Guanidine group is present in
Amino acid  
Special group








Histidine


Imidazole




Proline


Imino group / Pyrrolidine group




Tryptophan


Indole




ariginine


Guanidine group




Phenylalanine


Benzene ring




Tyrosine


Phenol.
Histidine
Proline
Tryptophan
Arginine