AP50 Polymerase Variants for Thermostable Rolling Circle Amplification
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Phi29 DNA polymerases have limitations such as limited thermostability, resulting in slower reaction kinetics and reduced amplification efficiency, especially at higher temperatures and with DNA having high G/C content, which restricts their utility in certain nucleic acid amplification methods like rolling circle amplification (RCA).
Innovation Solution
Recombinant Bacillus phage AP50 polymerases, including modified versions with amino acid deletions, insertions, or truncations, exhibit improved thermostability, processivity, and polymerization rate, enabling efficient nucleic acid amplification, particularly in rolling circle amplification (RCA), even at elevated temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If Phi29 DNA polymerase is used for rolling circle amplification, then nucleic acid amplification can be achieved, but thermostability is limited resulting in slower reaction kinetics and reduced amplification efficiency
Solution Approach 1:
The patent applies parameter changes by modifying the amino acid sequence of the Phi29 DNA polymerase to create variants with improved thermostability. Specific mutations in the polymerase structure allow it to maintain stability at higher temperatures, thereby improving reaction kinetics and amplification efficiency without sacrificing its core functionality in rolling circle amplification
2Adaptability or versatility
If Phi29 DNA polymerase is used for amplification, then nucleic acid amplification can be performed, but processivity is limited restricting utility in certain methods
Solution Approach 1:
The patent modifies the polymerase structure through amino acid substitutions to enhance processivity, allowing the enzyme to maintain longer continuous synthesis without dissociation from the template. This improved processivity expands the versatility of the polymerase for various amplification methods including rolling circle amplification and other isothermal amplification techniques
3Productivity
If Phi29 DNA polymerase is used for RCA, then amplification can occur, but at higher temperatures reaction kinetics slow down and amplification efficiency reduces
Solution Approach 1:
The patent employs parameter changes by introducing specific amino acid mutations that enhance the polymerase's thermal stability. These modifications allow the enzyme to maintain optimal conformation and catalytic activity at higher temperatures, thereby preserving fast reaction kinetics and high amplification efficiency even when conducted at elevated temperatures
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 recombinant AP50 polymerases provide enhanced thermostability and higher product yield, improving nucleic acid amplification efficiency and reducing reaction time, making them suitable for a wider range of nucleic acid amplification methods and samples, including in situ analysis.
Implementation Method 1
recombinant nucleic acid polymerases for DNA amplification reactions
Data Source
Figure 1
Figure 2A~2B
Figure 2C~2D
AI summary
The present disclosure relates in some aspects to recombinant Bacillus phage AP50 polymerases, modified AP50 polymerases, and compositions thereof. Also provided are methods of using the recombinant and/or modified AP50 polymerases for nucleic acid amplification (e.g., rolling circle amplification). In some aspects, the compositions and methods disclosed herein provide more robust amplification (e.g., RCA) reactions for improved in vitro and in situ analysis.