Trypsin Variants for Orthogonal Polypeptide Dual-Modification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for site-specific modification of polypeptides are limited in achieving orthogonal dual-modification using enzymes of the same origin without significant cross-reactivity and often require metal ions, which can restrict their application.
Innovation Solution
Development of trypsin variants with specific amino acid substitutions that enhance affinity for nucleophilic substrates and reduce hydrolysis activity, allowing for orthogonal dual-modification using two different trypsin enzymes on distinct recognition sequences without metal ion dependence.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If trypsin variants are used for site-specific modification of polypeptides, then modification specificity is improved, but cross-reactivity between enzymes of the same origin occurs
Solution Approach 1:
The patent divides the enzyme family into distinct functional segments by creating variants with different recognition sequences (e.g., YRAH vs YRKH). Each variant is optimized for a specific substrate type, allowing parallel processing without cross-interference. This segmentation enables orthogonal dual-modification where each enzyme acts independently on its designated target.
Solution Approach 2:
The patent applies local quality by introducing specific amino acid substitutions at defined positions (e.g., position 60, 189, 39, or 59) to create localized functional differences. These point mutations confer specific substrate preferences to individual enzymes while maintaining overall family homology, thereby achieving specificity without sacrificing reliability.
2Productivity
If metal ions are used to enhance enzyme activity, then catalytic efficiency is improved, but application versatility is reduced due to metal ion dependence
Solution Approach 1:
The patent extracts and eliminates the metal ion requirement from the enzyme system. By optimizing the active site through amino acid substitutions, the variants achieve high catalytic efficiency through purely enzymatic mechanisms, removing the constraint of metal ion availability and expanding application versatility to systems where metal ions are absent or problematic.
3Power
If hydrolysis activity is high in trypsin variants, then enzyme reactivity is improved, but synthetic properties are worsened due to unwanted peptide cleavage
Solution Approach 1:
The patent inverts the typical trypsin function by reducing hydrolysis activity while enhancing aminolysis activity. Through specific mutations, the enzyme is transformed from a primarily degradative enzyme to a synthetic enzyme that favors bond formation over cleavage, enabling peptide synthesis rather than just degradation.
Solution Approach 2:
The patent changes the kinetic parameters of the enzyme by introducing amino acid substitutions that alter the energy landscape of the reaction. These mutations modify the transition state stabilization and substrate binding to shift the reaction pathway from hydrolysis-dominated to aminolysis-dominated, improving synthetic properties while maintaining reactivity.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The trypsin variants demonstrate improved synthetic properties, favoring aminolysis over hydrolysis and enabling efficient, metal-ion-independent orthogonal dual-modification of polypeptides, enhancing the precision and versatility of peptide modification processes.
Implementation Method 1
Ser195 forms an acyl enzyme intermediate with the substrate to be cleaved and is thus significantly involved in the protease reactivity. This acyl enzyme intermediate can be attacked by variable nucleophiles such as water (peptide hydrolysis), amines (peptide aminolysis), alcohols and thiols (peptide (thio)esterification).
Implementation Method 2
The C-terminal modification of polypeptides via stable amide bonds is based on transamidation. The C-terminal end region of the polypeptide to be labeled forms the acyl enzyme intermediate with the trypsin variant, which can then be attacked nucleophilically by the labeled acyl acceptor.
Implementation Method 3
Enzymatic methods for modifying polypeptides use intrinsic properties of enzymes such as the recognition of certain amino acid sequences or functionalities after the introduction of the corresponding recognition sequences by means of site-directed mutagenesis. Regiospecificity is generated by the high substrate specificity of the respective enzymes.
Data Source
AI summary
The present invention relates to trypsin variants with improved enzymatic properties, and particularly relates to a mutated trypsin comprising an amino acid substitution at least at two amino acid positions leading to an increased affinity for the nucleophilic substrate and/or at least at two amino acid positions leading to a reduced hydrolysis activity.