Why do enzymes only work in such a very narrow temperature range? Why does a tiny increase in temperature (fever) cause trouble for invading microorganisms?

Question

The Kelvin scale of temperature is linear. That means a material at 300 K has twice the energy than at 150 K.

The human body temperature is around 310 K. If you search for “human enzymes temperature range” you see images that show that enzymes work best in the 25º C to 45º C range, or 298 K to 318 K.

I know that if the temperature in too high the protein that makes the enzyme denatures and, if it’s too low, the molecules don’t colide as often with the enzymes and they don’t catalize as well. But why is such a small difference in temperature and energy capable of causing such huge changes in enzyme efficiency?

Why does a fever, an increase of less than 1% in body temperature (less than 3 K), cause such great difficulty to invading microorganisms?

In: 5

Answer 1

Enzymes/proteins are made up of tons of individual atoms that are bonded together. These bonds all have to work basically perfectly for the enzyme to function; think of what happens if a wheel comes loose in a running car, or the fuel pump cuts out.

It just so happens that these bonds all hold together at this narrow temperature range. If it’s too hot, bonds A, B, C start failing. Too cold, bonds D, E, F start failing. Either way, the enzymes starts to lose structure/functionality.