As early as 3000 BC, humans began to use yeast to make fermented products. The first product sold on the market was yeast paste, which is characterized by fast fermentation speed, but inconvenient transportation and use, and the commercialization of the product is subject to certain restrictions. Counting from the sale of yeast puree, the yeast industry has been developed for more than 200 years. Yeast has become one of the most studied microorganisms in the world. It is a hot spot in the research and development of biotechnology products and a model system for modern biotechnology development and genome research.
In 2012, the global yeast production capacity (calculated as dry yeast) exceeded 1 million tons, and the annual sales revenue exceeded 2.5 billion US dollars.
Since the 1980s, China's yeast industry has achieved leapfrog development, with independent innovative brands that sell well all over the world, and the research, production and application of yeast products have reached the international advanced level.
Determination of the upper limit of gene replication: Researchers from Okayama University in Japan and Tohoku University in Japan used an original method to determine the upper limit of the number of replications of all genes in yeast, and found that even if most genes are replicated more than 100 times, cells can still maintain normal functions, while some Gene copying only a few times will cause cell death.
The research team used yeast with about 6,000 genes to conduct experiments to investigate the upper limit of the number of replications of all its genes, that is, to what extent the number of gene replications will cause cell death. It was found that after more than 80% of the genes were replicated more than 100 times, the yeast cells still maintained normal functions. However, there are 115 genes that only replicate several times and cause the yeast to die. Most of these genes are related to basic functions such as intracellular transportation and cytoskeleton, and some genes are related to the production of intracellular proteins or protein complexes. The research team believes that these genes are duplicated several times, leading to unnecessary synthesis or decomposition of a large amount of protein, burdening the cells, causing serious disturbances in the balance of the yeast, resulting in the death of the yeast.