Premium
The Peculiar Case of the Hyper‐thermostable Pyrimidine Nucleoside Phosphorylase from Thermus thermophilus **
Author(s) -
Kaspar Felix,
Neubauer Peter,
Kurreck Anke
Publication year - 2021
Publication title -
chembiochem
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 126
eISSN - 1439-7633
pISSN - 1439-4227
DOI - 10.1002/cbic.202000679
Subject(s) - thermus thermophilus , pyrimidine , nucleoside , chemistry , nucleobase , purine nucleoside phosphorylase , biocatalysis , nucleotide , thermus aquaticus , combinatorial chemistry , thermus , enzyme , stereochemistry , catalysis , organic chemistry , biochemistry , thermophile , reaction mechanism , dna , escherichia coli , purine , gene
The poor solubility of many nucleosides and nucleobases in aqueous solution demands harsh reaction conditions (base, heat, cosolvent) in nucleoside phosphorylase‐catalyzed processes to facilitate substrate loading beyond the low millimolar range. This, in turn, requires enzymes that can withstand these conditions. Herein, we report that the pyrimidine nucleoside phosphorylase from Thermus thermophilus is active over an exceptionally broad pH (4–10), temperature (up to 100 °C) and cosolvent space (up to 80 % ( v / v ) nonaqueous medium), and displays tremendous stability under harsh reaction conditions with predicted total turnover numbers of more than 10 6 for various pyrimidine nucleosides. However, its use as a biocatalyst for preparative applications is critically limited due to its inhibition by nucleobases at low concentrations, which is unprecedented among nonspecific pyrimidine nucleoside phosphorylases.