24. The nucleotide compound of claim 1 , wherein at least one B″ comprises a reactive functional group.
25. The nucleotide compound of claim 24 , wherein at least one B″ comprises a residue derived from a reactive functional group.
26. The nucleotide compound of claim 25 , wherein the residue derived from a reactive functional group is an amide moiety.
27. The nucleotide compound of claim 25 , wherein the residue derived from a reactive functional group results from a click reaction.