Pub Date : 2024-12-31Epub Date: 2024-01-12DOI: 10.1080/21645698.2023.2293510
Graham Brookes, Stuart J Smyth
This paper explores the scope for the newly emerging technologies, based on gene editing (GE) contributing to addressing the global challenges that we face. These challenges relate to food security, climate change and biodiversity depletion. In particular, it examines the science and evidence behind the most appropriate forms of agricultural production to meet these challenges, the targets set in the Global Biodiversity Framework (GBF) agreed to at the end of 2022 and the possible role of GE technologies in contributing to meeting these targets. It then examines the most risk-appropriate regulatory environment required to best facilitate the adoption of GE technology, drawing on the experiences of the impact of regulatory systems for other innovations used in agricultural and food production systems such as genetically modified organisms (GMOs).
本文探讨了基于基因编辑(GE)的新兴技术在应对我们面临的全球挑战方面的应用范围。这些挑战涉及粮食安全、气候变化和生物多样性枯竭。本文特别探讨了应对这些挑战的最合适的农业生产形式背后的科学和证据、2022 年底商定的全球生物多样性框架(GBF)中设定的目标,以及基因编辑技术在促进实现这些目标方面可能发挥的作用。然后,本报告借鉴转基因生物 (GMO) 等其他农业和食品生产系统创新监管制度的影响经验,探讨了最有利于采用 GE 技术所需的风险最适当的监管环境。
{"title":"Risk-appropriate regulations for gene-editing technologies.","authors":"Graham Brookes, Stuart J Smyth","doi":"10.1080/21645698.2023.2293510","DOIUrl":"10.1080/21645698.2023.2293510","url":null,"abstract":"<p><p>This paper explores the scope for the newly emerging technologies, based on gene editing (GE) contributing to addressing the global challenges that we face. These challenges relate to food security, climate change and biodiversity depletion. In particular, it examines the science and evidence behind the most appropriate forms of agricultural production to meet these challenges, the targets set in the Global Biodiversity Framework (GBF) agreed to at the end of 2022 and the possible role of GE technologies in contributing to meeting these targets. It then examines the most risk-appropriate regulatory environment required to best facilitate the adoption of GE technology, drawing on the experiences of the impact of regulatory systems for other innovations used in agricultural and food production systems such as genetically modified organisms (GMOs).</p>","PeriodicalId":54282,"journal":{"name":"Gm Crops & Food-Biotechnology in Agriculture and the Food Chain","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10793663/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139432592","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31Epub Date: 2024-07-04DOI: 10.1080/21645698.2024.2375664
Bongani Z Nkhabindze, Cebisile N Magagula, Diana Earnshaw, Calsile F Mhlanga, Sipho N Matsebula, Isaac G Dladla
The Kingdom of Eswatini is a Party to the Convention on Biological Diversity and to the Cartagena Protocol on Biosafety. As Party, Eswatini has domesticated these agreements by passing the Biosafety Act, of 2012 to provide for the safe handling, transfer, and use of living modified organisms (LMOs) in the country. The Act regulates living modified organisms to be used for confined field trials, commercial release, import, export, and transit, and for food, feed, and processing. Guidance is provided for prospective applicants before any application is made to the Competent Authority. This framework also provides for the regulation of emerging technologies such as synthetic biology and genome editing. The regulatory framework for living modified organisms aims to provide an enabling environment for the precautionary use of modern biotechnology and its products in the country in order to safeguard biological diversity and human health.
