This basically causes the proteins in the bacterial cells to basically denature and that decreases the activity and functionality of our enzymes found in bacterial cells. Now, let's move on to our acidity level. So how exactly does the PH or the concentration of hydrogen ions affects our functionality and activity of proteins of our enzyme? So the concentration of hydrogen ions, the PH, can also affect the activity of enzymes. For instance, the human body actually spends a lot of its energy in making sure that the PH of the blood as well as other systems, other fluids within our body, remains at a specific level. And at times it can basically change the PH of certain fluid areas within our body to basically activate or deactivate certain enzymes.