Human productive activities and normal life are closely related to microbes, and biofilm presents the prevalent mode of microbial growth in natural, engineered and medical settings. The existence of biofilm has both advantages and disadvantages for human beings. If the formation and degradation of biofilm can be controlled artificially, it will bring great benefits to human production and life. Numerous studies have shown that the formation and degradation of biofilms are controlled by cyclic diguanylate (c-di-GMP) in a wide range of bacteria. By talking with Prof. Zeng from the Institute of Hydrobiology, we knew that they urgently need an effective c-di-GMP measurement tool for their research at present. Through the interviews with experts from Biopharmaceutical Enterprises, we knew that there is still a lack of a high-throughput screening tool for c-di-GMP targeted drugs. These all spirited us to build a biosensor that can monitor the intracellular c-di-GMP concentration in a certain cell in real time using synthetic biology approaches, which could provide a powerful method for biofilm research. While we conduct a series of work, we also keep in touch with experts and constitutively improve our constructions to adapt to actual production and research. As iGEMers, we are happy to share, communicate and collaborate with researchers, and are committed to introducing synthetic biology to the public.
Prof. Xiaoli Zeng's team, from the Institute of Hydrobiology, Chinese Academy of Sciences, has been doing research on the function of c-di-GMP in Cyanobacteria for many years. In order to have a better understanding of the regulatory role of c-di-GMP in microorganisms, we visited the Institute of Hydrobiology and had a wonderful talk with the Prof. Zeng.
Prof. Zeng told us that c-di-GMP plays a very important role in the growth and survival of many bacteria. C-di-GMP has different functions in different strains of Cyanobacteria. During their study, it is crucial to monitor the intracellular c-di-GMP concentration of Cyanobacteria in real-time. Currently, they detect intracellular c-di-GMP concentration by High-Performance Liquid Chromatography. The sample preparation includes cell lysis, c-di-GMP extraction and sample concentration, which is time-cost; and it was found that c-di-GMP could dynamically change during the sample preparation due to the activities of its synthases and hydrolases. Moreover, such a method cannot achieve real-time c-di-GMP monitoring. There is no effective method for real-time monitoring of intracellular c-di-GMP concentration. The problems they are facing with c-di-GMP measurement inspired us to develop a new approach to easily detect the intracellular c-di-GMP level in real-time.
When we tested our biosensor, we found that the fluorescence was disproportionate to the concentration of c-di-GMP, and our biosensor showed a narrow dynamical range. To overcome these limits, Prof. Zeng suggested considering the avidity of transcription factor FleQ with c-di-GMP. If possible, it should be more desirable that creating FleQ mutants with different avidity of c-di-GMP could be selected for biosensor construction according to the native c-di-GMP concentration in a certain cell.
In order to understand the product development and application of synthetic biology, we contacted Dr. Ke, the expert of CATUG Biotechnology, who has rich experience in the entire industry chain from product development, quality research, clinical application to industrialization of biotechnologies.
First of all, Dr. Ke showed us around their pretreatment laboratory, QC laboratory and analytical technology development laboratory. In contrast to universities' laboratory, each laboratory in the enterprise has a clear function. These laboratories are mainly in the form of production line, which can achieve higher throughput analysis and continuous output of raw materials, enormously save time and labor costs.
Next, Dr. Ke introduced relevant information of their company, as well as the whole process of drugs from scientific research achievements to product launch. Drug research and development is divided into three stages. The first stage is drug discovery and pre-clinical stage, including target screening, proof of concept, CMC research and pharmacological and toxicological research. It is a long-term process, which consumes a lot of time and money. In China, most of the drug discovery and preliminary toxicological research are completed by universities and institutes. The second stage is clinical trial, which is divided into three phases to verify drug safety, effectiveness and measurement control. The third stage is the NMPA review, mass production and product launch.
Finally, we inquired into the market demand and prospect of synthetic biological products with Dr. Ke. He said that synthetic biology is mainly applied to development of basic industrial products, such as pollution reduction, green synthesis, and midstream products in pharmaceutical industry. At present, the scientific research achievements of synthetic biology in China still remain more in the laboratory stage, and have not yet achieved large-scale industrialization. He also said it is still a very emerging field with infinite potential. But it is believed that with the continuous development and maturity of synthetic biology, especially the rise of creative and practical competitions in the field of synthetic biology like iGEM, synthetic biology will continue to influence human life, which will bring great benefits to the world.
