Disclosed are devices, systems and methods for direct measurement of polymerase activity. In one example, a device includes at least a first electrode and a second electrode, the first and second electrode being separated by a gap; and a polymerase with two attachment sites, one for attaching to the first electrode and a second for attaching to the second electrode, wherein the two attachment sites are separated by a distance of at least about 1 nm and the distance does not significantly change with conformational changes of the polymerase.

Provided herein relates to DNA polymerase variants and kits including the same, where the DNA polymerase variant has an improved function and activity of performing template-independent nucleic acids synthesis using canonical nucleotides and non-canonical nucleotide analogues in a thermotolerant manner.

This disclosure relates to thermophilic family B DNA polymerases comprising a neutral amino acid residue at a certain position near the C-terminus of the catalytic domain, which corresponds to a position occupied by a basic amino acid residue in wild-type Pfu polymerase. The thermophilic family B DNA polymerases provided herein also comprise an N-terminal domain comprising a uracil-binding pocket that has been modified to reduce template uracil binding. Related uses, methods, and compositions are also provided. In some embodiments, the polymerases comprise a 3′-5′ exonuclease domain and/or a sequence non-specific dsDNA binding domain.

The present disclosure provides a fusion polypeptide comprising: a) an enzymatically active RNA-guided endonuclease that introduces a single-stranded break in a target DNA; and b) an error-prone DNA polymerase. The present disclosure provides a system comprising: a) a fusion polypeptide of the present disclosure; and b) a guide RNA. The present disclosure provides a cell comprising a fusion polypeptide of the present disclosure, or a system of the present disclosure. The present disclosure provides a method of mutagenizing a target polynucleotide.

Amino acid substitutions that provide for increased elongation rates, resistance to PCR inhibitors, and reverse transcriptase activity of Thermus aquaticus (Taq) DNA polymerase enzymes are provided. Also provided are related methods of using the Taq DNA polymerase enzymes to rapidly detect nucleic acids of interest in crude biological samples, without DNA/RNA extraction.

Disclosed are Taq DNA polymerase mutants which exhibit enhanced efficiency in qPCR compared to the wild type Taq DNA polymerase. Such mutants include: V62S, V64S, A70F, F73A, A77F, P253G, E255K, D257R, A259F, A271F, L288S, E289K, S357I, L361S, L376S, P382G, T385I, G418P, R419D, E421K, L461S, A472F, E497K, L498S, E524K, D551R, R556D, S679I, L789S, E189K/E507K/E742K (See Sequence Listing Guide for the mutants' amino acid and protein sequences).

The invention relates to the use of a polysaccharide having at least four saccharide units, such as stachyose, as a glass-forming agent for the freeze-drying of a reaction mixture comprising an enzyme. In particular, the enzyme is a polymerase useful in a nucleic acid amplification reaction such as a Polymerase Chain Reaction. Compositions comprising such polysaccharides as well as methods for preparing them, kits containing them and methods for using them form further aspects of the invention.

The invention relates to a method of reacting one or more L-nucleotides with a first L-nucleic acid in the presence of a D-enzyme that adds the one or more L-nucleotides to the 3′ end of the first L-nucleic acid.

Disclosed herein, inter alia, are methods, enzymes, and compositions useful for nucleic acid sequencing.

Provided herein are compositions and systems for use in polymerase-dependent, nucleotide transient-binding methods. The methods are useful for deducing the sequence of a template nucleic acid molecule and single nucleotide polymorphism (SNP) analyses. The methods rely on the fact that the polymerase transient-binding time for a complementary nucleotide is longer compared to that of a non-complementary nucleotide. The labeled nucleotides transiently-binds the polymerase in a template-dependent manner, but does not incorporate. The methods are conducted under any reaction condition that permits transient binding of a complementary or non-complementary nucleotide to a polymerase, and inhibits nucleotide incorporation.