Sheng wu gong cheng xue bao = Chinese journal of biotechnology最新文献

{"title":"[Expression and enzymatic characterization of a chitosanase with tolerance to a wide range of pH from <i>Bacillus atrophaeus</i>].","authors":"Wenjuan DU, Awagul Tursun, Zhiqin Dong, Huijuan Ma, Zhenghai Ma","doi":"10.13345/j.cjb.240178","DOIUrl":"https://doi.org/10.13345/j.cjb.240178","url":null,"abstract":"<p><p>To screen and identify a chitosanase with high stability, we cloned the chitosanase gene from <i>Bacillus atrophaeus</i> with a high protease yield from the barren saline-alkali soil and expressed this gene in <i>Escherichia coli</i>. The expressed chitosanase of <i>B</i>. <i>atrophaeus</i> (BA-CSN) was purified by nickel-affinity column chromatography. The properties including optimal temperature, optimal pH, substrate specificity, and kinetic parameters of BA-CSN were characterized. The results showed that BA-CSN had the molecular weight of 31.13 kDa, the optimal temperature of 55 ℃, the optimal pH 5.5, and good stability at temperatures below 45 ℃ and pH 4.0-9.0. BA-CSN also had good stability within 4 h of pH 3.0 and 10.0, be activated by K⁺, Na⁺, Mn²⁺, Ca²⁺, Mg²⁺, and Co²⁺, (especially by Mn²⁺), and be inhibited by Fe³⁺, Cu²⁺, and Ag⁺. BA-CSN showcased the highest relative activity in the hydrolysis of colloidal chitosan, and it had good hydrolysis ability for colloidal chitin. Under the optimal catalytic conditions, BA-CSN demonstrated the Michaelis constant <i>K</i>_m and maximum reaction rate <i>V</i>_max of 9.94 mg/mL and 26.624 μmoL/(mL·min), respectively, for colloidal chitosan. In short, BA-CSN has strong tolerance to acids and alkali, possessing broad industrial application prospects.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"352-362"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041866","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Preparation of multi-layer compound microcapsules and their application in self-healing of concrete cracks].","authors":"Jianmiao Xu, Yuanyuan Zhou, Feng Cheng, Zhiqiang Liu","doi":"10.13345/j.cjb.240406","DOIUrl":"https://doi.org/10.13345/j.cjb.240406","url":null,"abstract":"<p><p>Concrete is widely used in building construction, civil engineering, roads, bridges, etc., but concrete cracking remains a major issue in the engineering industry. To develop an effective and feasible concrete repair technology, this study combined microbial and microencapsulation technologies to prepare a multi-layer compound microcapsule using the piercing method. The formulation and drying method of microcapsules were optimized by taking their embedding rate and mechanical properties as evaluation criteria. The calcium transcrystallization process of microcapsules and the crystal form of products were characterized and compared with the calcium transcrystallization process in free cells. Finally, the effects of microcapsule incorporation on mechanical properties, impermeability, and self-healing performance of concrete specimens were then tested. The results showed that the air-dried multi-layer compound microcapsules, formulated with 1.0% wet cells of <i>Bacillus cereus</i>, 1.5% calcium chloride, 3.0% sodium alginate, 5.0% nutrients, 6.0% glycerol, 0.6% chitosan, and 2.0% urea, achieved an embedding rate of 95.3%, a rupture force of 60.0 N and a hardness of 150.8 N. These microcapsules can transform from a solid state to a flowing colloidal state when the microorganisms inside undergo a calcium formation reaction. Both the microcapsules and free cells produced stable calcite crystal forms of calcium carbonate through the calcium conversion reaction, with the microcapsules producing more uniform-sized particles, which are more conducive to accumulation in cracks, thereby enhancing the stability of repair. When microcapsules were incorporated into the concrete specimen at a content of 0.45%, the flexural strength of the specimen increased by 17.3%, and the compressive strength increased by 12.3%. In the water impermeability test, specimens with microcapsules demonstrated better impermeability compensation for the cement concrete than those with free cells. The self-healing effect of cracks proved that multi-layer compound microcapsules could completely repair cracks up to 0.7 mm wide, and a repair rate of 95% for 0.8 mm wide cracks. In this study, a multi-layer compound microcapsule was developed to protect microorganisms in concrete and provide nutrients required for their growth, which provided a new idea for microbial induced calcium carbonate precipitation in concrete crack repair.