Molecular genetic mechanism of aromatic compound biodegradation of soil

초록

A Southern-hybridization analysis and size-selected DNA library screening led to the isolation of a 6.3-kbp S. setonii DNA fragment, from which the C12O-encoding genetic locus was found to be located within a 1.4-kbp DNA fragment. A complete nucleotide sequencing analysis of the 1.4-kbp DNA fragment revealed a 0.84-kbp ORF, which showed a strong overall amino acid similarity to the known high-G+C gram-positive bacterial mesophilic C12Os. The heterologous expression of the cloned 1.4-kbp DNA fragment in E. coli demonstrated that this C12O possessed a thermophilic activity within a broad temperature range and showed a higher activity against 3-methylcatechol than catechol or 4-methy-catechol, but no activity against protocatecuate.