Cell for preparing competent cell, method for preparing competent cell and bacterial strain of Escherichia coli

摘要

The invention provides a cell for preparing competent cells, wherein the cell is capable of spontaneously accumulating self-producing trehalose therein and the cell is used for the preparation of competent cells. The invention also provides a method for preparing competent cells, including: culturing the cell for preparing the competent cell mentioned previously to obtain a cell suspension; placing the cell suspension into an ice bath; centrifuging the cell suspension to obtain a cell precipitate; mixing a transform reagent with the cell precipitate; and obtaining competent cells suspension.