Method for sequencing using branching fraction of incorporatable nucleotides

摘要

Provided are methods for enhanced sequencing of nucleic acid templates. Also provided are reaction conditions that increase branching fractions during polymerization reactions. Also provided are compositions comprising modified recombinant polymerases that exhibit branching fractions that are higher than the branching fractions of the polymerases from which they were derived. Provided are compositions comprising modified recombinant polymerases that exhibit delayed translocation relative to the polymerases from which they were derived. Also provided are compositions comprising modified recombinant polymerases that exhibit increased nucleotide or nucleotide analog residence time at an active site of the polymerase. Provided are methods for generating polymerases with the aforementioned phenotypes and methods of using such polymerases to sequence a DNA template or make a DNA. Also provided are methods and nucleic acid sequencing systems for determining which labeled nucleotide is incorporated at a site during a template-dependent polymerization reaction.