???? ??? ??????? ???? ????? ???????? ??? ??? ?? ?? ???? ???? ?? ????? ???? ??? ???? ??? ??? ?? ??????? ??? ??? ??? ????? ??????? ????? ????? ???? ???, ?? ???? ??? ????? ????? ?????, ????? ??? ??? ????? ??????? ???. ??? ????? ???? ??? ?????? ??????? ???? ????? 20 ????? ??? ????? ??? ??? ?20 ??? ???? ??? ?? ??? ??? ??? ???? ??? ?1820 ?????? ???? ?? ????? ????? ?????? ?? ???? ??? ?? ? 1935 ???? ?? threonine ?????? ?? ????? ? ????? ??? ???? ??? ?? ???????? ???? ??? ???? ????? ????? ?????? ?? ?????? ????? ????. ???? ???? ??????? ???????? ???? ?????? ?? ??? ??? ?? ??? ???? ??? ???? ???? ?????? ???? ??????? ?? ???? ??????? ?????? ???? ??? ???? ??????? ?????? ?????? ?????? ??? ????? ????? ?????? ????? ?????? ??? ???? ??? ???? ??? ???? ???? ??????? ? 5 ???? ???? ????-????? ???? ? ????? (?????) (?????) (Gln) ? ???? (??) ?? ????? (???) ???? ????? ??? ???? ???? ?????? ?????? ????? ???? ??? ??? ??? ????? ????? ??? ?????? ???? ?????? (???)? ??????? (??)? ???? (???)? ????? (Thr)? ????? (??) ?? ?????? (??) ??????? ??? ???? ???? ??? ???? ?????? ??????? ??? ??? ??? ?????? ?????? ????? ??? ??? ?????? (Phe)? ????? (???) ?? ??????? (Trp)? ??? ?? ??? ???? ??? ???? ????? ????? ??? ???? ???? ? erythrosis-4-???? (E4P) ?? phosphoenolpyruvate (PEP) ??? ?????? ?????? ????? ??? ????? ??????? ???. ???? ???? ??? (??)? ???? (??) ?? ?????? (????) ??????? ??? ???? ???? ??? ???? ?????? ???? ??? ??? ????? ???????? ????? ?????? ??? ??? ????? ??? ???? (??), ??? (??) ?? ??? (?) ?????. ??? ???? ???? ??? ???? ????? ????? ????? ????, ??????? ?? ????? ??? ????, ?? ???? ???? ???? ?? ???? ???? ?????? ??????.

Isoleucine? Valine ?? Leucine ??? ???? ????? ????? ???? ?????? ????? ????? ????? ??? ????? ???? ?? ?????? ???? ??????? ???? ??? ??? ??? ??. ?????? ??? ??? ??? ??????? ? erythrosis-4-P ?? PEP ????? ?????? ??????? ?? ??, ?? ????? ??? ? phosphoribose pyrophosphate (PRPP) ???? ??. ? PRPP ???? ??? ??? ??? ??? ?? 5 ???? ??? imidazole ???? ?????? ??? ?? ???? ? ????? ??? ? 3C ??? ????? ????? ??????? ???? ???? ??????? ??????? ???? ??? ??? ?? ?????? ??? ???????? ???? ?? ?????? ?????? ????? ??? ?? ???? ??? ???? ???? ??? ?? ???? ???. ??? ????? ???????? ???? ???? ???? ?? ???? ?? ??? ??? ????? ????? ????? ????? ????? ????? ????? ??? ????? ?? ??? ???????? ??? ???

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