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Trapping and structural characterisation of a covalent intermediate in vitamin B₆ biosynthesis catalysed by the Pdx1 PLP synthase.

ABSTRACT: The Pdx1 enzyme catalyses condensation of two carbohydrates and ammonia to form pyridoxal 5-phosphate (PLP) via an imine relay mechanism of carbonyl intermediates. The I₃₃₃ intermediate characterised here using structural, UV-vis absorption spectroscopy and mass spectrometry analyses rationalises stereoselective deprotonation and subsequent substrate assisted phosphate elimination, central to PLP biosynthesis.

SUBMITTER: Rodrigues MJ

PROVIDER: S-EPMC8827014 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature

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Trapping and structural characterisation of a covalent intermediate in vitamin B6 biosynthesis catalysed by the Pdx1 PLP synthase.

Rodrigues Matthew J MJ Giri Nitai N Royant Antoine A Zhang Yang Y Bolton Rachel R Evans Gwyndaf G Ealick Steve E SE Begley Tadhg T Tews Ivo I

RSC chemical biology 20211025 2

The Pdx1 enzyme catalyses condensation of two carbohydrates and ammonia to form pyridoxal 5-phosphate (PLP) via an imine relay mechanism of carbonyl intermediates. The I333 intermediate characterised here using structural, UV-vis absorption spectroscopy and mass spectrometry analyses rationalises stereoselective deprotonation and subsequent substrate assisted phosphate elimination, central to PLP biosynthesis. ...[more]

PMID: 35360887

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