6E13

Pseudomonas putida PqqB with a non-physiological zinc at the active site binds the substrate mimic, 5-cysteinyl-3,4-dihydroxyphenylalanine (5-Cys-DOPA), non-specifically but supports the proposed function of the enzyme in pyrroloquinoline quinone biosynthesis.

Summary for 6E13

• Entry DOI: 10.2210/pdb6e13/pdb
• Descriptor: Coenzyme PQQ synthesis protein B, ZINC ION, CHLORIDE ION, ... (5 entities in total)
• Functional Keywords: iron-dependent, hydroxylase, metallo beta-lactamase, oxidoreductase
• Biological source: Pseudomonas putida (strain ATCC 47054 / DSM 6125 / NCIMB 11950 / KT2440)
• Total number of polymer chains: 1
• Total formula weight: 34482.14

Authors

Evans III, R.L.,Wilmot, C.M. (deposition date: 2018-07-09, release date: 2019-05-22, Last modification date: 2024-03-13)

Primary citation

Koehn, E.M.,Latham, J.A.,Armand, T.,Evans 3rd, R.L.,Tu, X.,Wilmot, C.M.,Iavarone, A.T.,Klinman, J.P.
Discovery of Hydroxylase Activity for PqqB Provides a Missing Link in the Pyrroloquinoline Quinone Biosynthetic Pathway.
J.Am.Chem.Soc., 141:4398-4405, 2019

PubMed Abstract: Understanding the biosynthesis of cofactors is fundamental to the life sciences, yet to date a few important pathways remain unresolved. One example is the redox cofactor pyrroloquinoline quinone (PQQ), which is critical for C1 metabolism in many microorganisms, a disproportionate number of which are opportunistic human pathogens. While the initial and final steps of PQQ biosynthesis, involving PqqD/E and PqqC, have been elucidated, the precise nature and order of the remaining transformations in the pathway are unknown. Here we show evidence that the remaining essential biosynthetic enzyme PqqB is an iron-dependent hydroxylase catalyzing oxygen-insertion reactions that are proposed to produce the quinone moiety of the mature PQQ cofactor. The demonstrated reactions of PqqB are unprecedented within the metallo β-lactamase protein family and expand the catalytic repertoire of nonheme iron hydroxylases. These new findings also generate a nearly complete description of the PQQ biosynthetic pathway.

PubMed: 30811189
DOI: 10.1021/jacs.8b13453

Experimental method

X-RAY DIFFRACTION (2.349 Å)