ACS Omega
·
2023
·
IF 4.1
Xingchang Cha,Juanjuan Ding,Wenyan Ba,Shengping You,Wei Qi,Rongxin Su
γ-Aminobutyric acid (GABA) is an inhibitory neurotransmitter with important physiological functions such as sleep assistance and anti-depression. In this study, we developed a fermentation process for the high-efficiency production of GABA by Lactobacillus brevis (Lb. brevis) CE701. First, xylose was found as the optimal carbon source that could improve the GABA production and OD600 in shake flasks to 40.35 g/L and 8.64, respectively, which were 1.78-fold and 1.67-fold of the glucose. Subsequently, the analysis of the carbon source metabolic pathway indicated that xylose activated the expression of the xyl operon, and xylose metabolism produced more ATP and organic acids than glucose, which significantly promoted the growth and GABA production of Lb. brevis CE701. Then, an efficient GABA fermentation process was developed by optimizing the medium components using response surface methodology. Finally, the production of GABA reached 176.04 g/L in a 5 L fermenter, which was 336% higher than that in a shake flask. This work enables the efficient synthesis of GABA using xylose, which will provide guidance for the industrial production of GABA.
研究领域:
微生物学
·
生物工程
·
食品科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2025
·
IF 8
Yao Yao,Yunshan Zhang,Binqing Xue,Weihua Chu
Mono-2-ethylhexyl phthalate (MEHP) is one of the major biologically active metabolites of phthalate plasticizers that pose a health threat to aquatic animals. In this study, we investigated the ecotoxicological effects of MEHP on liver damage and gut microbiota in crucian carp ( Carassius carassius ) and the mitigating effects of Lactobacillus brevis Lb-0401 as a dietary supplement. The results showed that MEHP induced hepatotoxicity and increased serum AST, ALT and triglyceride levels, while L. brevis Lb-0401 alleviated abnormalities in serum metabolic parameters and increased antioxidant enzymes (T-SOD, CAT, GSH-Px). Further transcriptome and microbiota analysis revealed that MEHP exposure caused hepatic glucose, lipid and purine metabolism disorders, inhibited energy production and disrupted gut microbial homeostasis. Administration of L. brevis Lb-0401 reversed all these changes. In conclusion, this study not only provides new mechanistic insights into the ecotoxicological effects of MEHP, but also suggests a potential strategy using intestinal autochthonous probiotic bacteria to mitigate the harmful effects of phthalate plasticisers on aquatic organisms.
研究领域:
生态毒理学
·
水生毒理学
·
微生物学
·
环境科学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF FOOD QUALITY
·
2025
·Vol. 2025
·期 1
·5049955
·
IF 2.9
Jiyou Wu,Xiaoguang Yang,Yuhua Yang
This study aims to investigate the potential anti-inflammatory and antioxidant properties of Lactobacillus brevis CQPC12 (LBCQPC12) to enhance brain, neural, and motor functioning in mice. Mice were given intraperitoneal injections of mixed antibiotics (5 mg/mL neomycin, 25 mg/mL vancomycin, 0.1 mg/mL amphotericin B, 10 mg/mL ampicillin, 5 mg/mL metronidazole, and 1.5 μg/mL lipopolysaccharide) to mimic human bodies. At the conclusion of the trial, the mice’s capacity to run for prolonged periods of time and swim with weight was assessed. Furthermore, hematoxylin–eosin (H&E) staining was employed to investigate pathological alterations in brain tissue; quantitative polymerase chain reaction (qPCR) was applied to discover inflammatory pathway genes and vascular endothelial growth factor (VEGF)-related expressions in the brain and skeletal muscle, and the liver index, serum, and brain oxidation, and inflammation indicators were found. The findings demonstrated that LBCQPC12 increased total superoxide dismutase (T-SOD), glutathione (GSH), and interleukin-10 (IL-10) levels while decreasing malondialdehyde (MDA), IL-6, and tumor necrosis factor alpha (TNF-α) levels in the serum and brain, as well as lengthening the mice’s weight-carrying swimming and running durations and lowering the liver index. LBCQPC12 boosted the expression of VEGF-A, glucose transporter 1 (GLUT-1), GLUT-4, and hypoxia-inducible factor-1 alpha (HIF-1α) mRNA in skeletal muscle as well as genes in the brain’s protein kinase B 1/cAMP-response element binding protein/brain-derived neurotrophic factor/extracellular regulated protein kinases 1 (AKT1/CREB/BDNF/ERK1) pathways. Finally, LBCQPC12 demonstrated potential utility in the creation of functional probiotics by reducing oxidative inflammation, skeletal muscle damage, and motor function in the central nervous system brought on by antibiotics.
