Do you predict that bacterial transformation efficiency will

Do you predict that bacterial transformation efficiency will increase or decrease if you forget to add CaCl2 to the cells? In one complete sentence, explain your choice.

I was thinking decrease but idk why

Solution

It was discovered that treatment with Ca⁺⁺ at 4^oC of E. coli cells, washed with Mg ions, makes the bacteria competentt for transformation. Transformation of Ca-treated E.coli paved way for introduciton of foreign genes on plasmid vehicles. The Ca-treated cells are given a short exposure to a higher temperature (37-40^oC) before they are incubated, with shaking, at the proper temperature for growth (37^oC for E.coli). The reason behind the use of Ca in production of competent cells is that at near freezing temperatures Ca ions cause shrinkage of phospholipid molecules, exposing gaps in the cell membrane through which DNA molecules enter freely.