1. The most suitable fermentation temperature is 4-42℃.

2. The most suitable growth temperature is: 2℃~3℃.

if it exceeds 55°C, it is likely to cause yeast death.

Yeast is a kind of unicellular fungi, not a unit of phylogenetic classification. Ascomycetes, Basidiomycetes and other single-celled fungi are the general names, which can be used for brewing production, some are pathogenic bacteria, and are model organisms for genetic engineering and cell cycle research. Yeast is the earliest microorganism used in the history of human civilization. Can survive in an anoxic environment. At present, there are more than 1, kinds of yeasts. According to their ability to produce spores (ascospores and basidiomycetes), yeasts can be divided into three types: Ascomycetes, Basidiomycetes and Incomplete Fungi < P > Yeast is a commonly used eukaryotic receptor cell in gene cloning experiments, and it is as convenient to cultivate yeasts as Escherichia coli. There are many kinds of yeast cloning vectors. Yeast also has plasmids. This 2pm long plasmid is called 2um plasmid, which is about 6 3bp. This plasmid exists outside the chromosome in the nucleus for at least a period of time. Using the 2pm plasmid and the plasmid in E.coli, we can construct a shuttle plasmid that can shuttle between bacteria and yeast cells. Yeast cloning vectors are all constructed on this basis.