Characterisation of a solvent-tolerant haloarchaeal (R)-selective transaminase isolated from a Triassic period salt mine.
PMID 31123770 · Applied microbiology and biotechnology · 2019 · DOI 10.1007/s00253-019-09806-y
Authors: Stephen A Kelly; Damian J Magill; Julianne Megaw; Timofey Skvortsov; Thorsten Allers; John W McGrath; Christopher C R Allen; Thomas S Moody; Brendan F Gilmore
Abstract
Transaminase enzymes (TAms) are becoming increasingly valuable in the chemist's toolbox as a biocatalytic route to chiral amines. Despite high profile successes, the lack of (R)-selective TAms and robustness under harsh industrial conditions continue to prove problematic. Herein, we report the isolation of the first haloarchaeal TAm (BC61-TAm) to be characterised for the purposes of pharmaceutical biocatalysis. BC61-TAm is an (R)-selective enzyme, cloned from an extremely halophilic archaeon, isolated from a Triassic period salt mine. Produced using a Haloferax volcanii-based expression model, the resulting protein displays a classic halophilic activity profile, as well as thermotolerance (optimum 50 °C) and organic solvent tolerance. Molecular modelling predicts the putative active site residues of haloarchaeal TAms, with molecular dynamics simulations providing insights on the basis of BC61-TAm's organic solvent tolerance. These results represent an exciting advance in the study of transaminases from extremophiles, providing a possible scaffold for future discovery of biocatalytic enzymes with robust properties.
Amines; Archaea; Archaeal Proteins; Biocatalysis; Haloferax volcanii; Mining; Molecular Dynamics Simulation; Sodium Chloride; Solvents; Substrate Specificity; Thermotolerance; Transaminases
Cite
Stephen A Kelly; Damian J Magill; Julianne Megaw; Timofey Skvortsov; Thorsten Allers; John W McGrath; Christopher C R Allen; Thomas S Moody; Brendan F Gilmore. Characterisation of a solvent-tolerant haloarchaeal (R)-selective transaminase isolated from a Triassic period salt mine. Applied microbiology and biotechnology (2019). PMID 31123770. DOI 10.1007/s00253-019-09806-y.