DOAJ Open Access 2018

Property Improvement of α-Amylase from Bacillus stearothermophilus by Deletion of Amino Acid Residues Arginine 179 and Glycine 180

Yuanming Gai Jingqi Chen Shibin Zhang Beiwei Zhu Dawei Zhang

Abstrak

To improve the properties of α-amylase from Bacillus stearothermophilus (AmyS), a deletion mutant AmyS∆R179-G180 was constructed by deleting arginine (Arg179) and glycine (Gly180) using site-directed mutagenesis. AmyS and AmyS∆R179-G180 were expressed in Bacillus subtilis and purified by ammonium sulfate precipitation, after which the enzymatic properties were characterized and compared. By deleting amino acids Arg179 and Gly180, the thermostability of α-amylase AmyS∆R179-G180 was enhanced and the half-life at 100 °C significantly increased from 24 to 33 min. In addition, AmyS∆R179-G180 exhibited greater acid resistance and lower calcium requirements to maintain α-amylase activity. The secretory capacity of the recombinant strain was evaluated by fed-batch fermentation in a 7.5-litre fermentor in which high α-amylase activity was obtained. The highest activity reached 3300 U/mL with a high productivity of 45.8 U/(mL•h).

Topik & Kata Kunci

Biotechnology Food processing and manufacture

Penulis (5)

Yuanming Gai

Jingqi Chen

Shibin Zhang

Beiwei Zhu

Dawei Zhang

Format Sitasi

APA MLA BibTeX

Gai, Y., Chen, J., Zhang, S., Zhu, B., Zhang, D. (2018). Property Improvement of α-Amylase from Bacillus stearothermophilus by Deletion of Amino Acid Residues Arginine 179 and Glycine 180. https://doi.org/10.17113/ftb.56.01.18.5448

Akses Cepat

PDF tidak tersedia langsung

Cek di sumber asli →

Lihat di Sumber doi.org/10.17113/ftb.56.01.18.5448

Informasi Jurnal

Tahun Terbit: 2018
Sumber Database: DOAJ
DOI: 10.17113/ftb.56.01.18.5448
Akses: Open Access ✓