Abstract: The present invention relates to a polymerase enzyme with improved ability to incorporate reversibly terminating nucleotides. The enzyme comprising the following mutations in the motif A region (SGS). It relates to a polymerase enzyme according to SEQ ID NO. 1 or any polymerase that shares at least 70% amino acid sequence identity thereto, comprising a mutation selected from the group of (i) at position 412 of SEQ ID NO. 1: serine (S) (L412S) and/or, (ii) at position 413 of SEQ ID NO. 1: glycine (G) (Y413G) and/or (iii) at position 414 of SEQ ID NO. 1: serine (S) (P414S), wherein the enzyme has little or no 3?-5? exonuclease activity.

Abstract: The present invention relates to a polymerase enzyme with improved ability to incorporate reversibly terminating nucleotides. The enzyme comprising the following mutations in the motif A region (SGS). It relates to a polymerase enzyme according to SEQ ID NO. 1 or any polymerase that shares at least 70% amino acid sequence identity thereto, comprising a mutation selected from the group of (i) at position 412 of SEQ ID NO. 1: serine (S) (L412S) and/or, (ii) at position 413 of SEQ ID NO. 1: glycine (G) (Y413G) and/or (iii) at position 414 of SEQ ID NO. 1: serine (S) (P414S), wherein the enzyme has little or no 3?-5? exonuclease activity.

Abstract: The present invention relates to a family B polymerase enzyme comprising the following mutations, a mutation in the motif A region, wherein a threonine is the second amino acid of the motif A region, wherein the motif A region is homologous to amino acids 408 to 410 in 9° N, a mutation leading to a reduction or elimination of the 3?-5? exonuclease activity if present in said family B polymerase, wherein said polymerase additionally comprises one or both of the following mutations in the motif A region, L408Y or L408F and/or P410S or P410G. It may be used in DNA sequencing and may be present in a kit.

Abstract: The present invention relates to a family B polymerase enzyme comprising the following mutations, a mutation in the motif A region, wherein a threonine is the second amino acid of the motif A region, wherein the motif A region is homologous to amino acids 408 to 410 in 9° N, a mutation leading to a reduction or elimination of the 3?-5? exonuclease activity if present in said family B polymerase, wherein said polymerase additionally comprises one or both of the following mutations in the motif A region, L408Y or L408F and/or P410S or P410G. It may be used in DNA sequencing and may be present in a kit.