Gromacs Turn off atoms

Dear all,
If I have a protein chain of consisting of:
AAARAAA or AAAAAAAR and want to prevent the argenine from interacting with anything (i.e. be invisible), how can I do so?

In the .itp file, can I just set the mass and charge of the arginine atoms to 0? Would that work? Does this also override non-bonded interaction parameters in the forcefield? I want to make the argenine completely invisible.

Thanks