6B1B

STRUCTURE OF 4-HYDROXYPHENYLACETATE 3-MONOOXYGENASE (HPAB), OXYGENASE COMPONENT FROM ESCHERICHIA COLI MUTANT XS6 (APO Enzyme)

Summary for 6B1B

• Entry DOI: 10.2210/pdb6b1b/pdb
• Related: 5UM5
• Descriptor: 4-hydroxyphenylacetate 3-monooxygenase, oxygenase subunit, trimethylamine oxide (3 entities in total)
• Functional Keywords: protein engineering: 4-hydroxyphenylacetate 3-monooxygenase, oxygenase component, oxidoreductase active site loop mutant 7.2, oxidoreductase
• Biological source: Escherichia coli (strain B / BL21-DE3)
• Total number of polymer chains: 2
• Total formula weight: 120137.58

Authors

Zhou, D.,Kandavelu, P.,Wang, B.C.,Yan, Y.,Rose, J.P. (deposition date: 2017-09-18, release date: 2019-05-22, Last modification date: 2023-10-04)

Primary citation

Shen, X.,Zhou, D.,Lin, Y.,Wang, J.,Gao, S.,Kandavelu, P.,Zhang, H.,Zhang, R.,Wang, B.C.,Rose, J.,Yuan, Q.,Yan, Y.
Structural Insights into Catalytic Versatility of the Flavin-dependent Hydroxylase (HpaB) from Escherichia coli.
Sci Rep, 9:7087-7087, 2019

PubMed Abstract: 4-Hydroxyphenylacetate 3-hydroxylase (EcHpaB) from Escherichia coli is capable of efficient ortho-hydroxylation of a wide range of phenolic compounds and demonstrates great potential for broad chemoenzymatic applications. To understand the structural and mechanistic basis of its catalytic versatility, we elucidated the crystal structure of EcHpaB by X-ray crystallography, which revealed a unique loop structure covering the active site. We further performed mutagenesis studies of this loop to probe its role in substrate specificity and catalytic activity. Our results not only showed the loop has great plasticity and strong tolerance towards extensive mutagenesis, but also suggested a flexible loop that enables the entrance and stable binding of substrates into the active site is the key factor to the enzyme catalytic versatility. These findings lay the groundwork for editing the loop sequence and structure for generation of EcHpaB mutants with improved performance for broader laboratory and industrial use.

PubMed: 31068633
DOI: 10.1038/s41598-019-43577-w

Experimental method

X-RAY DIFFRACTION (1.944 Å)