A novel mechanism of protein thermostability : a unique N-terminal domain confers heat resistance to Fe/Mn-SODs

Superoxide dismutases (SODs), especially thermostable SODs, are widely applied in medical treatments, cosmetics, food, agriculture, and other industries given their excellent antioxidant properties. A novel thermostable cambialistic SOD from Geobacillus thermodenitrificans NG80-2 exhibits maximum activity at 70 °C and high thermostability over a broad range of temperatures (20-80 °C). Unlike other reported SODs, this enzyme contains an extra repeat-containing N-terminal domain (NTD) of 244 residues adjacent to the conserved functional SODA domain. Deletion of the NTD dramatically decreased its optimum active temperature (OAT) to 30 °C and also impaired its thermostability. Conversely, appending the NTD to a mesophilic counterpart from Bacillus subtilis led to a moderately thermophilic enzyme (OAT changed from 30 to 55 °C) with improved heat resistance. Temperature-dependant circular dichroism analysis revealed the enhanced conformational stability of SODs fused with this NTD. Furthermore, the NTD also contributes to the stress resistance of host proteins without altering their metal ion specificity or oligomerisation form except for a slight effect on their pH profile. We therefore demonstrate that the NTD confers outstanding thermostability to the host protein. To our knowledge, this is the first discovery of a peptide capable of remarkably improving protein thermostability and provides a novel strategy for bioengineering thermostable SODs.

Medienart:

E-Artikel

Erscheinungsjahr:

2014

Erschienen:

2014

Enthalten in:

Zur Gesamtaufnahme - volume:4

Enthalten in:

Scientific reports - 4(2014) vom: 02. Dez., Seite 7284

Sprache:

Englisch

Beteiligte Personen:

Wang, Wei [VerfasserIn]
Ma, Ting [VerfasserIn]
Zhang, Baoliang [VerfasserIn]
Yao, Nana [VerfasserIn]
Li, Mingchang [VerfasserIn]
Cui, Lianlei [VerfasserIn]
Li, Guoqiang [VerfasserIn]
Ma, Zhenping [VerfasserIn]
Cheng, Jiansong [VerfasserIn]

Links:

Volltext

Themen:

42Z2K6ZL8P
E1UOL152H7
EC 1.15.1.1
Iron
Journal Article
Manganese
Research Support, Non-U.S. Gov't
Superoxide Dismutase

Anmerkungen:

Date Completed 09.10.2015

Date Revised 13.11.2018

published: Electronic

Citation Status MEDLINE

doi:

10.1038/srep07284

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM244005575