An (R)-Selective Transaminase From Thermomyces stellatus: Stabilizing the Tetrameric Form

Heckmann, Christian M.; Gourlay, Louise J.; Dominguez, Beatriz; Paradisi, Francesca (2020). An (R)-Selective Transaminase From Thermomyces stellatus: Stabilizing the Tetrameric Form. Frontiers in Bioengineering and Biotechnology, 8(707) Frontiers Media 10.3389/fbioe.2020.00707

[img]
Preview
Text
fbioe-08-00707.pdf - Published Version
Available under License Creative Commons: Attribution (CC-BY).

Download (2MB) | Preview
[img]
Preview
Text
TsRTA_Frontiers_R1.pdf - Accepted Version
Available under License Creative Commons: Attribution (CC-BY).

Download (395kB) | Preview

The identification and 3D structural characterization of a homolog of the (R)-selective transaminase (RTA) from Aspergillus terreus (AtRTA), from the thermotolerant fungus Thermomyces stellatus (TsRTA) is here reported. The thermostability of TsRTA (40% retained activity after 7 days at 40°C) was initially attributed to its tetrameric form in solution, however subsequent studies of AtRTA revealed it also exists predominantly as a tetramer yet, at 40°C, it is inactivated within 48 h. The engineering of a cysteine residue to promote disulfide bond formation across the dimer-dimer interface stabilized both enzymes, with TsRTA_G205C retaining almost full activity after incubation at 50°C for 7 days. Thus, the role of this mutation was elucidated and the importance of stabilizing the tetramer for overall stability of RTAs is highlighted. TsRTA accepts the common amine donors (R)-methylbenzylamine, isopropylamine, and D-alanine as well as aromatic and aliphatic ketones and aldehydes.

Item Type:

Journal Article (Original Article)

Division/Institute:

08 Faculty of Science > Departement of Chemistry and Biochemistry

UniBE Contributor:

Paradisi, Francesca

Subjects:

500 Science > 570 Life sciences; biology
500 Science > 540 Chemistry

ISSN:

2296-4185

Publisher:

Frontiers Media

Language:

English

Submitter:

Francesca Paradisi

Date Deposited:

23 Jul 2020 09:51

Last Modified:

25 Jul 2020 07:52

Publisher DOI:

10.3389/fbioe.2020.00707

BORIS DOI:

10.7892/boris.145318

URI:

https://boris.unibe.ch/id/eprint/145318

Actions (login required)

Edit item Edit item
Provide Feedback