Crystal structure of the hydroxyquinol 1,2-dioxygenase from Nocardioides simplex 3E, a key enzyme involved in polychlorinated aromatics biodegradation.

Hydroxyquinol 1,2-dioxygenase (1,2-HQD) catalyzes the ring cleavage of hydroxyquinol (1,2,4-trihydroxybenzene), a central intermediate in the degradation of aromatic compounds including a variety of particularly recalcitrant polychloro- and nitroaromatic pollutants. We report here the primary sequence determination and the analysis of the crystal structure of the 1,2-HQD from Nocardioides simplex 3E solved at 1.75 A resolution using the multiple wavelength anomalous dispersion of the two catalytic irons (1 Fe/293 amino acids).

Two unusual chlorocatechol catabolic gene clusters in Sphingomonas sp. TFD44.

The genes responsible for the degradation of 2,4-dichlorophenoxyacetate (2,4-D) by alpha-Proteobacteria have previously been difficult to detect by using gene probes or polymerase chain reaction (PCR) primers. PCR products of the chlorocatechol 1,2-dioxygenase gene, tfdC, now allowed cloning of two chlorocatechol gene clusters from the Sphingomonas sp. strain TFD44.

Characterization of a gene cluster encoding the maleylacetate reductase from Ralstonia eutropha 335T, an enzyme recruited for growth with 4-fluorobenzoate.

A gene cluster containing a gene for maleylacetate reductase (EC 1.3.1.

A new modified ortho cleavage pathway of 3-chlorocatechol degradation by Rhodococcus opacus 1CP: genetic and biochemical evidence.

The 4-chloro- and 2,4-dichlorophenol-degrading strain Rhodococcus opacus 1CP has previously been shown to acquire, during prolonged adaptation, the ability to mineralize 2-chlorophenol. In addition, homogeneous chlorocatechol 1,2-dioxygenase from 2-chlorophenol-grown biomass has shown relatively high activity towards 3-chlorocatechol. Based on sequences of the N terminus and tryptic peptides of this enzyme, degenerate PCR primers were now designed and used for cloning of the respective gene from genomic DNA of strain 1CP.