{"title":"Regulatory framework for genetically modified organisms in the Kingdom of Eswatini.","authors":"Bongani Z Nkhabindze, Cebisile N Magagula, Diana Earnshaw, Calsile F Mhlanga, Sipho N Matsebula, Isaac G Dladla","doi":"10.1080/21645698.2024.2375664","DOIUrl":"https://doi.org/10.1080/21645698.2024.2375664","url":null,"abstract":"<p><p>The Kingdom of Eswatini is a Party to the Convention on Biological Diversity and to the Cartagena Protocol on Biosafety. As Party, Eswatini has domesticated these agreements by passing the Biosafety Act, of 2012 to provide for the safe handling, transfer, and use of living modified organisms (LMOs) in the country. The Act regulates living modified organisms to be used for confined field trials, commercial release, import, export, and transit, and for food, feed, and processing. Guidance is provided for prospective applicants before any application is made to the Competent Authority. This framework also provides for the regulation of emerging technologies such as synthetic biology and genome editing. The regulatory framework for living modified organisms aims to provide an enabling environment for the precautionary use of modern biotechnology and its products in the country in order to safeguard biological diversity and human health.</p>","PeriodicalId":54282,"journal":{"name":"Gm Crops & Food-Biotechnology in Agriculture and the Food Chain","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141535957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-31Epub Date: 2024-03-12DOI: 10.1080/21645698.2024.2305944
Richard E Goodman
Since the first genetically engineered or modified crops or organisms (GMO) were approved for commercial production in 1995, no new GMO has been proven to be a hazard or cause harm to human consumers. These modifications have improved crop efficiency, reduced losses to insect pests, reduced losses to viral and microbial plant pathogens and improved drought tolerance. A few have focused on nutritional improvements producing beta carotene in Golden Rice. Regulators in the United States and countries signing the CODEX Alimentarius and Cartagena Biosafety agreements have evaluated human and animal food safety considering potential risks of allergenicity, toxicity, nutritional and anti-nutritional risks. They consider risks for non-target organisms and the environment. There are no cases where post-market surveillance has uncovered harm to consumers or the environment including potential transfer of DNA from the GMO to non-target organisms. In fact, many GMOs have helped improve production, yield and reduced risks from chemical insecticides or fungicides. Yet there are generic calls to label foods containing any genetic modification as a GMO and refusing to allow GM events to be labeled as organic. Many African countries have accepted the Cartagena Protocol as a tool to keep GM events out of their countries while facing food insecurity. The rationale for those restrictions are not rational. Other issues related to genetic diversity, seed production and environmental safety must be addressed. What can be done to increase acceptance of safe and nutritious foods as the population increases, land for cultivation is reduced and energy costs soar?
自 1995 年第一批转基因或改良作物或生物(GMO)被批准用于商业生产以来,还没有任何新的转基因生物被证明对人类消费者造成危害或伤害。这些改造提高了作物的效率,减少了虫害造成的损失,减少了病毒和微生物植物病原体造成的损失,并提高了耐旱性。少数改良侧重于营养方面,如在黄金大米中添加胡萝卜素。美国和签署 CODEX Alimentarius 和 Cartagena 生物安全协议的国家的监管机构对人类和动物食品安全进行了评估,考虑了过敏性、毒性、营养和抗营养风险等潜在风险。它们还考虑了对非目标生物和环境的风险。没有上市后监测发现对消费者或环境造成伤害的案例,包括转基因生物的 DNA 可能转移到非目标生物。事实上,许多转基因生物有助于提高产量和收益,降低化学杀虫剂或杀真菌剂的风险。然而,人们普遍呼吁将含有任何转基因成分的食品标为转基因生物,并拒绝允许将转基因食品标为有机食品。许多非洲国家接受了《卡塔赫纳议定书》,将其作为一种工具,在面临粮食不安全的情况下将转基因事件拒之门外。这些限制的理由并不合理。必须解决与遗传多样性、种子生产和环境安全有关的其他问题。在人口增加、耕地减少、能源成本飙升的情况下,如何才能提高人们对安全营养食品的接受程度?