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"448-460"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143040745","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Regulatory roles of <i>DGAT</i> and <i>PDAT</i> genes in plant oil synthesis].","authors":"Yang Wu, Mengjuan Liu, Youning Wang, Dexiao Li, Yuhua Yang, Tingjun Zhang, Huiwen Zhou","doi":"10.13345/j.cjb.240376","DOIUrl":"https://doi.org/10.13345/j.cjb.240376","url":null,"abstract":"<p><p>There is a large gap between production and demand of plant oil in China, which leads to the heavy reliance on imports. Diacylglycerol acyltransferase (DGAT) and phospholipid: diacylglycerol acyltransferase (PDAT) are two key enzymes responsible for the synthesis of triacylglycerol, thereby affecting the yield and quality of plant oil. This paper comprehensively reviews the research progress in <i>DGAT</i> and <i>PDAT</i> in terms of their biological functions in plant oil synthesis, the molecular mechanisms of regulating plant lipid metabolism, growth, and development under stress, and their roles in driving oil synthesis under the background of synthetic biology. Furthermore, future research and application of <i>DGAT</i> and <i>PDAT</i> are prospected. This review aims to provide a basis for deeply understanding the molecular mechanism of plant oil synthesis and improving the quality and productivity of oil crops by the utilization of <i>DGAT</i> and <i>PDAT</i> genes.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"216-229"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143040998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Research progress and application of nanopores in single-molecule protein sensing].","authors":"Lingzhi Wu, Xingyue Luo, Haofeng Deng, Qianli Ma, Lihua Tang","doi":"10.13345/j.cjb.240237","DOIUrl":"https://doi.org/10.13345/j.cjb.240237","url":null,"abstract":"<p><p>Proteins are fundamental carriers as the structural elements and biochemically active entities responsible for catalysis, transport, and regulation. These functions are depending on the protein folding into precise three-dimensional structures, interacting with ligands, and conformational changes. This article reviews the recent progress of nanopores in single-molecule protein sensing, involving the identification of polypeptides and proteins, the conformation changes of protein folding, the molecular structure responsible to the pH of solutions, the molecular interactions, and protein sequencing. These studies provide clues to understand life activities and facilitate the early diagnosis of diseases and design of drugs for precise treatment.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"92-116"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041114","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Effects of exogenous additives on growth and high-value bioproducts accumulation of microalgae].","authors":"Yawei Wu, Fangzhong Wang, Lei Chen, Weiwen Zhang","doi":"10.13345/j.cjb.240335","DOIUrl":"https://doi.org/10.13345/j.cjb.240335","url":null,"abstract":"<p><p>With the rapid development of synthetic biology, genetic engineering, and molecular manipulation methods in recent years, microalgae, as representatives of microbial cell factories, have been widely used as hosts in the production of high-value bioproducts, such as oils, pigments, proteins, and biofuels, demonstrating promising prospects of application in biochemical energy, food and drugs, and environmental protection. Despite these advancements, the low production efficiency of microalgae limits their industrial application. In addition to strain improvement and culture condition optimization, the regulation by exogenous chemical additives serves as a promising optimization strategy. This method relies on straightforward phenotypic screening and circumvents the necessity for intricate understanding of molecular targets in the metabolic and catabolic pathways involved in the synthesis of bioproducts. It enables rapid yield increasing of high-value bioproducts from microalgae and obtaining the required phenotypes. Although studies have reported the use of alternatives means such as exogenous additives to improve the growth of microalgae and the yield of high-value bioproducts, the classification and summarization of the types, applications, targeted strains, and molecular mechanisms of these additives are not comprehensive. Here, we review the studies using chemical inducers or enhancers to improve cell growth and high-value bioproduct accumulation in microalgae in recent years. This paper focuses on the types of exogenous additives, the effects of exogenous additives and their combinations on microalgae growth and high-value bioproduct accumulation, and the molecular mechanisms of related effects. We aim to provide information for researchers to use methods of synthetic biology to develop suitable cell chassis and harness microalgae for industrial production.