Source: CCTV news client
Yesterday (23rd), the reporter learned at a press conference held by the Chinese Academy of Sciences that after years of research and research, China has made major breakthroughs in the synthesis of starch, and for the first time in the world, the total synthesis from carbon dioxide to starch has been realized. Synthetic starch from carbon dioxide is considered by the international academic community to be a major disruptive technology that affects the world, and this achievement was published today (24th) in the international academic journal Science.
In crops such as corn, the synthesis and accumulation of starch by natural photosynthesis involves more than 60 steps of biochemical reactions and complex physiological regulation, and the theoretical energy conversion efficiency is about 2%. Through years of research, the scientific research team of the Tianjin Institute of Industrial Biology of the Chinese Academy of Sciences and the Dalian Institute of Chemicals have adopted a similar "building block" method to realize the energy transformation mode of "light energy-electric energy-chemical energy" by coupling chemical catalysis and biocatalytic module system, and successfully built an artificial pathway with only 11 steps of reaction from carbon dioxide to starch synthesis.
Cai Tao, associate researcher of Tianjin Institute of Industrial Biology, Chinese Academy of Sciences: Our research team has proposed a new idea of chemical and biological coupling catalytic synthesis of starch, and it only takes a few hours in the laboratory to complete the starch synthesis process that takes several months for crops.
The latest breakthrough of the scientific research team in starch synthesis not only has fewer steps, but also has higher energy conversion efficiency and synthesis speed. The theoretical energy conversion efficiency of this artificial pathway from solar energy to starch is 3.5 times that of corn, and the starch synthesis rate is 8.5 times that of corn. Under the condition of sufficient energy supply, according to the current technical parameters, the annual output of starch in the bioreactor with a theoretical size of 1 cubic meter is equivalent to the average annual yield of corn planting in 5 mu of land in China.
Ma Yanhe, director of the Tianjin Institute of Industrial Biology of the Chinese Academy of Sciences: Although it is still in the laboratory stage, there will be more scientific challenges in the future, but once the industry is realized, it will play a very important supporting role in our food security to the use of carbon dioxide and our goal of double carbon.
Chu Xiaoying, International and Academic Publishing Cooperation Director of Science Magazine: It is a major breakthrough in the field of synthetic starch, and it is also the first time in the world (in the laboratory) that the entire process of synthesizing starch from carbon dioxide is a major milestone breakthrough for the field of biosynthetic biomanufacturing, and then the next step is actually a new way for agricultural production and industrial biomanufacturing, which has a very significant significance.
Three core breakthroughs to achieve synthetic starch >>
Starch is the most important component of grain and an important industrial raw material. How is this disruptive technology of synthetic starch from carbon dioxide achieved? Where is the core breakthrough?
Highlight 1: Energy conversion efficiency increased by 3.5 times To break through the limitations of natural photosynthetic carbon sequestration system using solar energy
In order to design a carbon sequestration route that exceeds the natural ability, the scientific research team innovatively proposed a coupling scheme of chemical and biocatalysis, and constructed a carbon sequestration route with only 11 main reactions from about 7,000 biochemical reactions, which increased the theoretical energy conversion efficiency by 3.5 times, making it possible to efficiently fix carbon dioxide and efficiently synthesize starch.
Highlight 2: From more than 60 steps to 11 steps, break through the complex regulatory barriers of starch synthesis in nature
In computationally designed artificial pathways, biological enzyme catalysts are central to the successful construction of this pathway. The scientific research team excavated suitable biological enzyme catalysts from 31 different species sources such as animals, plants, and microorganisms, and constructed an artificial starch synthesis pathway with only 11 steps, which significantly reduced the complexity of synthesis compared with the more than 60 steps required for starch synthesis in nature.
Highlight 3: Break through the limitation of low efficiency of natural starch synthesis time and space
Due to the lack of evolutionary processes over the past hundreds of millions of years in the natural pathway, there is a problem that it is difficult to adapt between biological enzyme catalysts derived from different species in the artificial pathway. Aiming at this problem, the research team developed the module assembly optimization and spatiotemporal separation reaction strategy, which solved the problems of substrate competition and product inhibition in the artificial pathway, and finally obtained the artificial pathway with significant improvement in starch synthesis rate and efficiency.
Synthetic starch: The road to industrialization faces many challenges >>
Calculated from the parameters of carbon dioxide synthetic starch, the annual starch output of a bioreactor with a size of 1 cubic meter can be equivalent to the yield of 5 mu of corn starch. So what are the similarities and differences between synthetic starch and starch in nature? What are the challenges of industrialization of starch production? Let's listen to the experts' interpretations.
Ma Yanhe, director of the Tianjin Institute of Industrial Biology of the Chinese Academy of Sciences: The starch produced through this artificial route is mainly amylose, of course, now we can also add a branch enzyme, which can be made into amylopectin. Now we have a little sample in the lab, but we haven't applied it yet.
Cai Tao, associate researcher of Tianjin Institute of Industrial Biology, Chinese Academy of Sciences: The most important thing is that we pass our scientific gold standard, that is, nuclear magnetic testing, we take our synthetic amylose (starch) and branch chain (starch) and natural amyl chain (starch) and branch chain (starch) together to compare, the result of getting nuclear magnetism is exactly the same, so we can say that the starch we synthesize is actually no different from natural starch.
According to the scientific research team, although the path of synthetic starch has been opened, only a small number of starch samples have been produced in the laboratory, and there are still many challenges to truly realize the industrialization of synthetic starch.
Ma Yanhe, director of the Tianjin Institute of Industrial Biology of the Chinese Academy of Sciences: If it becomes industrialized, we say that with the concept of synthetic biology, we redesign the function of the organism and even the organism, and then let it break through the limitations of natural organisms, which can greatly shorten its production cycle and reduce its cost.
Zhou Qi, vice president of the Chinese Academy of Sciences and academician of the Chinese Academy of Sciences: This work is in line with the Chinese Academy of Sciences in the field of basic research, taking the major needs of society and the major problems facing mankind as our starting point, and the intersection of multiple disciplines and the integration of disciplines will be the model and way of future scientific and technological innovation.
(CCTV reporter Shuai Junquan Hao Liang)