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Elimination, Replacement and Isomerization Reaotions by Intact Cells Containing Tyrosine Phenol Lyase

1972; Oxford University Press; Volume: 36; Issue: 11 Linguagem: Inglês

10.1271/bbb1961.36.1869

1881-1280

Hitoshi Enei, Hiroshi Matsui, Shinji Okumura, Hideaki Yamada,

Biopolymer Synthesis and Applications

Tyrosine phenol lyase catalyzes a series of α, β-elimination, β-replacement and racemization reactions. These reactions were studied with intact cells of Erwinia herbicola ATCC 21434 containing tyrosine phenol lyase. Various aromatic amino acids were synthesized from L-serine and phenol, pyrocatechol, resorcinol or pyrogallol by the replacement reaction using the intact cells. L (D)-Tyrosine, 3, 4-dihydroxyphenyl-L (D)-alanine (L (D)-dopa), L (D)-serine, L-cysteine, L-cystine and S-methyl-L-cysteine were degraded to pyruvate and ammonia by the elimination reaction. These amino acids could be used as substrate, together with phenol or pyrocatechol, to synthesize L-tyrosine or L-dopa via the replacement reaction by intact cells. L-Serine and D-serine were the best amino acid substrates for the synthesis of L-tyrosine or L-dopa. L-Tyrosine and L-dopa synthesized from D-serine and phenol or pyrocatechol were confirmed to be entirely L-form after isolation and identification of these products. The isomerization of D-tyrosine to L-tyrosine was also catalyzed by intact cells. Thus, L-tyrosine or L-dopa could be synthesized from DL-serine and phenol or pyrocatechol by intact cells of Erwinia herbicola containing tyrosine phenol lyase.