Biotechnology Notes最新文献

Synthetic biology has captivated scientists' imagination. It promises answers to some of the grand challenges society is facing: worsening climate crisis, insufficient food supplies for ever growing populations, and many persisting infectious and genetic diseases. While many challenges remain unaddressed, after almost two decades since its inception a number of products created by engineered biology are starting to reach the public. European scientists and entrepreneurs have been participating in delivering on the promises of synthetic biology. Associations like the European Synthetic Biology Society (EUSynBioS) play a key role in disseminating advances in the field, connecting like-minded people and promoting scientific development. In this perspective article, we review the current landscape of the synthetic biology community in Europe, discussing the state of related academic research and industry. We also discuss how EUSynBioS has helped to build bridges between professionals across the continent.

Resveratrol is a plant-derived aromatic compound with beneficial properties and it is required to develop a resveratrol production process from inexpensive biomass feedstocks. Here, we investigated the potential of Scheffersomyces stipitis, a non-conventional yeast with the capacity to utilize a wide range of sugars, to produce resveratrol from molasses, which is a by-product of sugar refineries. The S. stipitis strain metabolically engineered for resveratrol production produced resveratrol from 60 g/L mixed sugar (sucrose, glucose, and fructose), while its resveratrol titer decreased as the proportions of glucose and fructose increased. Sucrose consumption of the S. stipitis strain was clearly suppressed by the coexistence of glucose, fructose, and even ethanol. Quantitative analysis of intracellular metabolites involved in resveratrol biosynthesis using capillary electrophoresis time-of-flight mass spectrometry revealed that the composition of these sugars has a significant effect on the intracellular accumulation of glycolytic metabolites and AMP, which is an important factor involved in some cellular metabolic responses. Furthermore, the S. stipitis strain produced 1076 ± 167 mg/L of resveratrol in the fermentation with commercial sugarcane molasses (120 g/L of total sugars) as the substrate. To our knowledge, this is the first report on carbon catabolite repression in S. stipitis caused by the coexistence of sucrose, glucose, and fructose and resveratrol production from molasses. These results indicate great potential of the cost-effective resveratrol production process from molasses substrates using recombinant S. stipitis.

Fluorescent proteins are widely used molecular reporters in studying gene expression and subcellular protein localization. To enable the monitoring of transient cellular events in the model yeast Saccharomyces cerevisiae, destabilized green and cyan fluorescent proteins have been constructed. However, their co-utilization is limited by an overlap in their excitation and emission spectra. Although red fluorescent protein is compatible with both green and cyan fluorescent proteins with respect to spectra resolution, a destabilized red fluorescent protein is yet to be constructed for applications in S. cerevisiae. To realize this, we adopted a degron-fusion strategy to prompt destabilization of red fluorescent protein. Specifically, we fused two degrons derived from Cln2, a G₁-specific cyclin that mediates cell cycle transition, to the N- or C-terminus of mCherry to generate four destabilized fluorescent proteins that are soluble and functional in S. cerevisiae. Importantly, the four mCherry fluorescent proteins are highly differential with regards to fluorescence half-life and intensity, which provides a greater choice of tools available for the study of dynamic gene expression and transient cellular processes in the model yeast.

Given its highly innovative character and potential socioeconomic impact, Synthetic Biology is often ranked among prominent research areas and national research priorities in developed countries. The global evolution of this field is proceeding by leaps and bounds but its development at the level of individual states varies widely. Despite their current satisfactory economic status, the majority of 13, mostly post-communist, countries that entered the European Union family in and after 2004 (EU13) have long overlooked the blossoming of Synthetic Biology. Their prioritized lines of research have been directed elsewhere or “Synthetic Biology” did not become a widely accepted term to encompass their bioengineering and biotechnology domains. The Czech Republic is not an exception. The local SynBio mycelium already exists but is mainly built bottom-up through the activities of several academic labs, iGEM teams, and spin-off companies. In this article, we tell their individual stories and summarize the prerequisites that allowed their emergence in the Czech academic and business environment. In addition, we provide the reader with a brief overview of laboratories, research hubs, and companies that perform biotechnology and bioengineering-oriented research and that may be included in a notional “shadow SynBio community” but have not yet adopted Synthetic Biology as a unifying term for their ventures. We also map the current hindrances for a broader expansion of Synthetic Biology in the Czech Republic and suggest possible steps that should lead to the maturity of this fascinating research field in our country.

With more and more researchers conducting extensive research on all aspects of ribosomes, how to extract ribosomes with good effect and high activity has become a fundamental problem. In this article, Escherichia coli A19, MRE600, and JE28 cells often mentioned in the literature and ordinary E. coli BL21(DE3) cells were used to extract ribosomes by ultracentrifugation. The purpose was to study whether the ultracentrifugation method can be applied to extract effective ribosomes, and whether the ribosome extracts from different cells were different. The extracted ribosomes were validated by RNA electrophoresis, SDS-PAGE, PURE system, and mass spectrometry. The validation experiment results showed that ribosomes from these four cells had different effects. The success of the experiment confirmed that effective ribosomes could be extracted from E. coli by ultracentrifugation, which laid a good foundation for researchers to carry out further applications on ribosomes.

