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The pyridoxal-binding site in pyridoxamine-pyruvate transaminase.

ABSTRACT: The enzyme-substrate complex formed between pyridoxamine-pyruvate transaminase (EC 2.6.1.30) and pyridoxal was reduced with NaBH4. After carboxymethylation and tryptic digestion, pyridoxyl-lysine-containing peptides were isolated by a combination of Sephadex and Dowex 50 chromatography. Analysis of these peptides shows the structure around the pyridoxal-binding lysine residues to be Ala-Asp-Ile-Tyr-Val-Thr-Gly-Pro-Asx-Lys(Pxy)-Cys-Leu(Pro2, Gly2, Ala2, Met)(Thr, Leu2)Gly-Val-Ser-Glu-Arg. This structure differs from those found for the corresponding peptides from pyridoxal phosphate-dependent enzymes.

SUBMITTER: Hodsdon J

PROVIDER: S-EPMC1184184 | biostudies-other | 1978 Feb

REPOSITORIES: biostudies-other

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