POSTTRANSCRIPTIONAL CONTROL OF PSEUDOMONAS-AERUGINOSA LASB EXPRESSIONINVOLVES THE 5'-UNTRANSLATED REGION OF THE MESSENGER-RNA

To investigate the regulatory role of the 5' untranslated region of Ps eudomonas aeruginosa lasB mRNA, several lasB-lacZ protein and operon f usions were generated. By examining expression of these fusions in str ain PAO1 we showed that the 5' untranslated leader sequence was involv ed in the post-transcriptional iron regulation of elastase. Two compon ents of the unusually long 139 nucleotide lasB 5' untranslated region may be involved in post-transcriptional control. The first 101 nucleot ides of the lasB mRNA may contain a translational enhancer element and an element that enhances transcript accumulation. However, the iron r esponsive element in the lasB mRNA requires sequences downstream of nu cleotide +104. (C) 1998 Federation of European Microbiological Societi es. Published by Elsevier Science B.V.