S. Harvey Mudd used duckweed as a model organism to study this amino acid’s biosynthesis. A derivative of this amino acid is converted into ACC and then oxidized into ethylene in (15[1])the Yang (15[1])cycle. Methyl sources used for DNA (15[1])methylation come (15[1])from adenosylated derivatives of this amino acid. Mutations in CBS or deficiencies in vitamin B6 contribute to a condition preventing the processing of this amino acid called homocystinuria. Unlike eukaryotes, bacteria are able to utilize a derivative of this amino acid containing an (*) N-formyl group. This amino acid and cysteine are the only proteinogenic sulfur-containing (10[1])amino (-5[1])acids. In the standard genetic code, this amino acid is encoded by the AUG codon. For 10 (10[1])points, what amino acid is often the first to be added to a (10[1])translating peptide? (10[1]0[3])■END■