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"173-198"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041751","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Advances in the catalytic promiscuity of nitrilases].","authors":"Hongjuan Diao, Xinfan Lin, Renchao Zheng, Yuguo Zheng","doi":"10.13345/j.cjb.240265","DOIUrl":"https://doi.org/10.13345/j.cjb.240265","url":null,"abstract":"<p><p>As important biocatalysts, nitrilases can efficiently convert nitrile groups into acids and ammonia in a mild and eco-friendly manner, being widely used in the synthesis of important pharmaceutical intermediates. Early studies reported that nitrilases only had the hydrolysis activity of catalyzing the formation of corresponding carboxylic acid products from nitriles, showing catalytic specificity. However, recent studies have shown that some nitrilases exhibit the hydration activity for catalyzing the formation of amides from nitriles, showing catalytic promiscuity. The catalytic promiscuity of nitrilases has dual effects. On the one hand, the presence of amide by-products increases the difficulties and costs of subsequent separation and purification of carboxylic acid products. On the other hand, however, if the catalytic reaction pathways of nitrilases can be precisely regulated to reshape enzyme functions, the reactions catalyzed by nitrilases can be broadened to provide new ideas for the biosynthesis of high-value amides, which is crucial for the development of artificial enzymes and biocatalysis. This review summarized the research progress in the catalytic promiscuity of nitrilases and discussed the key regulatory factors that may affect the catalytic promiscuity of nitrilases from the evolutionary origin, catalytic domains, and catalytic mechanisms, hoping to provide reference and inspiration for the application of nitrilases in biocatalysis.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"131-147"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041815","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Construction and optimization of 1, 4-butanediamine biosensor based on transcriptional regulator PuuR].","authors":"Junjie Liu, Minmin Jiang, Tong Sun, Xiangxiang Sun, Yongcan Zhao, Mingxia Gu, Fuping Lu, Ming Li","doi":"10.13345/j.cjb.240158","DOIUrl":"https://doi.org/10.13345/j.cjb.240158","url":null,"abstract":"<p><p>Biosensors have become powerful tools for real-time monitoring of specific small molecules and precise control of gene expression in biological systems. High-throughput sensors for 1, 4-butanediamine biosynthesis can greatly improve the screening efficiency of high-yielding 1, 4-butanediamine strains. However, the strategies for adapting the characteristics of biosensors are still rarely studied, which limits the applicability of 1, 4-butanediamine biosensors. In this paper, we propose the development of a 1, 4-butanediamine biosensor based on the transcriptional regulator PuuR, whose homologous operator puuO is installed in the constitutive promoter P_gapA of <i>Escherichia coli</i> to control the expression of the downstream superfolder green fluorescent protein (sfGFP) as the reporter protein. Finally, the biosensor showed a stable linear relationship between the GFP/<i>OD</i>₆₀₀ value and the concentration of 1, 4-butanediamine when the concentration of 1, 4-butanediamine was 0-50 mmol/L. The promoters with different strengths in the <i>E</i>. <i>coli</i> genome were used to modify the 1, 4-butanediamine biosensor, and the functional properties of the PuuR-based 1, 4-butanediamine biosensor were explored and improved, which laid the groundwork for high-throughput screening of engineered strains highly producing 1, 4-butanediamine.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"437-447"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041845","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[A flavin-containing monooxygenase from <i>Schizosaccharomyces pombe</i>: characterization and application in the synthesis of <i>S</i>-methyl-L-cysteine sulfoxide].","authors":"Mengka Lian, Zhaolin Song, Wenjing Gao, Gang Zhu, Mengjun Dong, Yu Li, Yihan Liu, Fenghua Wang, Fuping Lu","doi":"10.13345/j.cjb.240324","DOIUrl":"https://doi.org/10.13345/j.cjb.240324","url":null,"abstract":"<p><p><i>S</i>-methyl-L-cysteine sulfoxide (SMCO) is a non-protein sulfur-containing amino acid with a variety of functions. There are few reports on the enzymes catalyzing the biosynthesis of SMCO from <i>S</i>-methyl-L-cysteine (SMC). In this study, the flavin-containing monooxygenase gene derived from <i>Schizosaccharomyces pombe</i> (<i>spfmo</i>) was heterologously expressed in <i>Escherichia coli</i> BL21(DE3) and the enzymatic properties of the expressed protein were analyzed. The optimum catalytic conditions of the recombinant SpFMO were 30 ℃ and pH 8.0, under which the enzyme activity reached 72.77 U/g. An appropriate amount of Mg²⁺ improved the enzyme activity. The enzyme kinetic analysis showed that the <i>K</i>_m and <i>k</i>_cat/<i>K</i>_m of SpFMO on the substrate SMC were 23.89 μmol/L and 61.71 L/(min·mmol), respectively. Under the optimal reaction conditions, the yield of SMCO synthesized from SMC catalyzed by SpFMO was 12.31% within 9 h. This study provides reference for the enzymatic synthesis of SMCO.