title: Biocatalytic Properties and Structural Analysis of Phloroglucinol Reductases.
abstract: Phloroglucinol reductases (PGRs) are involved in anaerobic degradation in bacteria, in which they catalyze the dearomatization of phloroglucinol into dihydrophloroglucinol. We identified three PGRs, from different bacterial species, that are members of the family of NAD(P)H-dependent short-chain dehydrogenases/reductases (SDRs). In addition to catalyzing the reduction of the physiological substrate, the three enzymes exhibit activity towards 2,4,6-trihydroxybenzaldehyde, 2,4,6-trihydroxyacetophenone, and methyl 2,4,6-trihydroxybenzoate. Structural elucidation of PGRcl and comparison to known SDRs revealed a high degree of conservation. Several amino acid positions were identified as being conserved within the PGR subfamily and might be involved in substrate differentiation. The results enable the enzymatic dearomatization of monoaromatic phenol derivatives and provide insight into the functional diversity that may be found in families of enzymes displaying a high degree of structural homology.
authors.affiliation: Institut für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany.
authors.forename: David
authors.identifier: 0000-0001-8984-7694
authors.initials: D
authors.lastname: Conradt
authors.affiliation: Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany.
authors.forename: Bianca
authors.initials: B
authors.lastname: Hermann
authors.affiliation: Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany.
authors.forename: Stefan
authors.identifier: 0000-0002-9098-8475
authors.initials: S
authors.lastname: Gerhardt
authors.affiliation: Institut für Biochemie, Albert-Ludwigs-Universität Freiburg, Albertstrasse 21, 79104, Freiburg, Germany.
authors.forename: Oliver
authors.initials: O
authors.lastname: Einsle
authors.affiliation: Institut für Pharmazeutische Wissenschaften, Albert-Ludwigs-Universität Freiburg, Albertstrasse 25, 79104, Freiburg, Germany.
authors.forename: Michael
authors.identifier: 0000-0002-2742-4992
authors.initials: M
authors.lastname: Müller
mesh_terms: D000098:Acetophenones / Q000378:metabolism; D001419:Bacteria / Q000737:chemistry / Q000201:enzymology* / Q000378:metabolism; D001547:Benzaldehydes / Q000378:metabolism; D055162:Biocatalysis; D005707:Gallic Acid / Q000031:analogs & derivatives / Q000378:metabolism; D044925:Oxidoreductases Acting on CH-CH Group Donors / Q000737:chemistry* / Q000378:metabolism*; D011487:Protein Conformation; D013379:Substrate Specificity
chemical_list: D000098:Acetophenones; D001547:Benzaldehydes; C052082:methyl gallate; D005707:Gallic Acid; C107067:2,4,6-trihydroxyacetophenone; D044925:Oxidoreductases Acting on CH-CH Group Donors; C058829:phloroglucinol reductase; C535196:2,4,6-trihydroxybenzaldehyde
keywords: dearomatization; enzyme catalysis; flavonoids; redox enzymes; reductases