{"title":"Twenty-eight years of GM Food and feed without harm: why not accept them?","authors":"Richard E Goodman","doi":"10.1080/21645698.2024.2305944","DOIUrl":"10.1080/21645698.2024.2305944","url":null,"abstract":"<p><p>Since the first genetically engineered or modified crops or organisms (GMO) were approved for commercial production in 1995, no new GMO has been proven to be a hazard or cause harm to human consumers. These modifications have improved crop efficiency, reduced losses to insect pests, reduced losses to viral and microbial plant pathogens and improved drought tolerance. A few have focused on nutritional improvements producing beta carotene in Golden Rice. Regulators in the United States and countries signing the CODEX Alimentarius and Cartagena Biosafety agreements have evaluated human and animal food safety considering potential risks of allergenicity, toxicity, nutritional and anti-nutritional risks. They consider risks for non-target organisms and the environment. There are no cases where post-market surveillance has uncovered harm to consumers or the environment including potential transfer of DNA from the GMO to non-target organisms. In fact, many GMOs have helped improve production, yield and reduced risks from chemical insecticides or fungicides. Yet there are generic calls to label foods containing any genetic modification as a GMO and refusing to allow GM events to be labeled as organic. Many African countries have accepted the Cartagena Protocol as a tool to keep GM events out of their countries while facing food insecurity. The rationale for those restrictions are not rational. Other issues related to genetic diversity, seed production and environmental safety must be addressed. What can be done to increase acceptance of safe and nutritious foods as the population increases, land for cultivation is reduced and energy costs soar?</p>","PeriodicalId":54282,"journal":{"name":"Gm Crops & Food-Biotechnology in Agriculture and the Food Chain","volume":null,"pages":null},"PeriodicalIF":3.9,"publicationDate":"2024-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10939142/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140112193","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01Epub Date: 2024-01-06DOI: 10.1007/s00253-023-12829-1
Younggun Yoon, Azilah Abd Aziz, In Seop Chang, Bongkyu Kim
For a better understanding of the distribution of depth-dependent electrochemically active bacteria at in the anode zone, a customized system in a microbial fuel cell (MFC) packed with granular activated carbon (GAC) was developed and subsequently optimized via electrochemical tests. The constructed MFC system was sequentially operated using two types of matrice solutions: artificially controlled compositions (i.e., artificial wastewater, AW) and solutions obtained directly from actual sewage-treating municipal plants (i.e., municipal wastewater, MW). Notably, significant difference(s) of system efficiencies between AW or MW matrices were observed via performance tests, in that the electricity production capacity under MW matrices is < 25% that of the AW matrices. Interestingly, species of Escherichia coli (E. coli) sampled from the GAC bed (P1: deeper region in GAC bed, P2: shallow region of GAC near electrolytes) exhibited an average relative abundance of 75 to 90% in AW and a relative abundance of approximately 10% in MW, while a lower relative abundance of E. coli was found in both the AW and MW anolyte samples (L). Moreover, similar bacterial communities were identified in samples P1 and P2 for both the AW and MW solutions, indicating a comparable distribution of bacterial communities over the anode area. These results provide new insights into E. coli contribution in power production for the GAC-packed MFC systems (i.e., despite the low contents of Geobacter (> 8%) and Shewanella (> 1%)) for future applications in sustainable energy research. KEY POINTS: • A microbial community analysis for depth-dependence in biofilm was developed. • The system was operated with two matrices; electrochemical performance was assessed. • E. coli spp. was distinctly found in anode zone layers composed of activated carbon.
{"title":"Prevalence of Escherichia coli in electrogenic biofilm on activated carbon in microbial fuel cell.","authors":"Younggun Yoon, Azilah Abd Aziz, In Seop Chang, Bongkyu Kim","doi":"10.1007/s00253-023-12829-1","DOIUrl":"10.1007/s00253-023-12829-1","url":null,"abstract":"<p><p>For a better understanding of the distribution of depth-dependent electrochemically active bacteria at in the anode zone, a customized system in a microbial fuel cell (MFC) packed with granular activated carbon (GAC) was developed and subsequently optimized via electrochemical tests. The constructed MFC system was sequentially operated using two types of matrice solutions: artificially controlled compositions (i.e., artificial wastewater, AW) and solutions obtained directly from actual sewage-treating municipal plants (i.e., municipal wastewater, MW). Notably, significant difference(s) of system efficiencies between AW or MW matrices were observed via performance tests, in that the electricity production capacity under MW matrices is < 25% that of the AW matrices. Interestingly, species of Escherichia coli (E. coli) sampled from the GAC bed (P1: deeper region in GAC bed, P2: shallow region of GAC near electrolytes) exhibited an average relative abundance of 75 to 90% in AW and a relative abundance of approximately 10% in MW, while a lower relative abundance of E. coli was found in both the AW and MW anolyte samples (L). Moreover, similar bacterial communities were identified in samples P1 and P2 for both the AW and MW solutions, indicating a comparable distribution of bacterial communities over the anode area. These results provide new insights into E. coli contribution in power production for the GAC-packed MFC systems (i.e., despite the low contents of Geobacter (> 8%) and Shewanella (> 1%)) for future applications in sustainable energy research. KEY POINTS: • A microbial community analysis for depth-dependence in biofilm was developed. • The system was operated with two matrices; electrochemical performance was assessed. • E. coli spp. was distinctly found in anode zone layers composed of activated carbon.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139110719","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01DOI: 10.1007/s00253-023-12905-6
Syed Bilal Shah, Yiting Wang, Naveed Anwar, Syed Zaghum Abbas, Khalid Ali Khan, Song-Mei Wang, Muhammad Wajid Ullah
Abstract
Hexabromocyclododecane (HBCD) is a widely used brominated flame retardant; however, it is a persistent organic pollutant as well as affects the human thyroid hormones and causes cancer. However, the degradation of HBCD has received little attention from researchers. Due to its bioaccumulative and hazardous properties, an appropriate strategy for its remediation is required. In this study, we investigated the biodegradation of HBCD using Shewanella oneidensis MR-1 under optimized conditions. The Box-Behnken design (BBD) was implemented for the optimization of the physical degradation parameters of HBCD. S. oneidensis MR-1 showed the best degradation performance at a temperature of 30 °C, pH 7, and agitation speed of 115 rpm, with an HBCD concentration of 1125 μg/L in mineral salt medium (MSM). The strain tolerated up to 2000 μg/L HBCD. Gas chromatography-mass spectrometry analysis identified three intermediates, including 2-bromo dodecane, 2,7,10-trimethyldodecane, and 4-methyl-1-decene. The results provide an insightful understanding of the biodegradation of HBCD by S. oneidensis MR-1 under optimized conditions and could pave the way for further eco-friendly applications.
