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The biological functions and metabolic pathways of valine in swine

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Journal of Animal Science and biotechnology 2024年第1期15卷 20-34页

作者： Chuni Wang Yao Peng Yiru Zhang Juan Xu Sheng Jiang Leli Wang Yulong Yin Institute of Subtropical Agriculture Chinese Academy of SciencesChangshaChina Hunan Provincial Key Laboratory of Animal Intestinal Function and Regulation College of Life SciencesHunan Normal UniversityChangshaChina tianjin Institute of industrial biotechnology Chinese Academy of SciencesTianjinChina

Valine is an essential amino acid and a type of branched-chain amino acid. Due to the involvement of branchedchain amino acids in various metabolic pathways, there has been a surge of interests in valine nutrition and its role in animal physiology. In pigs, the interactions between valine and other branched-chain amino acids or aromatic amino acids are complex. In this review, we delve into the interaction mechanism, metabolic pathways, and biological functions of valine. Appropriate valine supplementation not only enhances growth and reproductive performances, but also modulates gut microbiota and immune functions. Based on past observations and interpretations, we provide recommended feed levels of valine for weaned piglets, growing pigs, gilts, lactating sows, barrows and entire males. The summarized valine nutrient requirements for pigs at different stages offer valuable insights for future research and practical applications in animal husbandry.

关键词： Additional dosage Biological function Metabolic pathway Pig Valine

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Gut liver brain axis in diseases:the implications for therapeutic interventions

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Signal Transduction and Targeted Therapy 2024年第1期9卷 79-104页

作者： Mengyao Yan Shuli Man Benyue Sun Long Ma Lanping Guo Luqi Huang Wenyuan Gao State Key Laboratory of Food Nutrition and Safety Key Laboratory of Industrial MicrobiologyMinistry of EducationTianjin Key Laboratory of Industry MicrobiologyNational and Local United Engineering Lab of Metabolic Control Fermentation TechnologyChina International Science and Technology Cooperation Base of Food Nutrition/Safety and Medicinal ChemistryCollege of BiotechnologyTianjin University of Science&Technology300457 TianjinChina National Resource Center for Chinese Materia Medica China Academy of Chinese Medical Sciences100700 BeijingChina tianjin Key Laboratory for Modern Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityWeijin Road300072 TianjinChina

Gut-liver-brain axis is a three-way highway of information interaction system among the gastrointestinal tract,liver,and nervous systems.In the past few decades,breakthrough progress has been made in the gut liver brain axis,mainly through understanding its formation mechanism and increasing treatment strategies.In this review,we discuss various complex networks including barrier permeability,gut hormones,gut microbial metabolites,vagus nerve,neurotransmitters,immunity,brain toxic metabolites,β-amyloid(Aβ)metabolism,and epigenetic regulation in the gut-liver-brain axis.Some therapies containing antibiotics,probiotics,prebiotics,synbiotics,fecal microbiota transplantation(FMT),polyphenols,low FODMAP diet and nanotechnology application regulate the gut liver brain axis.Besides,some special treatments targeting gut-liver axis include farnesoid X receptor(FXR)agonists,takeda G protein-coupled receptor 5(TGR5)agonists,glucagon-like peptide-1(GLP-1)receptor antagonists and fibroblast growth factor 19(FGF19)analogs.Targeting gut-brain axis embraces cognitive behavioral therapy(CBT),antidepressants and tryptophan metabolism-related therapies.Targeting liver-brain axis contains epigenetic regulation and Aβmetabolism-related therapies.In the future,a better understanding of gut-liver-brain axis interactions will promote the development of novel preventative strategies and the discovery of precise therapeutic targets in multiple diseases.

关键词： metabolism therapeutic immunity

Continuous-flow enzymatic synthesis of chiral lactones in a three-dimensional microfluidic reactor

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Chinese Chemical Letters 2024年第3期35卷 299-303页

作者： Xuelei Deng Meng Fan Miao Wu Xiaoyan Zhang Ya Cheng Jianye Xia Yingping Zhuang Weiping Zhu Xuhong Qian Yunpeng Bai State Key Laboratory of Bioreactor Engineering Shanghai Collaborative Innovation Center for BiomanufacturingEast China University of Science and TechnologyShanghai 200237China The Extreme Optoelectromechanics Laboratory School of Physics and Materials ScienceEast China Normal UniversityShanghai 200241China tianjin Institute of industrial biotechnology Chinese Academy of SciencesTianjin 300308China

