Cloning and characterization of catechol catabolic operon from Streptomyces setonii

초록

A 6.3 kbp PstI DNA fragment containing a catechol catabolic operon and a part of benzoate catabolic operon from Streptomyces setonii (ATCC 39116) has been cloned into a streptomycetes-E. coli shuttle vector (named pESK003) and completely sequenced. A catechol catabolic operon revealed a unique gene arrangement with all four translationally-coupled open reading frames (in order): catR, a putative regulatory gene; catB, a muconate cycloisomerase gene; catA, catechol 1,2-dioxygenase gene; catC, muconate isomerase. Another divergently transcribed operon (probably involved in the conversion of benzoate to catechol) including benA, benB and a part of benC was also found at the upstream of catechol catabolic operon. A catechol operon of pESK003 in a heterologous S. lividans was specifically induced by phenol but not by catechol or benzoate, implying a unusual catR-mediated regulation mechanism of catechol catabolism in Streptomyces setonii.