Disease relevance of xylT

• The xylT gene product, a component of the xylene catabolic pathway of Pseudomonas putida mt2, has been recently characterized as a novel [2Fe-2S] ferredoxin which specifically reactivates oxygen-inactivated catechol 2,3-dioxygenase (XylE) [1].
• Ferredoxins and ferredoxin reductases were also cloned from Streptomyces coelicolor and biocatalytic Streptomyces strains and tested in ema1 coexpression systems to optimize the electron transport towards Ema1 [2].
• The 6-kDa FD of E. histolytica and G. lamblia were most similar to those of the archaebacterium Methanosarcina barkeri and the delta-purple bacterium Desulfovibrio desulfuricans, respectively, while the 12-kDa FD of the T. vaginalis hydrogenosome was most similar to the 12-kDa FD of gamma-purple bacterium Pseudomonas putida [3].
• Four (CYP195A2, CYP199A2, CYP203A1, and CYP153A5) of the seven P450 enzymes, and palustrisredoxin A, a ferredoxin associated with CYP199A2, from the metabolically diverse bacterium Rhodopseudomonas palustris have been expressed and purified [4].

High impact information on xylT

• In the xylT mutants, all the meta-cleavage enzymes were induced by p-toluate with the exception of catechol 2,3-dioxygenase whose activity was 1% of the p-toluate-induced activity in wild-type cells [5].
• Addition of 4-methylcatechol to m-toluate-grown wild-type and xylT cells resulted in the inactivation of catechol 2,3-dioxygenase in these cells [5].
• We constructed pWW0 mutants defective in the xylT gene, and found that these mutants were not able to grow on p-toluate while they were still capable of growing on benzoate and m-toluate [5].
• In vivo reactivation of catechol 2,3-dioxygenase mediated by a chloroplast-type ferredoxin: a bacterial strategy to expand the substrate specificity of aromatic degradative pathways [5].
• Purified XylE is oxygen-sensitive and unstable in vitro, particularly in the presence of substituted catechol substrates, but it is stabilized in vivo by another protein, XylT, encoded by the xylT gene located just upstream of xylE [6].

Biological context of xylT

• The nahT gene, the homologue of xylT, present on NAH plasmid NAH7 encoding naphthalene-degrading enzymes, was also sequenced [7].
• The nucleotide sequence of xylT was determined in this study and putative gene product was shown to contain a sequence characteristic for chloroplast-type ferredoxins [7].

Associations of xylT with chemical compounds

• The putative regulatory gene, designated cdoR, is divergently transcribed from the ferredoxin and catechol dioxygenase genes, cdoT and cdoE, respectively [8].

References