A new continuous-flow process for the enzymatic synthesis of optically pureγ-lactones,which are used as flavors and fragrances in the food and cosmetic industries,was developed in a three-dimensional microfluidic reactor.The microchannels(175 mm in length,0.9 mm in depth,and 1.72 mL in volume)were carved precisely inside a single borosilicate glass(90 mm×75 mm×12 mm)with ultrafast femtosecond laser micromachining.The flow field analysis and reaction simulation showed that the mixing of substrates and enzymes was enhanced,allowing the adjustment of residence time in a wide window.SmCR_(V4),a carbonyl reductase with excellent catalytic activity and enantioselectivity towardγ/δ-keto acids,was employed for the asymmetric synthesis of various chiral lactones.30 mmol/L(R)-γ-decalactone(3g)can be obtained in 26 s with a space-time yield(STY)up to 16,877 g L^(-1)d^(-1),which is 14.4 times higher than the highest STY of batch reaction reported previously.This continuous-flow process was applied to the synthesis of 6 chiral lactones.In addition,the scaled-up synthesis of 3g was carried out in 6 cascade microreactors continuously for 6 h,demonstrating the feasibility and stability of the 3D continuous-flow process in enzymatic synthesis of optically pure compounds.

关键词： Continuous-flow Flow chemistry Microreactor Biocatalysis Carbonyl reductase Asymmetric reduction

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Rational protein engineering of thermostable heparinase I from Bacteroides thetaiotaomicron for highly efficient heparin degradation

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Food Science and Human Wellness 2024年

作者： Chuan Zhang Ruohan Zhao Leilei Yu Qixiao Zhai Jianxin Zhao Hao Zhang Xuegang Luo Fengwei Tian Wei Chen State Key Laboratory of Food Science and Technology Jiangnan University School of Food Science and Technology Jiangnan University Key Laboratory of industrial Fermentation Microbiology of the Ministry of Education & tianjin Key Lab of industrial Microbiology College of biotechnology tianjin University of Science and Technology National Engineering Research Center for Functional Food Jiangnan University

Heparin， a glycosaminoglycan， is a stable source of carbon that supports the growth of microorganisms in the human intestine. It is also a commonly used anticoagulant drug in clinical practice， with significant therapeutic effects. Low molecular weight heparin （LMWH） is a highly active low molecular weight fragment obtained via enzymatic reaction or the chemical degradation of heparin. LMWH has been applied globally in the prevention and treatment of venous thromboembolism in thrombosis patients. Simultaneously， as a potential prebiotic， because of its low molecular weight， LMWH can be well degraded by the gut microbiota to maintain intestinal balance. Enzymatic heparin degradation has recently emerged as a viable disposal method for LMWH preparation; however， only very few benchmark enzymes have been thoroughly described and subjected to protein engineering to improve their properties over the past few years. The commercialization of enzymes will require the development of robustly engineered enzymes that meet the demands of industrial processes. Herein， we report a rational protein engineering strategy that includes molecular dynamic simulations of flexible amino acid mutations and disulfide bond screening. Several Bt-HepI mutants were obtained and screened for high thermal stability. We obtained the Bt-HepID204C/K208C/H189W/Q198Rvariant， which features a stabilized protein surface structure， with a 1.3-fold increase in kcat/Km， a 2.44-fold increase in thermal stability at 50℃， and a 1.8-fold decrease in the average molecular weight of LMWH produced at 40℃ compared with that seen with Bt-HepIWT. Our study establishes a strategy to engineer thermostable HepI to underpin its industrial applications.

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The protective effects of fermented vinegar on acute alcohol-induced hepatic and neuro-toxicity by regulating ethanol metabolism and gut microbiota

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Food Science and Human Wellness 2024年

作者： Yuan Meng Yunfan Liu Ting Xia Beibei Geng Yinglei Tian Hailong Cao Jin Yan Xiaoqi Pang Kai Liang Yufeng Yan Min Wang State Key Laboratory of Food Nutrition and Safety Key Laboratory of industrial Fermentation Microbiology College of biotechnology tianjin University of Science and Technology Department of Gastroenterology and Hepatology General Hospital tianjin Medical University National Key Clinical Specialty tianjin Institute of Digestive Diseases tianjin Key Laboratory of Digestive Diseases Shanxi Provincial Key Laboratory for Vinegar Fermentation Science and Engineering Shanxi Zilin Vinegar Industry Co. Ltd.

