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What is Guanidine special group is presesnt in and explain in detail?
AMINO ACID SPECIAL GROUP Arginine Guanidinium Proline Pyrolidine Tryptophan Indole Phenylalanine Benzene Tyrosine Phenol Histidine Imidazole Methionine Thioether linkage Reference: Harpers illustrated biochemistry 30th edition