High activity catechol 1,2-dioxygenase from Stenotrophomonas maltophilia strain KB2 as a useful tool in cis,cis-muconic acid production

Abstract

This is the first report of a catechol 1,2-dioxygenase from Stenotrophomonas maltophilia strain KB2 with high activity against catechol and its methyl derivatives. This enzyme was maximally active at pH 8.0 and 40 °C and the half-life of the enzyme at this temperature was 3 h. Kinetic studies showed that the value of Km and Vmax was 12.8 μM and 1,218.8 U/mg of protein, respectively. During our studies on kinetic properties of the catechol 1,2-dioxygenase we observed substrate inhibition at >80 μM. The nucleotide sequence of the gene encoding the S. maltophilia strain KB2 catechol 1,2-dioxygenase has high identity with other catA genes from members of the genus Pseudomonas. The deduced 314-residue sequence of the enzyme corresponds to a protein of molecular mass 34.5 kDa. This enzyme was inhibited by competitive inhibitors (phenol derivatives) only by ca. 30 %. High tolerance against condition changes is desirable in industrial processes. Our data suggest that this enzyme could be of use as a tool in production of cis,cis-muconic acid and its derivatives.

Genetic diversity of catechol 1,2-dioxygenase in the fecal microbial metagenome

“…The presence of a methylsubstituent in ortho ‐position to the hydroxyl group on the aromatic ring led to a significant decrease of the enzyme affinity for the corresponding phenol . CatPL12 did not reveal dependence of activity changes on position and kind of substituents as C12O from Stenotrophomonas maltophilia strain KB2 .…”

“…C12O activity was assayed spectrophotometrically by creating an assay mixture containing 50 µl of three times diluted C12O solution and 0.5 mM catechol as substrate. The final volume was adjusted to 3 ml with 50 mM Tris‐HCl buffer (pH 8.0).…”

“…Many C12O have been cloned and characterized from a variety of different bacteria, such as Acinetobacter , Arthrobacter , Corynebacterium , Pseudomonas , Rhodocococcus , Stenotrophomonas , and Streptomyces . Additionally, global microbial genome and environmental metagenome sequencing efforts are also contributing ever‐increasing genetic information to develop C12O.…”

Degradation of monoaromatics by Bacillus pumilus MVSV3

“…In our findings the SDS PAGE releaved a band at 35 kDa. Similarly the subunit molecular weight of C12D was estimated to be 31,558 and 34,500 Da from Rhodochrous NCIMB 13259 39 and Stenotrophomonas maltophilia strain KB2 40 , receptively. Three bands were observed in Zymography which were in agreement with the findings of three isoenzymes of C12D that have been reported from Pseudomonas arvilla C-1, which were formed by the combination of two nonidentical subunits 41 .…”

Genomic Analysis of Plant-Associated Bacteria and Their Potential in Enhancing Phytoremediation Efficiency

“…S. maltophilia strains are also able to promote growth of its plant host and to inhibit growth of phytopathogens through the production of chitinases, proteases, lysozyme, and secondary metabolites such as pyrrolnitrin, enterobactin and phenazine [Wu et al 2015;Zhang and Yuen 1999]. It has been reported that S. maltophilia strains are capable of degrading xenobiotics such as monocyclic aromatic hydrocarbons [Guzik et al 2013], drugs [Guzik et al 2009], and pesticides . Additionally, in many of S. maltophilia strains resistance to heavy metals was also observed [Ghosh and Das 2013] To effectively promote growth of its plant host, bacterium must possess certain traits that make it possible to penetrate plant avoiding response from the immune system and to establish colony in the internal tissues of plant.…”