研究领域:
微生物学
·
神经科学
·
药理学
✓ 已验证
产品关联
DOI
高影响因子
BIOTECHNOLOGY & BIOTECHNOLOGICAL EQUIPMENT
·
2017
·
IF 1.059
Sheng Hu,Xiang Zhang,Yi Lu,Yue-Cheng Lin,Dong-Fang Xie,Hui Fang,Jun Huang,Le-He Mei
An aspartate aminotransferase (AATase) gene from Lactobacillus brevis CGMCC 1306 was cloned, which contains a 1182-bp open reading frame coding for 393 amino acids (41.43 kDa). When expressed in Escherichia coli BL21 (DE3), the recombinant AATase was purified and subsequently characterized. The recombinant AATase can catalyse the conversion of L-Asp to L-Glu, and the kcat/Km was determined to be 25.5 (mmol/L)−1 s−1 for L-Asp and 207.8 m(mol/L)−1 s−1 for α-ketoglutarate. With optimum temperature as 25 ˚C, the AATase may be a novel and special psychrophilic enzyme which exhibited a good thermal stability below 55 ˚C. The conserved active site residue of AATase was identified as Lys237 by phylogenetic analysis. Secondary structure of the enzyme includes α-helix (39.2%), β-sheet (5.5%), β-turn (8.8%), and random coil (36.5%) by circular dichroism spectral analysis. Phase diagram for the fluorescence data analysis showed that guanidinium chloride-induced unfolding of AATase involved at least one intermediate.
研究领域:
微生物学
·
生物化学
·
酶学
·
分子生物学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2026
·
IF 8.7
Jiaying Ai,Jiajun Yan,Yuxin Zhang,Fuping Lu,Shuhong Mao,Yixun Jiang,Lei Li,Hui-Min Qin
Chemical tethering NAD + to GfADH enhances enzyme-cofactor spatial proximity. • The application of conjugate and NOX reduced the NAD + demand by 13-fold. • The NAD + -GfADH conjugate and NOX were co-fixed via sequential recruitment. • Co-immobilization enhanced enzyme stability with improved cofactor regeneration. The green biomanufacturing of high-value compounds is limited by enzyme instability and cofactor dependence. Herein, we developed a tailored multi-module immobilization strategy that integrated cofactor tethering with sequential multi-enzyme co-immobilization to facilitate the efficient conversion of allitol into D-allulose catalyzed by the Gluconobacter frateurii -derived dehydrogenase (GfADH). In this strategy, nicotinamide adenine dinucleotide (NAD + ) was covalently tethered to the surface of GfADH via a flexible linker, creating an NAD + -GfADH conjugate. Coupling the conjugate with NADH oxidase (NOX) established an efficient cofactor self-regenerating system, reducing the external NAD + demand by 13-fold. Furthermore, this conjugate was encapsulated within hybrid nanoflowers, thereby improving its reusability. To facilitate cofactor transfer, NOX was directionally recruited and colocalized with GfADH using the SpyTag/SpyCatcher system. The co-immobilized enzyme exhibited a high D-allulose yield of 88.7% from 110 mM allitol and retained 85.0% of its initial activity after 6–8 cycles. This work provides a valuable integrated strategy for cofactor regeneration and enzyme stabilization in cofactor-dependent biosynthesis. Download: Download high-res image (169KB) Download: Download full-size image
✓ 已验证
DOI
PubMed
高影响因子
BIOCHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 3.9
Juanjuan Ding,Wenyan Ba,Shengping You,Wei Qi,Rongxin Su
γ-aminobutyric acid (GABA) is an important inhibitory neurotransmitter in the brain with many physiological functions. Therefore, this work establishes an efficient biosynthesis process to achieve the high production of food-grade GABA. Firstly, we adopted a directional colorimetric screening method and then obtained the strain Lactobacillus brevis ( Lb. brevis) CGMCC 24975 with 22.61 g/L GABA in shake flasks, much higher than Lb. brevis ATCC 367 (3.07 g/L) due to its more efficient and stable expression of its glutamate decarboxylase (GAD) system. After exploring the effects of optimal fermentation conditions and oxygen on GABA production, we found that anaerobic fermentation could increase GABA production by up-regulating gad operon expression and activating GADase. Finally, we developed an oil-sealed anaerobic fermentation process with 157.90 g/L GABA in a 5 L bioreactor, which was 6.98-fold of that in shake flasks. This work includes a complete process from screening GABA-producing strains to developing efficient fermentation processes, laying the foundation for producing food-safe GABA.
研究领域:
微生物学
·
生物技术
·
食品科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）