Increasing thermal stability of glutamate decarboxylase from Escherichia. coli by site-directed saturation mutagenesis and its application in GABA production.


Abstract

Gamma-amino butyric acid (GABA) is an important bio-product used in pharmaceuticals, functional foods, and a precursor of the biodegradable plastic polyamide 4 (Nylon 4). Glutamate decarboxylase B (GadB) from Escherichia. coli is a highly active biocatalyst that can convert l-glutamate to GABA. However, its practical application is limited by the poor thermostability and only active under acidic conditions of GadB. In this study, we performed site-directed saturation mutagenesis of the N-terminal residues of GadB from Escherichia coli to improve its thermostability. A triple mutant (M6, Gln5Ile/Val6Asp/Thr7Gln) showed higher thermostability, with a 5.6 times (560%) increase in half-life value at 45 °C, 8.7 °C rise in melting temperature (Tm) and a 14.3 °C rise in the temperature at which 50% of the initial activity remained after 15 min incubation (T

Submission Details

ID: Bb3EiQLv

Submitter: Shu-Ching Ou

Submission Date: Dec. 28, 2018, 10:50 a.m.

Version: 1

Publication Details
Fan LQ;Li MW;Qiu YJ;Chen QM;Jiang SJ;Shang YJ;Zhao LM,J Biotechnol (2018) Increasing thermal stability of glutamate decarboxylase from Escherichia. coli by site-directed saturation mutagenesis and its application in GABA production. PMID:29660473
Additional Information

Structure view and single mutant data analysis

Study data

No weblogo for data of varying length.
Colors: D E R H K S T N Q A V I L M F Y W C G P
 

Data Distribution

Studies with similar sequences (approximate matches)

Correlation with other assays (exact sequence matches)


Relevant UniProtKB Entries

Percent Identity Matching Chains Protein Accession Entry Name
600.0 A,B,C,D,E,F Glutamate decarboxylase beta P69911 DCEB_ECO57
600.0 A,B,C,D,E,F Glutamate decarboxylase beta P69910 DCEB_ECOLI
600.0 A,B,C,D,E,F Glutamate decarboxylase beta P69912 DCEB_SHIFL
597.6 A,B,C,D,E,F Glutamate decarboxylase beta Q8FHG5 DCEB_ECOL6
593.4 A,B,C,D,E,F Glutamate decarboxylase beta P69909 DCEA_ECOL6
593.4 A,B,C,D,E,F Glutamate decarboxylase beta P69908 DCEA_ECOLI
592.2 A,B,C,D,E,F Glutamate decarboxylase beta P58228 DCEA_ECO57
592.2 A,B,C,D,E,F Glutamate decarboxylase beta Q83PR1 DCEA_SHIFL