Modified PH129 Polymerase for Faster Genome Amplification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing DNA polymerases, such as phi29, face challenges in improving processivity and strand displacing activity without compromising accuracy and stability, limiting their effectiveness in amplifying whole genomes with minimal bias.
Innovation Solution
Development of modified polymerases with specific amino acid substitutions, such as K135E, L216P, and K536E, to enhance nucleotide incorporation rates and processivity, facilitating faster amplification.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If amino acid substitutions are introduced to improve processivity and strand displacing activity, then nucleotide incorporation rate and amplification speed increase, but accuracy and stability may be compromised
Solution Approach 1:
The patent applies parameter changes by systematically modifying specific amino acid residues at defined positions (e.g., positions 216, 394, 417, 536, 578) to optimize enzyme kinetics. Multiple variant sequences are generated with substitutions such as P216, V394, N417, E536, and G578 to enhance nucleotide incorporation rate while maintaining fidelity through controlled parameter variation in the protein structure
Solution Approach 2:
The patent implements local quality by introducing site-specific amino acid substitutions at critical positions within the polymerase structure rather than global modifications. Specific residues at positions 216, 394, 417, 536, and 578 are targeted for substitution with particular amino acids (proline, valine, asparagine, glutamic acid, glycine) to locally enhance processivity and strand displacing activity while preserving overall enzyme accuracy and stability
2Productivity
If amino acid substitutions are introduced to enhance strand displacing activity, then amplification efficiency improves, but enzyme stability may deteriorate
Solution Approach 1:
The patent applies parameter changes by systematically modifying specific amino acid residues at defined positions (e.g., positions 216, 394, 417, 536, 578) to optimize enzyme kinetics. Multiple variant sequences are generated with substitutions such as P216, V394, N417, E536, and G578 to enhance nucleotide incorporation rate while maintaining fidelity through controlled parameter variation in the protein structure
Solution Approach 2:
The patent employs beforehand cushioning by designing polymerase variants with multiple stabilizing amino acid substitutions that preemptively compensate for potential stability losses. The combination of substitutions at positions 216, 394, 417, 536, and 578 creates a buffered system that maintains enzyme stability even as strand displacing activity is enhanced, preventing deterioration before it occurs
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 modified polymerases exhibit superior nucleotide processivity and faster amplification kinetics compared to wild-type phi29 DNA polymerase, enabling more efficient genome amplification.
Implementation Method 1
DNA polymerases add nucleotide triphosphate (dNTP) residues to the 3′-end of the growing DNA chain... the modified polymerases exhibit superior nucleotide processivity and faster amplification kinetics
Implementation Method 2
phi29 contains an exonuclease domain that catalyzes 3′→5′ exonucleolysis of mismatched nucleotides preferentially on single-stranded DNA or RNA, thereby enhancing replication fidelity at least 100-fold
Data Source
AI summary
Disclosed herein, inter alia, are mutant enzymes, kits, and methods of use thereof.