Organization and transcriptional characterization of the cat1 gene cluster in Acinetobacter lwoffi K24.

Previously, we have reported that two clustered cat genes from Acenitobacter lwoffi K24 had different arrangements, catB1C1A1 and catB2A2C2 (Kim, S.I., S.-H. Leem, J.-S. Choi, Y.H. Chung, S. Kim, Y.-M. Park, Y.K. Park, Y.N. Lee, and K.-S. Ha. 1997, J. Bacteriol. 179, 5226-5231). By further analysis of the organization of the cat1 gene cluster, we obtained a complete sequence of the catB1 gene, which encoded 40.8-kDa polypeptide containing 379 amino acids, and found a open reading frame (ORF) coding a putative regulatory protein in upstream region of catB1 on plasmid pCD1-1. This ORF encoded 34.2-kDa polypeptide containing 379 amino acids and had more than 40% identity with catR, LysR family regulatory protein of Pseudomonas putida. RT-PCR, Northern blot analysis and primer extension assay for transcriptional analysis of the cat1 gene cluster revealed that the catB1C1 genes were cotranscribed and the catA1 gene was independently transcribed.