The remains of many men who perished of disease in the camps around Knoxville are buried in Bethel Confederate Cemetery, Knoxville, TN in a common grave marked. The site is marked by an obelisk with a placard listing the men's names by state.

I believe this is the Nathan Nichols you seek:

Nichols N. F. 40-C 1862.06.05 Knoxville, TN (Bethel) is among those listed on that marker.