L-Tyrosine Exporter Variant for Amino Acid Specificity Shift

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

There is no reported protein in microorganisms, particularly in the genus Corynebacterium, that specifically exports L-tyrosine or aromatic amino acids, limiting the efficiency of L-tyrosine production.

Innovation Solution

A protein variant is developed by substituting the 79th amino acid from the N-terminus of the amino acid sequence of SEQ ID NO: 52 with alanine or glycine, and a polynucleotide encoding this variant is used to enhance L-tyrosine export in microorganisms.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Productivity

If no specific L-tyrosine exporting protein is used, then the microorganism can maintain its native state, but L-tyrosine production efficiency is limited

Engineering Contradiction:

ImproveL-tyrosine production efficiencyVSAvoidamino acid export specificity

Core Design Contradiction:

ProductivityVSAdaptability or versatility

Solution Approach 1:

The patent applies parameter changes by substituting the 79th amino acid in the exporting protein sequence with alanine or glycine. This specific amino acid substitution modifies the protein's substrate specificity, enabling it to export L-tyrosine efficiently while maintaining its function as an amino acid exporter. The parameter change at the molecular level directly resolves the contradiction between maintaining native state and improving production efficiency.

Inventive Principle:

Principle #35Parameter changes

2Adaptability or versatility

If existing amino acid exporting proteins (like yddG) are used, then export function is provided, but specificity to L-tyrosine is insufficient as they show higher specificity to L-phenylalanine

Engineering Contradiction:

Improveamino acid export specificityVSAvoidL-tyrosine export efficiency

Core Design Contradiction:

Adaptability or versatilityVSProductivity

Solution Approach 1:

The patent applies local quality by making a specific modification at the 79th position of the exporting protein. This localized amino acid substitution (to alanine or glycine) changes the protein's substrate preference from L-phenylalanine to L-tyrosine. The local change in amino acid composition at a specific position creates the desired specificity without altering the overall protein structure or function, thereby resolving the contradiction between export function and substrate specificity.

Inventive Principle:

Principle #3Local quality

Data Source

PatentUS12545939B2L-tyrosine-exporting protein variant and method for producing l-tyrosine using the same

Publication Date: 2026.02.10 CJ CHEILJEDANG CORP

AI summary

A protein variant having an L-tyrosine exporting activity, a microorganism expressing the same, and use thereof.