1. First, put a proper amount of dry yeast powder into 37-degree water and stir it with chopsticks until it is completely dissolved.

2. Then add flour and stir it, and stir it with chopsticks until it becomes a block.

Rub the dough by hand, and then apply a little water on the surface to prevent it from drying. Cover it with a wet cloth and keep it in a warm place. When the volume becomes larger and there are many small bubbles on the surface, it can be done.

4. Add a little flour, knead the dough until the surface is smooth, and then cut the dough to make steamed bread.

Finally, put the prepared spaghetti in a steamer for half an hour, and then steam it.

Basic information

Yeast is a commonly used eukaryotic receptor cell in gene cloning experiments, and it is as convenient to culture yeast as Escherichia coli. There are many kinds of yeast cloning vectors.

Yeast also has plasmids. This 2μm long plasmid is called 2μm plasmid, which is about 6 300bp. This plasmid exists outside the chromosome in the nucleus for at least a period of time, and a shuttle plasmid that can shuttle between bacteria and yeast cells can be constructed by using 2μm plasmid and plasmid in Escherichia coli. Yeast cloning vectors are all constructed on this basis.