Alcohol abuse constitutes a significant health hazard， leading to various organ damage， notably the liver and brain. Shanxi aged vinegar (SAV) is one of the famous fermented and functional foods containing a variety of bioactive ingredients with beneficial effects on the human body. This study aimed to explore the potential protective effect of SAV in alleviating acute alcohol intoxication (AAI) in mice. It was found that SAV at 2.5 mg/kg BW effectively ameliorated the decline in behavioral abilities following alcohol consumption， characterized by a shortened sobering period. SAV reduces alcohol-induced liver damage by inhibiting hepatic function enzymes and oxidative stress levels. Additionally， SAV mitigated the overactivation of microglia and the downregulation of neurotransmitter levels (AchE， 5-HT， and DA)， thereby reducing ethanol-induced brain damage. Meanwhile， SAV significantly decreased concentrations of alcohol and acetaldehyde in the blood and increased ADH and ALDH activities in the liver， indicating enhancement of ethanol metabolism. Moreover， we found that some gut microbiota including Verrucomicrobiota， Akkermansia， and Enterococcus were downregulated after SAV treatment in mice with AAI. These bacteria showed a negative correlation with anti-oxidative markers (GSH and CAT) and enzymes related to ethanol metabolism pathways (ADH and ALDH)， and a positive correlation with hepatic function markers (ALT， AST， and MDA)， alcohol metabolites (alcohol and acetaldehyde) and neurotransmitters (AchE， 5-HT， and DA). However， Bacteroidota， norank＿f＿Muribaculaceae， and Alistipes exhibited the opposite direction. These findings suggest that SAV possesses protective effects against hepatic and neuro-toxicity， and could be a potential functional food for AAI prevention.

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可生物降解塑料取代传统塑料--对碳排放的影响

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Engineering 2024年第1期32卷 152-162页

作者： Guanyi Chen Jianyuan Li Yunan Sun Zhi Wang Gary ALeeke Christian Moretti Zhanjun Cheng Yuan Wang Ning Li Lan Mu Jinyu Li Junyu Tao Beibei Yan Li'an Hou Interdisciplinary Innovation Lab for Environment and Energy School of Mechanical Engineering&School of Biotechnology and Food ScienceTianjin University of CommerceTianjin 300134China School of Environmental Science and Engineering Tianjin UniversityTianjin 300350China School of Ecology and Environment Tibet UniversityLhasa 850012China tianjin Key Laboratory of Biomass Wastes UtilizationTianjin Engineering Research Center for Organic Wastes Safe Disposal and Energy UtilizationTianjin 300072China School of Chemical Engineering University of BirminghamBirmingham B152TTUK Department of Environmental Systems Science ETH ZürichZürich CH-8092Switzerland

In recent years,a great deal of attention has been focused on the environmental impact of plastics,includ-ing the carbon emissions related to plastics,which has promoted the application of biodegradable plas-tics.Countries worldwide have shown high interest in replacing traditional plastics with biodegradable plastics.However,no systematic comparison has been conducted on the carbon emissions of biodegrad-able versus traditional plastic products.This study evaluates the carbon emissions of traditional and biodegradable plastic products(BPPs)over four stages and briefly discusses environmental and economic perspectives.Four scenarios-namely,the traditional method,chemical recycling,industrial composting,and anaerobic digestion-are considered for the disposal of waste BPPs(WBPPs).The analysis takes China as a case study.The results show that the carbon emissions of 1000traditional plastic products(plastic bags,lunch boxes,cups,etc.)were52.09-150.36 carbon emissions equivalent of per kilogram(kg CO_(2)eq),with the stage of plastic production contributing 50.71%-50.77%.In comparison,1000 similar BPPs topped out at 21.06-56.86 kg CO_(2)eq,approximately 13.53%-62.19%lower than traditional plastic prod-ucts.The difference was mainly at the stages of plastic production and waste disposal,and the BPPs showed significant carbon reduction potential at the raw material acquisition stage.Waste disposal plays an important role in environmental impact,and composting and anaerobic digestion are considered to be preferable disposal methods for WBPPs.However,the high cost of biodegradable plastics is a challenge for their widespread use.This study has important reference significance for the sustainable development of the biodegradableplastics industry.

关键词： Carbon emissions Biodegradable plastics Different disposal scenarios Daily life consumption Environmental and economic discussion

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Melatonin biosynthesis pathways in nature and its production in engineered microorganisms

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Synthetic and Systems biotechnology 2022年第1期7卷 544-553页

作者： Xiaotong Xie Dongqin Ding Danyang Bai Yaru Zhu Wei Sun Yumei Sun Dawei Zhang Dalian Polytechnic University Dalian116000PR China tianjin institutes of industrial biotechnology Chinese Academy of SciencesTianjin300308PR China Biodesign Center Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308PR China tianjin University of science and technology Tianjin300308PR China

Melatonin is a biogenic amine that can be found in plants,animals and microorganism.The metabolic pathway of melatonin is different in various organisms,and biosynthetic endogenous melatonin acts as a molecular signal and antioxidant protection against external stress.Microbial synthesis pathways of melatonin are similar to those of animals but different from those of plants.At present,the method of using microorganism fermentation to produce melatonin is gradually prevailing,and exploring the biosynthetic pathway of melatonin to modify microorganism is becoming the mainstream,which has more advantages than traditional chemical synthesis.Here,we review recent advances in the synthesis,optimization of melatonin pathway.L-tryptophan is one of the two crucial precursors for the synthesis of melatonin,which can be produced through a four-step reaction.Enzymes involved in melatonin synthesis have low specificity and catalytic efficiency.Site-directed mutation,directed evolution or promotion of cofactor synthesis can enhance enzyme activity and increase the metabolic flow to promote microbial melatonin production.On the whole,the status and bottleneck of melatonin biosynthesis can be improved to a higher level,providing an effective reference for future microbial modification.

