Point mutation Arg153-His at surface of Bacillus lipase contributing towards increased thermostability and ester synthesis: insight into molecular network.
Mol Cell Biochem
; 443(1-2): 159-168, 2018 Jun.
Article
em En
| MEDLINE
| ID: mdl-29086164
ABSTRACT
In order to design proteins with improved properties i.e. thermostability, catalytic efficiency and to understand the mechanisms underlying, a thermostable variant of Bacillus lipase was generated by site-directed mutagenesis with enhanced thermal (∆Tm = + 12 °C) and chemical (∆Cm denaturation for Gdmcl = + 1.75 M) stability as compared to WT. Arg153-His variant showed 72-fold increase in thermostability (t 1/2 = 6 h) at 60 °C as compared to WT (t 1/2 = 5 min). Increase in thermostability might be contributed by the formation of additional hydrogen bonds between His153/AO-Arg106/ANH2 as well as His153-Arg106/ANE. The variant demonstrated broad substrate specificity. A maximum conversion of 59 and 62% was obtained for methyl oleate and methyl butyrate, respectively, using immobilized variant lipase, whereas immobilized WT enzyme synthesizes 35% methyl oleate. WT enzyme was unable to synthesize methyl butyrate as it showed negligible activity with pNP-butyrate.
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Texto completo:
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Bacillus
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Ácidos Oleicos
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Mutação Puntual
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Temperatura Alta
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Lipase
Idioma:
En
Ano de publicação:
2018
Tipo de documento:
Article