Biotechnology and Bioprocess Engineering 2021; 26(4): 630-640  
Combining Genome Shuffling with Streptomycin Resistance to Improve Poly-γ-L-diaminobutanoic Acid Production in Bacillus pumilus
Shu Li, Liang Wang, Nan Wang, and Wei Cong
Shu Li*, Wei Cong
Marine College, Shandong University, Weihai 264209, China
Tel: +86-06315688303
E-mail: lishu2016@sdu.edu.cn
Liang Wang
The KeyLaboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China
Nan Wang
Weihai Food and Drug Administration, Testing Center, Weihai 264210, China
Received: September 28, 2020; Revised: November 2, 2020; Accepted: November 5, 2020; Published online: August 30, 2021.
© The Korean Society for Biotechnology and Bioengineering. All rights reserved.

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0/) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.
Abstract
A breeding approach combining genome shuffling with streptomycin resistance was developed in this research to improve the poly-γ-L-diaminobutanoic acid (γ-PAB) production in Bacillus pumilus LS-1. By this unique strategy, recombinants from the third round of genome shuffling could tolerate 18 μg/L of streptomycin and exhibited higher γ-PAB yield as 152.2 mg/L in shakeflask fermentation, 3-fold over the parent. In batch fermentation, B. pumilus GS3-9 could produce γ-PAB as high as 1284.7 mg/L in two days, 2.4-fold higher than the control, which was the highest productivity ever reported. In addition, the optimal pH in B. pumilus for γ-PAB synthesis was changed after atmospheric and room temperature plasma (ARTP) mutagenesis and protoplast fusion, because lower pH environment is favorable for accumulation of intracellular ATP. Some key enzymes in GS3-9 showed higher activities than those in parent, suggesting a greater flux to TCA circle and DAP pathway, which was a reason for enhanced γ-PAB production.
Keywords: poly-γ-L-diaminobutanoic acid, genome shuffling, streptomycin resistance, fermentation


This Article


Cited By Articles
  • CrossRef (0)

Services
Social Network Service

Archives