This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Proteins and Amino Acids, Subject name: Biochemistry
[{'content': "Edman's reagent is - \nSelect and explain. \nA. 2-4 dinitrophenol, B. 1 -fluoro-2, 4-dinitrobenzene, C. Phenyl-isocyanate, D. Cynogen bromide", 'role': 'user'}, {'content': "Answer: C \nExplanation: Ans. is 6c' i.e., Phenyl-isocyanateo Determination of amino acid sequence (sequence analysis) is performed by Edman degradation method on automatic mechines, called cyclic sequentors. Edman's reagent is phenyl-isothiocyanate, and forms a covalent bond to N- terminal of amino-acid. This can be identified.o Sanger's reagent (l-fluoro-2,4-dinitrobenzene) can be used in place of Edman's reagent.", 'role': 'assistant'}]