Role of C-terminal domain in a manganese-catalase from Geobacillus thermopakistaniensis.
J Biosci Bioeng
; 134(3): 203-212, 2022 Sep.
Article
en En
| MEDLINE
| ID: mdl-35811183
Catalases catalyze the decomposition of hydrogen peroxide into water and oxygen. We have characterized two manganese-catalases from Geobacillus thermopakistaniensis, CatGt and Cat-IIGt, which exhibited significant variation in their sequence, structure and properties. There was only 23% sequence identity between the two. The striking structural difference was the presence of an extended C-terminal domain in CatGt. Molecular modelling and docking studies revealed that deletion of the C-terminal domain removes non-specific binding, which results in increased substrate affinity. To verify experimentally, a C-terminal truncated version of CatGt, named as CatGt-ΔC, was produced in Escherichia coli and effects of deletion were analyzed. There was no significant difference in optimal pH, optimal temperature and substrate specificity of CatGt and CatGt-ΔC. However, Km value was reduced from 259 to 157 mM and CatGt-ΔC exhibited â¼1.5-fold higher catalytic efficiency as compared to CatGt. Furthermore, removal of the C-terminal domain converted the tetrameric nature to monomeric, and reduced the thermostability of the truncated protein. These results demonstrate that C-terminal domain of CatGt might have little role in maintaining enzyme function but provides additional structural stability to the protein, which is a desired property for industrial applications.
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Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Geobacillus
Idioma:
En
Revista:
J Biosci Bioeng
Asunto de la revista:
ENGENHARIA BIOMEDICA
/
MICROBIOLOGIA
Año:
2022
Tipo del documento:
Article
País de afiliación:
Pakistán
Pais de publicación:
Japón