Mutated Arylsulfotransferases for PAP-to-PAPS Conversion
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The high cost and instability of 3′-phosphoadenosine-5′-phosphosulfate (PAPS) as a cofactor in sulfotransferase reactions hinder large-scale production of sulfated products like heparan sulfate and heparin, necessitating improved enzyme catalytic activity and cost-effective conversion methods.
Innovation Solution
Mutated arylsulfotransferases with specific amino acid substitutions enhance the conversion of 3′,5′-adenosine-phosphate (PAP) to PAPS, offering enhanced catalytic activity and thermal stability, enabling efficient and cost-effective sulfation processes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If wild-type sulfotransferases are used for sulfation reactions, then the reaction can proceed with natural cofactors, but the catalytic activity is insufficient and PAPS is expensive and unstable
Solution Approach 1:
The patent applies parameter changes by mutating specific amino acid residues in the sulfotransferase enzyme structure. The mutations at positions 138 and 236 (among others) alter the enzyme's catalytic properties, enhancing its activity toward PAPS while improving the overall stability and efficiency of the sulfation reaction system
Solution Approach 2:
The patent creates mutant versions of the sulfotransferase enzyme that replicate and enhance the natural enzyme's function. These mutant enzymes copy the core catalytic mechanism while improving performance metrics such as catalytic activity and cofactor efficiency, providing a more reliable and productive system
2Productivity
If wild-type arylsulfotransferase is used to convert PAP to PAPS, then the process is simple, but the conversion efficiency is low
Solution Approach 1:
The patent enhances conversion efficiency by introducing specific amino acid substitutions in the arylsulfotransferase enzyme. These parameter changes at key positions (138, 236, and others) optimize the enzyme's catalytic mechanism for PAP to PAPS conversion, achieving higher productivity despite increased structural complexity
Solution Approach 2:
The patent uses mutant arylsulfotransferase enzymes that can efficiently convert inexpensive PAP to PAPS in a single-use or limited-use manner. The mutant enzymes provide high conversion efficiency in straightforward reactions, making the process economically viable without requiring complex enzyme recycling systems
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 mutated arylsulfotransferases provide a low-cost, high-yield source of PAPS, facilitating large-scale synthesis of sulfated substrates such as heparan sulfate and heparin, with improved catalytic activity and stability.
Implementation Method 1
Sulfotransferases (SULTS) are a family of enzymes that transfer the sulfate group from PAPS onto usually a hydroxyl group of a target substrate
Implementation Method 2
The sulfation reaction needs a sulfotransferase (SULT) enzyme as a catalyst
Data Source
AI summary
The invention relates to non-naturally occurring mutated arylsulfotransferases comprising (i) an amino acid substitution in at least one amino acid position selected among positions 6, 7, 8, 9, 11, 17, 20, 33, 62, 97, 138, 195, 236, 239, 244, 263, and combinations thereof, wherein the position is relative to the amino acids sequence of rat arylsulfotransferase IV SEQ ID NO: 1 and (ii) an amino acid sequence having at least 60% sequence identity with amino acids sequence SEQ ID NO: 1. The mutated arylsulfotransferase may have a sulfotransferase activity for converting adenosine 3′,5′-bisphosphate (PAP) into 3′-phosphoadenosine-5′-phosphosulfate (PAPS) enhanced compared to the wild-type enzyme.