Novel transferase and amylase, process for producing the enzymes, use thereof, and gene coding for the same

A novel transferase which acts on a maltooligosaccharide, all the glucose residues of the maltooligosaccharide being α-1,4-linked, so as to transfer the first α-1,4 linkage from the reducing end into an α-1,α-1 linkage.

A novel amylase which acts on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three sugar units from the reducing end are glucose residues, so as to liberate principally monosaccharides and/or disaccharides by hydrolyzing the substrate saccharide from the reducing end side.

A DNA fragment comprising a DNA sequence which codes for an amino acid sequence shown in Sequence No. 2 or an equivalent sequence thereof.

A DNA fragment comprising a DNA sequence which codes for an amino acid sequence shown in Sequence No. 4 or an equivalent sequence thereof.

A DNA fragment which hybridizes with the base sequence from the 335th base to the 2518th base of the base sequence shown in Sequence No. 1 or a complementary sequence thereof at 40° C. under an ionic strength of 5×SSC, and which codes for a novel transferase acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three glucose residues from the reducing end are α-1,4-linked, so as to transfer the first α-1,4 linkage from the reducing end into an α-1,α-1 linkage;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A DNA fragment which hybridizes with the base sequence from the 1880th base to the 2257th base of the base sequence shown in Sequence No. 1 or a complementary sequence thereof at 60° C. under an ionic strength of 6×SSPE, and which codes for a novel transferase acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three glucose residues from the reducing end are α-1,4-linked, so as to transfer the first α-1,4 linkage from the reducing end into an α-1,α-1 linkage;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A polypeptide comprising an amino acid sequence shown in Sequence No. 2 or an equivalent sequence thereof.

A polypeptide comprising an amino acid sequence shown in Sequence No. 4 or an equivalent sequence thereof.

A DNA fragment comprising a DNA sequence which codes for an amino acid sequence shown in Sequence No. 6 or an equivalent sequence thereof.

A DNA fragment comprising a DNA sequence which codes for an amino acid sequence shown in Sequence No. 8 or an equivalent sequence thereof.

A DNA fragment which hybridizes with the base sequence from the 639th or 642nd base to the 2315th base of the base sequence shown in Sequence No. 5 or a complementary sequence thereof at 40° C. under an ionic strength of 5×SSC, and which codes for a novel amylase having an activity of acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three sugar units from the reducing end are glucose residues, so as to liberate principally monosaccharides and/or disaccharides by hydrolyzing the substrate from the reducing end side;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A DNA fragment which hybridizes with the base sequence from the 639th or 642nd base to the 2315th base of the base sequence shown in Sequence No. 5 or a complementary sequence thereof at 40° C. under an ionic strength of 5×SSC, and which codes for a novel amylase having a principal activity of acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three sugar units from the reducing end side are glucose residues and the linkage between the first and second glucose residues from the reducing end side is α-1,α-1 while the linkage between the second and third glucose residues from the reducing end side is α-1,4, so as to liberate α,α-trehalose by hydrolyzing the α-1,4 linkage between the second and third glucose residues;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A DNA fragment which hybridizes with the base sequence from the 1393th base to the 2121th base of the base sequence shown in Sequence No. 7 or a complementary sequence thereof at 60° C. under an ionic strength of 6×SSPE, and which codes for a novel amylase having an activity of acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three sugar units from the reducing end are glucose residues, so as to liberate principally monosaccharides and/or disaccharides by hydrolyzing the substrate from the reducing end side;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A DNA fragment which hybridizes with the base sequence from the 1393th base to the 2121th base of the base sequence shown in Sequence No. 7 or a complementary sequence thereof at 40° C. under an ionic strength of 6×SSPE, and which codes for a novel amylase having a principal activity of acting on a substrate saccharide, the substrate saccharide being composed of at least three sugar units wherein at least three sugar units from the reducing end side are glucose residues and the linkage between the first and second glucose residues from the reducing end side is α-1,α-1 while the linkage between the second and third glucose residues from the reducing end side is α-1,4, so as to liberate α,α-trehalose by hydrolyzing the α-1,4 linkage between the second and third glucose residues;

• and a DNA fragment which codes for the amino acid sequence encoded by the foregoing DNA fragment.

A polypeptide comprising an amino acid sequence shown in Sequence No. 6 or an equivalent sequence thereof.

A polypeptide comprising an amino acid sequence shown in Sequence No. 8 or an equivalent sequence thereof.