Key points
• HBCD biodegradation by Shewanella oneidensis
• Optimization of HBCD biodegradation by the Box-Behnken analysis
• Identification of useful metabolites from HBCD degradation
{"title":"Co-metabolic degradation and metabolite detection of hexabromocyclododecane by Shewanella oneidensis MR-1","authors":"Syed Bilal Shah, Yiting Wang, Naveed Anwar, Syed Zaghum Abbas, Khalid Ali Khan, Song-Mei Wang, Muhammad Wajid Ullah","doi":"10.1007/s00253-023-12905-6","DOIUrl":"https://doi.org/10.1007/s00253-023-12905-6","url":null,"abstract":"<span> <h3>Abstract</h3> <p>Hexabromocyclododecane (HBCD) is a widely used brominated flame retardant; however, it is a persistent organic pollutant as well as affects the human thyroid hormones and causes cancer. However, the degradation of HBCD has received little attention from researchers. Due to its bioaccumulative and hazardous properties, an appropriate strategy for its remediation is required. In this study, we investigated the biodegradation of HBCD using <em>Shewanella oneidensis</em> MR-1 under optimized conditions. The Box-Behnken design (BBD) was implemented for the optimization of the physical degradation parameters of HBCD. <em>S. oneidensis</em> MR-1 showed the best degradation performance at a temperature of 30 °C, pH 7, and agitation speed of 115 rpm, with an HBCD concentration of 1125 μg/L in mineral salt medium (MSM). The strain tolerated up to 2000 μg/L HBCD. Gas chromatography-mass spectrometry analysis identified three intermediates, including 2-bromo dodecane, 2,7,10-trimethyldodecane, and 4-methyl-1-decene. The results provide an insightful understanding of the biodegradation of HBCD by <em>S. oneidensis</em> MR-1 under optimized conditions and could pave the way for further eco-friendly applications.</p> </span> <span> <h3>Key points</h3> <p>• <em>HBCD biodegradation by Shewanella oneidensis</em></p> <p>• <em>Optimization of HBCD biodegradation by the Box-Behnken analysis</em></p> <p>• <em>Identification of useful metabolites from HBCD degradation</em></p> </span>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139068011","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Veillonella spp. are Gram-negative opportunistic pathogens present in the respiratory, digestive, and reproductive tracts of mammals. An abnormal increase in Veillonella relative abundance in the body is closely associated with periodontitis, inflammatory bowel disease, urinary tract infections, and many other diseases. We designed a pair of primers and a probe based on the 16S rRNA gene sequences of Veillonella and conducted real-time quantitative PCR (qPCR) and droplet digital PCR (ddPCR) to quantify the abundance of Veillonella in fecal samples. These two methods were tested for specificity and sensitivity using simulated clinical samples. The sensitivity of qPCR was 100 copies/μL, allowing for the accurate detection of a wide range of Veillonella concentrations from 103 to 108 CFU/mL. The sensitivity of ddPCR was 11.3 copies/μL, only allowing for the accurate detection of Veillonella concentrations from 101 to 104 CFU/mL because of the limited number of droplets generated by ddPCR. ddPCR is therefore more suitable for the detection of low-abundance Veillonella samples. To characterize the validity of the assay system, clinical samples from children with inflammatory bowel disease were collected and analyzed, and the results were verified using isolation methods. We conclude that molecular assays targeting the 16S rRNA gene provides an important tool for the rapid diagnosis of chronic and infectious diseases caused by Veillonella and also supports the isolation and identification of Veillonella for research purposes. KEY POINTS: • With suitable primer sets, the qPCR has a wider detection range than ddPCR. • ddPCR is suitable for the detection of low-abundance samples. • Methods successfully guided the isolation of Veillonella in clinical sample.