关键词： Melatonin Biosynthesis Plants Animals Microorganisms Metabolic modification Enzyme catalysis mechanism

Origin and evolution of the main starch biosynthetic enzymes

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Synthetic and Systems biotechnology 2023年第3期8卷 462-468页

作者： Hong Chang Jie Bai Hejian Zhang Rong Huang Huanyu Chu Qian Wang Hao Liu Jian Cheng Huifeng Jiang College of biotechnology Tianjin University of Science and TechnologyTianjin300457China Key Laboratory of Engineering Biology for Low-carbon Manufacturing Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China National Center of Technology Innovation for Synthetic Biology Tianjin300308China

Starch,a semi-crystalline energy storage form primarily found in plant plastids plays a crucial role in various food or no-food applications.Despite the starch biosynthetic pathway’s main enzymes have been characterized,their origin and evolution remained a subject of debate.In this study,we conducted the comprehensive phylogenetic and structural analysis of three types of starch biosynthetic enzymes:starch synthase(SS),starch branching enzyme(SBE)and isoamylase-type debranching enzyme(ISA)from 51,151 annotated genomes.Our findings provide valuable insights into the possible scenario for the origin and evolution of the starch biosynthetic pathway.Initially,the ancestor of SBE can be traced back to an unidentified bacterium that existed before the formation of the last eukaryotic common ancestor(LECA)via horizontal gene transfer(HGT).This transfer event likely provided the eukaryote ancestor with the ability to synthesize glycogen.Furthermore,during the emergence of Archaeplastida,one clade of SS was transferred from Deltaproteobacteria by HGT,while ISA and the other clade of SS originated from Chlamydiae through endosymbiosis gene transfer(EGT).Both these transfer events collectively contributed to the establishment of the original starch biosynthetic pathway.Subsequently,after the divergence of Viridiplantae from Rhodophyta,all three enzymes underwent multiple duplications and N-terminus extension domain modifications,resulting in the formation of functionally specialized isoforms and ultimately leading to the complete starch biosynthetic pathway.By shedding light on the evolutionary origins of key enzymes involved in the starch biosynthetic pathway,this study provides important insights into the evolutionary events of plants.

关键词： Origin Evolution Starch biosynthesis Starch synthase Starch branching enzyme Isoamylase-type debranching enzyme

Identification of neutral genome integration sites with high expression and high integration efficiency in Fusarium venenatum TB01

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Synthetic and Systems biotechnology 2023年第1期8卷 141-147页

作者： Sheng Tong Kexin An Wuxi Chen Mengdan Chai Yuanxia Sun Qinhong Wang Demao Li tianjin Key Laboratory for industrial Biological Systems and Bioprocessing Engineering Tianjin Institute of Industrial BiotechnologyChinese Academy of SciencesTianjin300308China National Innovation Centre for Synthetic Biology Tianjin300308China

CRISPR/Cas9-mediated homology-directed recombination is an efficient method to express target genes.Based on the above method,providing ideal neutral integration sites can ensure the reliable,stable,and high expression of target genes.In this study,we obtained a fluorescent transformant with neutral integration and high expression of the GFP expression cassette from the constructed GFP expression library and named strain FS.The integration site mapped at 4886 bp upstream of the gene FVRRES_00686 was identified in strain FS based on a Y-shaped adaptor-dependent extension,and the sequence containing 600 bp upstream and downstream of this site was selected as the candidate region for designing sgRNAs(Sites)for CRISPR/Cas9-mediated homology-directed recombination.PCR analysis showed that the integration efficiency of CRISPR/Cas9-mediated integration of target genes in designed sites reached 100%.Further expression stability and applicability analysis revealed that the integration of the target gene into the above designed sites can be stably inherited and expressed and has no negative effect on the growth of F.venenatum TB01.These results indicate the above designed neutral sites have the potential to accelerate the development of F.venenatum TB01 through overexpression of target genes in metabolic engineering.

关键词： GFP expression library Neutral integration site Y-shaped adaptor-dependent extension CRISPR/Cas9 Fusarium venenatum