7KQS

A 1.68-A resolution 3-fluoro-L-tyrosine bound crystal structure of heme-dependent tyrosine hydroxylase

Summary for 7KQS

• Entry DOI: 10.2210/pdb7kqs/pdb
• Descriptor: Heme-dependent L-tyrosine hydroxylase, PROTOPORPHYRIN IX CONTAINING FE, 2-AMINO-2-HYDROXYMETHYL-PROPANE-1,3-DIOL, ... (6 entities in total)
• Functional Keywords: heme-binding enzyme, l-tyrosine hydroxylase, oxidoreductase
• Biological source: Streptomyces sclerotialus
• Total number of polymer chains: 2
• Total formula weight: 71208.89

Authors

Wang, Y.,Liu, A. (deposition date: 2020-11-17, release date: 2021-03-31, Last modification date: 2023-10-18)

Primary citation

Wang, Y.,Davis, I.,Shin, I.,Xu, H.,Liu, A.
Molecular Rationale for Partitioning between C-H and C-F Bond Activation in Heme-Dependent Tyrosine Hydroxylase.
J.Am.Chem.Soc., 143:4680-4693, 2021

PubMed Abstract: The heme-dependent l-tyrosine hydroxylases (TyrHs) in natural product biosynthesis constitute a new enzyme family in contrast to the nonheme iron enzymes for DOPA production. A representative TyrH exhibits dual reactivity of C-H and C-F bond cleavage when challenged with 3-fluoro-l-tyrosine (3-F-Tyr) as a substrate. However, little is known about how the enzyme mediates two distinct reactions. Herein, a new TyrH from the thermophilic bacterium (SsTyrH) was functionally and structurally characterized. A crystal structure of the enzyme-substrate complex at 1.89-Å resolution provides the first comprehensive structural study of this hydroxylase. The binding conformation of l-tyrosine indicates that C-H bond hydroxylation is initiated by electron transfer. Mutagenesis studies confirmed that an active site histidine, His88, participates in catalysis. We also obtained a 1.68-Å resolution crystal structure in complex with the monofluorinated substrate, 3-F-Tyr, which shows one binding conformation but two orientations of the fluorine atom with a ratio of 7:3, revealing that the primary factor of product distribution is the substrate orientation. During reaction, a ferric-hydroperoxo intermediate (compound 0, Fe-OOH) was observed with 3-F-Tyr as a substrate based on characteristic spectroscopic features. We determined the crystal structure of this compound 0-type intermediate and refined it to 1.58-Å resolution. Collectively, this study provided the first molecular details of the heme-dependent TyrH and determined the primary factor that dictates the partitioning between the dual reactivities of C-H and C-F bond activation.

PubMed: 33734681
DOI: 10.1021/jacs.1c00175

Experimental method

X-RAY DIFFRACTION (1.677 Å)