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"474-485"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041811","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Engineering of CmpLs enhances L-glutamate production of <i>Corynebacterium glutamicum</i>].","authors":"Xingtao Zuo, Shasha Zhong, Ningyun Cai, Tuo Shi, Zhidan Zhang, Yuantao Liu, Jiao Liu, Depei Wang, Jiuzhou Chen, Ping Zheng","doi":"10.13345/j.cjb.240306","DOIUrl":"https://doi.org/10.13345/j.cjb.240306","url":null,"abstract":"<p><p>The efficient production of L-glutamate is dependent on the product's rapid efflux, hence researchers have recently concentrated on artificially modifying its transport system and cell membrane wall structure. Considering the unique composition and structure of the cell wall of <i>Corynebacterium glutamicum</i>, we investigated the effects of CmpLs on L-glutamate synthesis and transport in SCgGC7, a constitutive L-glutamate efflux strain. First, the knockout strains of CmpLs were constructed, and it was confirmed that the deletion of CmpL1 and CmpL4 significantly improved the performance of L-glutamate producers. Next, temperature-sensitive L-glutamate fermentation with the CmpL1 and CmpL4 knockout strains were carried out in 5 L bioreactors, where the knockout strains showcased temperature-sensitive characteristics and enhanced capacities for L-glutamate production under high temperatures. Notably, the CmpL1 knockout strain outperformed the control strain in terms of L-glutamate production, showing production and yield increases of 69.2% and 55.3%, respectively. Finally, the intracellular and extracellular metabolites collected at the end of the fermentation process were analyzed. The modification of CmpLs greatly improved the L-glutamate excretion and metabolic flux for both L-glutamate production and transport. Additionally, the CmpL1 knockout strain showed decreased accumulation of downstream metabolites of L-glutamate and intermediate metabolites of tricarboxylic acid (TCA) cycle, which were consistent with its high L-glutamate biosynthesis capacity. In addition to offering an ideal target for improving the stability and performance of the industrial strains for L-glutamate production, the functional complementarity and redundancy of CmpLs provide a novel target and method for improving the transport of other metabolites by modification of the cell membrane and cell wall structures in <i>C. glutamicum</i>.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"271-287"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143041860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"[Improvement of catalytic activity and thermostability of glucose oxidase from <i>Aspergillus heteromorphus</i>].","authors":"Shanglin Yu, Qiao Zhou, Honghai Zhang, Yingguo Bai, Huiying Luo, Xiaojun Yang, Bin Yao","doi":"10.13345/j.cjb.240458","DOIUrl":"https://doi.org/10.13345/j.cjb.240458","url":null,"abstract":"<p><p>Glucose oxidase (GOD) is an oxygen-consuming dehydrogenase that can catalyze the production of gluconic acid hydrogen peroxide from glucose, and its specific mechanism of action makes it promising for applications, while the low catalytic activity and poor thermostability have become the main factors limiting the industrial application of this enzyme. In this study, we used the glucose oxidase <i>At</i>GOD reported with the best thermostability as the source sequence for phylogenetic analysis to obtain the GOD with excellent performance. Six genes were screened and successfully synthesized for functional validation. Among them, the glucose oxidase <i>Ah</i>GODB derived from <i>Aspergillus heteromorphus</i> was expressed in <i>Pichia pastoris</i> and showed better thermostability and catalytic activity, with an optimal temperature of 40 ℃, a specific activity of 112.2 U/mg, and a relative activity of 47% after 5 min of treatment at 70 ℃. To improve its activity and thermal stability, we constructed several mutants by directed evolution combined with rational design. Compared with the original enzyme, the mutant T72R/A153P showcased the optimum temperature increasing from 40 to 50 ℃, the specific activity increasing from 112.2 U/mg to 166.1 U/mg, and the relative activity after treatment at 70 ℃ for 30 min increasing from 0% to 33%. In conclusion, the glucose oxidase mutants obtained in this study have improved catalytic activity and thermostability, and have potential for application.</p>","PeriodicalId":21778,"journal":{"name":"Sheng wu gong cheng xue bao = Chinese journal of biotechnology","volume":"41 1","pages":"296-307"},"PeriodicalIF":0.0,"publicationDate":"2025-01-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143060608","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}