{"title":"Detecting and quantifying Veillonella by real-time quantitative PCR and droplet digital PCR.","authors":"Zanbo Ding, Jinghua Cui, Qun Zhang, Junxia Feng, Bing Du, Guanhua Xue, Chao Yan, Lin Gan, Zheng Fan, Yanling Feng, Hanqing Zhao, Ziying Xu, Zihui Yu, Tongtong Fu, Rui Zhang, Xiaohu Cui, Ziyan Tian, Jinfeng Chen, Yujie Chen, Zhoufei Li, Xuemei Zhong, Yanbing Lin, Jing Yuan","doi":"10.1007/s00253-023-12861-1","DOIUrl":"10.1007/s00253-023-12861-1","url":null,"abstract":"<p><p>Veillonella spp. are Gram-negative opportunistic pathogens present in the respiratory, digestive, and reproductive tracts of mammals. An abnormal increase in Veillonella relative abundance in the body is closely associated with periodontitis, inflammatory bowel disease, urinary tract infections, and many other diseases. We designed a pair of primers and a probe based on the 16S rRNA gene sequences of Veillonella and conducted real-time quantitative PCR (qPCR) and droplet digital PCR (ddPCR) to quantify the abundance of Veillonella in fecal samples. These two methods were tested for specificity and sensitivity using simulated clinical samples. The sensitivity of qPCR was 100 copies/μL, allowing for the accurate detection of a wide range of Veillonella concentrations from 10<sup>3</sup> to 10<sup>8</sup> CFU/mL. The sensitivity of ddPCR was 11.3 copies/μL, only allowing for the accurate detection of Veillonella concentrations from 10<sup>1</sup> to 10<sup>4</sup> CFU/mL because of the limited number of droplets generated by ddPCR. ddPCR is therefore more suitable for the detection of low-abundance Veillonella samples. To characterize the validity of the assay system, clinical samples from children with inflammatory bowel disease were collected and analyzed, and the results were verified using isolation methods. We conclude that molecular assays targeting the 16S rRNA gene provides an important tool for the rapid diagnosis of chronic and infectious diseases caused by Veillonella and also supports the isolation and identification of Veillonella for research purposes. KEY POINTS: • With suitable primer sets, the qPCR has a wider detection range than ddPCR. • ddPCR is suitable for the detection of low-abundance samples. • Methods successfully guided the isolation of Veillonella in clinical sample.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139085604","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-12-01Epub Date: 2024-01-04DOI: 10.1007/s00253-023-12878-6
Yue-Sheng Zhang, Jin-Song Gong, Jia-Yu Jiang, Zheng-Hong Xu, Jin-Song Shi
Hyaluronidases catalyze the degradation of hyaluronan (HA), which is finding rising applications in medicine, cosmetic, and food industries. Recombinant expression of hyaluronidases in microbial hosts has been given special attention as a sustainable way to substitute animal tissue-derived hyaluronidases. In this study, we focused on optimizing the secretion of hyaluronidase from Homo sapiens in Pichia pastoris by secretion pathway engineering. The recombinant hyaluronidase was first expressed under the control of a constitutive promoter PGCW14. Then, two endoplasmic reticulum-related secretory pathways were engineered to improve the secretion capability of the recombinant strain. Signal peptide optimization suggested redirecting the protein into co-translational translocation using the ost1-proα signal sequence improved the secretion level by 20%. Enhancing the co-translational translocation by overexpressing signal recognition particle components further enhanced the secretory capability by 48%. Then, activating the unfolded protein response by overexpressing a transcriptional factor ScHac1p led to a secreted hyaluronidase activity of 4.06 U/mL, which was 2.1-fold higher than the original strain. Finally, fed-batch fermentation elevated the production to 19.82 U/mL. The combined engineering strategy described here could be applied to enhance the secretion capability of other proteins in yeast hosts. KEY POINTS: • Improving protein secretion by enhancing co-translational translocation in P. pastoris was reported for the first time. • Overexpressing Hac1p homologous from different origins improved the rhPH-20 secretion. • A 4.9-fold increase in rhPH-20 secretion was achieved after fermentation optimization and fed-batch fermentation.
