Abstract: The present disclosure relates to methods, processes and systems for enzymatic synthesis of oligonucleotide from a single-stranded, immobilized primer in the presence of a polymerase. Using the disclosed methods single-stranded oligonucleotides can be synthesized enzymatically from a single-stranded, immobilized primer in the presence of deoxyribonucleotide triphosphates or ribonucleotide triphosphates. Dideoxyribonucleotide triphosphates, deoxyribonucleotide triphosphates with reversible terminators, or ribonucleotide triphosphates with reversible terminators can be added enzymatically to the end of the primer or its extension products. According to the disclosed method, a single-stranded primer can bind to a template such that the thus-formed double-stranded structure can allow the polymerase to extend the primer at 3? end.

Abstract: The present disclosure provides methods of sequencing polynucleotides and compounds, compositions useful for sequencing of polynucleotides. The chemical compounds include nucleotides and their analogs which possess a sugar moiety comprising a cleavable chemical group capping the 3?-OH group and a base that is attached to a label through a cleavable linker comprising a disulfide bond. In addition, both the disulfide bond and the cleavable chemical group are cleavable by a chemical reagent. Furthermore, after the disulfide bond is cleaved by the chemical reagent, there is no free thiol group linked to the base of the nucleotides according to the fragmentation reaction shown below as an example. Example compounds according to the present disclosure are shown as Formula (I): wherein w is 1-5; X is O, S, or BH3; B is a nucleotide base or an analog thereof, L1-3 are linkers; and D1 is a label.

Abstract: The present disclosure relates to methods, processes and systems for enzymatic synthesis of oligonucleotide from a single-stranded, immobilized primer in the presence of a polymerase. Using the disclosed methods single-stranded oligonucleotides can be synthesized enzymatically from a single-stranded, immobilized primer in the presence of deoxyribonucleotide triphosphates or ribonucleotide triphosphates. Dideoxyribonucleotide triphosphates, deoxyribonucleotide triphosphates with reversible terminators, or ribonucleotide triphosphates with reversible terminators can be added enzymatically to the end of the primer or its extension products. According to the disclosed method, a single-stranded primer can bind to a template such that the thus-formed double-stranded structure can allow the polymerase to extend the primer at 3? end.

Abstract: The present disclosure provides methods of sequencing polynucleotides and compounds, compositions useful for sequencing of polynucleotides. The chemical compounds include nucleotides and their analogs which possess a sugar moiety comprising a cleavable chemical group capping the 3?-OH group and a base that is attached to a detectable label through a cleavable linker comprising a disulfide bond. In addition, both the disulfide bond and the cleavable chemical group are cleavable by a chemical reagent. Furthermore, after the disulfide bond is cleaved by the chemical reagent, there is no free thiol group linked to the base of the nucleotides.