The 1st western China symposium on the international frontier of synthetic biomanufacturing was successfully held on July 8–10 in 2022. The conference is firstly launched by Professor Dan Wang in Chongqing University, and will be organized regularly every year by different universities in western China. The aim of this symposium is to show the cutting-edge knowledge of the synthetic biology developed in China and worldwide, provide a chance to meet international colleagues, and also to promote the academic and economic development of western China. Due to COVID-19, the 2022 symposium was masterfully delivered on the combination of online and offline operation, and the organisers must be commended for a really excellent and interactive meeting.

The content of the conference involves two modules of synthetic biology and green biomanufacturing, covering eight aspects: synthetic biology, metabolic engineering, biological process engineering, industrial microbial breeding, biocatalysis and biotransformation, synthetic bio-materials, bio-medicine and biological separation engineering. More than 400 representatives were invited to gather together to exchange the latest research results and development trends in the field of synthetic biology and biomanufacturing. There was a significant focus on the younger scientists, both in terms of oral reports and posters. There were many excellent invited lectures and sessions beyond the remit of this short summary, including “Pharmaceutical manufacturing by biological methods” by Yuguo Zheng, Academician of the Chinese Academy of Engineering (CAE) Member of China, and a lecture “The third generation of biological manufacturing: preparing chemicals with CO₂ as raw material” by Tianwei Tan, Academician of the CAE Member of China, a lecture on the biotransformation and green separation of natural products by Prof. Huizhou Liu, a lecture of the synthetic biology of Halophilic bacteria by Prof. Guoqiang Chen, a lecture of design principles to engineer yeasts as microbial factories by Ass. Prof. Zengyi Shao in Iowa State University, and a outstanding overview of the development of synthetic biology from basic research to industrialization in China to list just six.

In this article we will cover some pertinent areas of synthetic biology and biomanufacturing amidst the unavoidable spectra of COVID-19.

N-acetylglucosamine (GlcNAc), a glucosamine derivative, has a wide range of applications in pharmaceutical fields, and there is an increasing interest in the efficient production of GlcNAc genetic engineered bacteria. In this work, Escherichia coli ATCC 25947 (DE3) strain was engineered by a model-based dynamic regulation strategy achieving GlcNAc overproduction. First, the GlcNAc synthetic pathway was introduced into E. coli, and through flux balance analysis of the genome-scale metabolic network model, metabolic engineering strategies were generated to further increase GlcNAc yield. Knock-out of genes poxB and ldhA, encoding pyruvate oxidase and lactate dehydrogenase, increased GlcNAc titer by 5.1%. Furthermore, knocking out N-acetylmuramic acid 6-phosphate etherase encoded by murQ and enhancing glutamine synthetase encoded by glnA gene further increased GlcNAc titer to 130.8 g/L. Analysis of metabolic flux balance showed that GlcNAc production maximization requires the strict dynamic restriction of the reactions catalyzed by pfkA and zwf to balance cell growth and product synthesis. Hence, a dynamic regulatory system was constructed by combining the CRISPRi (clustered regularly interspaced short palindromic repeats interference) system with the lactose operon lacI and the transcription factor pdhR, allowing the cell to respond to the concentration of pyruvate and IPTG to dynamically repress pfkA and zwf transcription. Finally, the engineered bacteria with the dynamic regulatory system produced 143.8 g/L GlcNAc in a 30-L bioreactor in 55 h with a yield reaching 0.539 g/g glucose. Taken together, this work significantly enhanced the GlcNAc production of E. coli. Moreover, it provides a systematic, effective, and universal way to improve the synthetic ability of other engineered strains.

Regulatory mechanisms that direct the synthesis and release of pyocin S5, a surface-acting bacteriocin produced by Pseudomonas aeruginosa, are relatively unknown. This study aims to identify transcription factors that regulate pyocin S5 expression in P. aeruginosa PAO1. We captured the transcription factor MvaT using the promoter region upstream of S5 gene (S5P). Further, we demonstrated specific binding of MvaT and its paralog MvaU to S5P using a gel-shift assay. Lastly, we showed that MvaT negatively regulates the S5 gene expression by gene deletion and transcriptomic analysis. Our findings provide valuable insights into the regulation of pyocin S5 production, which paves the way to develop novel therapeutics against P. aeruginosa infections.

There is a global increase in cases of hyperuricemia over the last 10 years. A critical component of serum uric acid control is the transport of uric acid to the intestinal lumen, which accounts for 30% of the uric acid eliminated from the serum. This mini review looks at two important aspects of elevated uric acid: the dynamics of intestinal uric acid transport and hyperuricemia co-morbidities. Elevated serum uric acid can lead to gout and it can also impact other diseases such as diabetes, cardiovascular diseases and nervous system diseases. The level of uric acid in the intestine could be related to the potential for uric acid to impact other morbidities. We review the evidence for this and what it would mean for persons with elevated serum uric acid.

Due to inherent complexity, incompatibility, and variability in living cell systems, biomolecular engineering faces significant obstacles. To find novel solutions to these issues, researchers have turned to cell-free synthetic biology (CFSB), a relatively young field of study. Biochemical processes can be triggered in vitro through cell-free synthesis, providing a wider range of options for biomolecular engineering. Here, we provide a survey of recent advances in cell-free synthesis. These have sparked innovative studies in areas including the synthesis of complex proteins, incorporation of unnatural amino acids, precise post-translational modifications, high-throughput workflow, and synthetic biomolecular network regulation. CFSB has transformed the studies of biological machinery in a profound and practical way for versatile biomolecular engineering applications.