{"title":"Engineering protein translocation and unfolded protein response enhanced human PH-20 secretion in Pichia pastoris.","authors":"Yue-Sheng Zhang, Jin-Song Gong, Jia-Yu Jiang, Zheng-Hong Xu, Jin-Song Shi","doi":"10.1007/s00253-023-12878-6","DOIUrl":"10.1007/s00253-023-12878-6","url":null,"abstract":"<p><p>Hyaluronidases catalyze the degradation of hyaluronan (HA), which is finding rising applications in medicine, cosmetic, and food industries. Recombinant expression of hyaluronidases in microbial hosts has been given special attention as a sustainable way to substitute animal tissue-derived hyaluronidases. In this study, we focused on optimizing the secretion of hyaluronidase from Homo sapiens in Pichia pastoris by secretion pathway engineering. The recombinant hyaluronidase was first expressed under the control of a constitutive promoter P<sub>GCW14</sub>. Then, two endoplasmic reticulum-related secretory pathways were engineered to improve the secretion capability of the recombinant strain. Signal peptide optimization suggested redirecting the protein into co-translational translocation using the ost1-proα signal sequence improved the secretion level by 20%. Enhancing the co-translational translocation by overexpressing signal recognition particle components further enhanced the secretory capability by 48%. Then, activating the unfolded protein response by overexpressing a transcriptional factor ScHac1p led to a secreted hyaluronidase activity of 4.06 U/mL, which was 2.1-fold higher than the original strain. Finally, fed-batch fermentation elevated the production to 19.82 U/mL. The combined engineering strategy described here could be applied to enhance the secretion capability of other proteins in yeast hosts. KEY POINTS: • Improving protein secretion by enhancing co-translational translocation in P. pastoris was reported for the first time. • Overexpressing Hac1p homologous from different origins improved the rhPH-20 secretion. • A 4.9-fold increase in rhPH-20 secretion was achieved after fermentation optimization and fed-batch fermentation.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139085606","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Folic acid deficiency is common worldwide and is linked to an imbalance in gut microbiota. However, based on model animals used to study the utilization of folic acid by gut microbes, there are challenges of reproducibility and individual differences. In this study, an in vitro fecal slurry culture model of folic acid deficiency was established to investigate the effects of supplementation with 5-methyltetrahydrofolate (MTHF) and non-reduced folic acid (FA) on the modulation of gut microbiota. 16S rRNA sequencing results revealed that both FA (29.7%) and MTHF (27.9%) supplementation significantly reduced the relative abundance of Bacteroidetes compared with control case (34.3%). MTHF supplementation significantly improved the relative abundance of Firmicutes by 4.49%. Notably, compared with the control case, FA and MTHF supplementation promoted an increase in fecal levels of Lactobacillus, Bifidobacterium, and Pediococcus. Short-chain fatty acid (SCFA) analysis showed that folic acid supplementation decreased acetate levels and increased fermentative production of isobutyric acid. The in vitro fecal slurry culture model developed in this study can be utilized as a model of folic acid deficiency in humans to study the gut microbiota and demonstrate that exogenous folic acid affects the composition of the gut microbiota and the level of SCFAs. KEY POINTS: • Establishment of folic acid deficiency in an in vitro culture model. • Folic acid supplementation regulates intestinal microbes and SCFAs. • Connections between microbes and SCFAs after adding folic acid are built.
