2results about How to "Keep it sweet" patented technology

The application discloses a mutant of single-chain sweet protein with high thermal stability and a gene of the mutant, wherein the mutant is obtained by mutating isoleucine (I) at the 5th position, glutamic acid (E) at the 23rd position, isoleucine (I) at the 26th position, tyrosine (Y) at the 65th position, glycine (G) at the 83rd position and asparagine (N) at the 90th position in the amino acid sequence shown in SEQ ID NO. 1 to alanine (A), arginine (R) and aspartic acid (D) respectively. m The Tm of the mutant of single-chain sweet protein with high thermal stability is increased by more than 19.4 DEG C, and the sweetness is maintained.

The application discloses a mutant of single-chain sweet protein with high thermal stability, a gene and engineering bacteria, wherein the mutant is a mutant of an amino acid sequence shown in SEQ ID NO. 1, and the isoleucine (I) at the 5th position is mutated into glutamic acid (E), the glutamic acid (E) at the 23rd position is mutated into alanine (A), the isoleucine (I) at the 26th position is mutated into arginine (R), the tyrosine (Y) at the 65th position is mutated into isoleucine (I), the glycine (G) at the 83rd position is mutated into glutamic acid (E) and the asparagine (N) at the 90th position is mutated into glutamic acid (E); the application is based on structural analysis and protein stability calculation aided design, and a mutant of single-chain sweet protein with high thermal stability is obtained by site-directed mutagenesis of the single-chain sweet protein; compared with the single-chain sweet protein, the mutant of single-chain sweet protein with high thermal stability has a T m which is increased by more than 18.4 DEG C and keeps the sweet taste.