Yuanyuan Ren1, Baiqi Huang, Yonghong Meng, Lina Wei, Chen Zhang. 1. College of Food Engineering and Nutritional Science, Shaanxi Normal University, 199 South Chang'an Road, Xi'an, 710062, People's Republic of China, 840379817@qq.com.
Abstract
OBJECTIVES: Nitrogen metabolism was investigated during poly-γ-glutamic acid (γ-PGA) synthesis and phylogenetic analyses was used to explore glutamate dependency in Bacillus subtilis HSF1410. RESULTS: Bacillus subtilis HSF1410 was cultured with (15)NH4+ in the medium, and the γ-PGA synthesized was then analyzed using (15)N-NMR. The γ-PGA framework was partially labeled with (15)N, indicating that γ-PGA was synthesized from inorganic nitrogen and carbohydrate. Assay of glutamate synthetase and glutamine synthetase activities also revealed that ammonium can be used to synthesize γ-PGA in HSF1410. Phylogenetic trees based on γ-PGA synthesis genes (pgsBCA) and 16S rRNA showed that HSF1410 falls within a cluster of glutamate-dependent strains, versus glutamate-independent strains, which is confirmed by HSF1410 being unable to produce γ-PGA without glutamate in its medium CONCLUSION: we classify B. subtilis HSF1410 as a glutamate-dependent strain that can use exogenous inorganic nitrogen sources to synthesize γ-PGA.
OBJECTIVES:Nitrogen metabolism was investigated during poly-γ-glutamic acid (γ-PGA) synthesis and phylogenetic analyses was used to explore glutamate dependency in Bacillus subtilis HSF1410. RESULTS:Bacillus subtilis HSF1410 was cultured with (15)NH4+ in the medium, and the γ-PGA synthesized was then analyzed using (15)N-NMR. The γ-PGA framework was partially labeled with (15)N, indicating that γ-PGA was synthesized from inorganic nitrogen and carbohydrate. Assay of glutamate synthetase and glutamine synthetase activities also revealed that ammonium can be used to synthesize γ-PGA in HSF1410. Phylogenetic trees based on γ-PGA synthesis genes (pgsBCA) and 16S rRNA showed that HSF1410 falls within a cluster of glutamate-dependent strains, versus glutamate-independent strains, which is confirmed by HSF1410 being unable to produce γ-PGA without glutamate in its medium CONCLUSION: we classify B. subtilis HSF1410 as a glutamate-dependent strain that can use exogenous inorganic nitrogen sources to synthesize γ-PGA.
Authors: Naling Bai; Yu He; Hanlin Zhang; Xianqing Zheng; Rong Zeng; Yi Li; Shuangxi Li; Weiguang Lv Journal: Int J Environ Res Public Health Date: 2022-06-22 Impact factor: 4.614