{"title":"Role of folic acid in regulating gut microbiota and short-chain fatty acids based on an in vitro fermentation model.","authors":"Xiaogu Zheng, Chenlan Xia, Manman Liu, Hongchen Wu, Jiaqian Yan, Zihao Zhang, Yingjie Huang, Qing Gu, Ping Li","doi":"10.1007/s00253-023-12825-5","DOIUrl":"10.1007/s00253-023-12825-5","url":null,"abstract":"<p><p>Folic acid deficiency is common worldwide and is linked to an imbalance in gut microbiota. However, based on model animals used to study the utilization of folic acid by gut microbes, there are challenges of reproducibility and individual differences. In this study, an in vitro fecal slurry culture model of folic acid deficiency was established to investigate the effects of supplementation with 5-methyltetrahydrofolate (MTHF) and non-reduced folic acid (FA) on the modulation of gut microbiota. 16S rRNA sequencing results revealed that both FA (29.7%) and MTHF (27.9%) supplementation significantly reduced the relative abundance of Bacteroidetes compared with control case (34.3%). MTHF supplementation significantly improved the relative abundance of Firmicutes by 4.49%. Notably, compared with the control case, FA and MTHF supplementation promoted an increase in fecal levels of Lactobacillus, Bifidobacterium, and Pediococcus. Short-chain fatty acid (SCFA) analysis showed that folic acid supplementation decreased acetate levels and increased fermentative production of isobutyric acid. The in vitro fecal slurry culture model developed in this study can be utilized as a model of folic acid deficiency in humans to study the gut microbiota and demonstrate that exogenous folic acid affects the composition of the gut microbiota and the level of SCFAs. KEY POINTS: • Establishment of folic acid deficiency in an in vitro culture model. • Folic acid supplementation regulates intestinal microbes and SCFAs. • Connections between microbes and SCFAs after adding folic acid are built.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139085674","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Aspergillus oryzae PrtR is an ortholog of the transcription factor PrtT, which positively regulates the transcription of extracellular peptidase genes in Aspergillus niger and Aspergillus fumigatus. To identify the genes under the control of PrtR and elucidate its regulatory mechanism in A. oryzae, prtR gene disruption mutants were generated. The control strain clearly showed a halo on media containing skim milk as the nitrogen source, whereas the ΔprtR strain formed a smaller halo. Measurement of acid peptidase activity revealed that approximately 84% of acidic endopeptidase and 86% of carboxypeptidase activities are positively regulated by PrtR. As the transcription of the prtR gene varied depending on culture conditions, especially with or without a protein substrate, it was considered that its transcription would be regulated in response to a nitrogen source. In addition, contrary to previous expectations, PrtR was found to act both in promoting and repressing the transcription of extracellular peptidase genes. The mode of regulation varied from gene to gene. Some genes were regulated in the same manner in both liquid and solid cultures, whereas others were regulated in different ways depending on the culture conditions. Furthermore, PrtR has been suggested to regulate the transcription of peptidase genes that are closely associated with other transcription factors. KEY POINTS: • Almost all peptidase genes in Aspergillus oryzae are positively regulated by PrtR • However, several genes are regulated negatively by PrtR • PrtR optimizes transcription of peptidase genes in response to culture conditions.
{"title":"Aspergillus oryzae PrtR alters transcription of individual peptidase genes in response to the growth environment.","authors":"Rika Numazawa, Yukako Tanaka, Sawako Nishioka, Ryotaro Tsuji, Hiroshi Maeda, Mizuki Tanaka, Michio Takeuchi, Youhei Yamagata","doi":"10.1007/s00253-023-12833-5","DOIUrl":"10.1007/s00253-023-12833-5","url":null,"abstract":"<p><p>Aspergillus oryzae PrtR is an ortholog of the transcription factor PrtT, which positively regulates the transcription of extracellular peptidase genes in Aspergillus niger and Aspergillus fumigatus. To identify the genes under the control of PrtR and elucidate its regulatory mechanism in A. oryzae, prtR gene disruption mutants were generated. The control strain clearly showed a halo on media containing skim milk as the nitrogen source, whereas the ΔprtR strain formed a smaller halo. Measurement of acid peptidase activity revealed that approximately 84% of acidic endopeptidase and 86% of carboxypeptidase activities are positively regulated by PrtR. As the transcription of the prtR gene varied depending on culture conditions, especially with or without a protein substrate, it was considered that its transcription would be regulated in response to a nitrogen source. In addition, contrary to previous expectations, PrtR was found to act both in promoting and repressing the transcription of extracellular peptidase genes. The mode of regulation varied from gene to gene. Some genes were regulated in the same manner in both liquid and solid cultures, whereas others were regulated in different ways depending on the culture conditions. Furthermore, PrtR has been suggested to regulate the transcription of peptidase genes that are closely associated with other transcription factors. KEY POINTS: • Almost all peptidase genes in Aspergillus oryzae are positively regulated by PrtR • However, several genes are regulated negatively by PrtR • PrtR optimizes transcription of peptidase genes in response to culture conditions.</p>","PeriodicalId":8342,"journal":{"name":"Applied Microbiology and Biotechnology","volume":null,"pages":null},"PeriodicalIF":5.0,"publicationDate":"2024-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10781853/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139416180","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}