Identification of genes involved in the 4-aminobenzenesulfonate degradation pathway of hydrogenophaga sp PBC via transposon mutagenesis

• Main Authors: Han, Ming Gan, Ibrahim, Zaharah, Shahir, Shafinaz, Yahya, Adibah
• Format: Article
• Language: English
• Published: Blackwell Publishing 2011
• Subjects: Q Science; TP Chemical technology
• Online Access: http://eprints.utm.my/id/eprint/29132/1/HanMingGan2011_IdentificationofGenesInvolvedinthe4AminobenzenesulfonateDegradation.pdf; http://eprints.utm.my/id/eprint/29132/; http://dx.doi.org/10.1111/j.1574-6968.2011.02245.x

Genes involved in the 4-aminobenzenesulfonate (4-ABS) degradation pathway of Hydrogenophaga sp. PBC were identified using transposon mutagenesis. The screening of 10000 mutants for incomplete 4-ABS biotransformation identified four mutants with single transposon insertion. Genes with insertions that impaired the ability to utilize 4-ABS for growth included (1) 4-sulfocatechol 1,2-dioxygenase ß-subunit (pcaH2) and 3-sulfomuconate cycloisomerase involved in the modified ß-ketoadipate pathway; (2) 4-aminobenzenesulfonate 3,4-dioxygenase component (sadA) involved in aromatic ring hydroxylation; and (3) transposase gene homolog with a putative cis-diol dehydrogenase gene located downstream. The pcaH2 mutant strain accumulated brown metabolite during growth on 4-ABS which was identified as 4-sulfocatechol through thin layer chromatography and HPLC analyses. Supplementation of wild-type sadA gene in trans restored the 4-ABS degradation ability of the sadA mutant, thus supporting the annotation of its disrupted gene.