NUCLEOTIDE-SEQUENCES AND REGULATIONAL ANALYSIS OF GENES INVOLVED IN CONVERSION OF ANILINE TO CATECHOL IN PSEUDOMONAS-PUTIDA UCC22(PTDN1)

A 9,233-bp HindIII fragment of the aromatic amine catabolic plasmid pT DN1, isolated from a derivative of Pseudomonas putida mt-2 (UCC22), co nfers the ability to degrade aniline on P. putida KT2442. The fragment encodes six open reading frames which are arranged in the same direct ion. Their 5' upstream region is part of the direct-repeat sequence of pTDN1. Nucleotide sequence of 1.8 kb of the repeat sequence revealed only a single base pair change compared to the known sequence of IS107 1 which is involved in the transposition of the chlorobenzoate genes ( C. Nakatsu, J. Ng, R. Singh, N. Straus, and C. Wyndham, Proc. Natl, Ac ad, Sci, USA 88:8312-8316, 1991), Four open reading frames encode prot eins with considerable homology to proteins found in other aromatic-co mpound degradation pathways, On the basis of sequence similarity, thes e genes are proposed to encode the large and small subunits of aniline oxygenase (tdnA1 and tdnA2, respectively), a reductase (tdnB), and a LysR-type regulatory gene (tdnR). The putative large subunit has a con served [2Fe-2S]R Rieske-type ligand center, Two genes, tdnQ and tdnT, which may be involved in amino group transfer; are localized upstream of the putative oxygenase genes; The tdnQ gene product shares about 30 % similarity with glutamine synthetases; however, a pUC-based plasmid carrying tdnQ did not support the growth of an Escherichia coli glnA s train in the absence of glutamine, TdnT possesses domains that are con served among amidotransferases. The tdnQ, tdnA1, tdnA2, tdnB, and tdnR genes are essential for the conversion of aniline to catechol.