RT Journal Article SR Electronic(1) A1 Frenkiel, HéléeGne A1 Bardowski, Jacek A1 Ehrlich, S. Dusko A1 Chopin, AlainYR 1998 T1 Transcription of the trp operon in Lactococcus lactis is controlled by antitermination in the leader region JF Microbiology, VO 144 IS 8 SP 2103 OP 2111 DO https://doi.org/10.1099/00221287-144-8-2103 PB Microbiology Society, SN 1465-2080, AB The regulatory functions of the leader region preceding the Lactococcus lactis trp operon have been studied by mutagenesis analysis. This leader presents striking similarity to ‘T-box’ leaders found upstream of many Gram-positive aminoacyl-tRNA synthetase genes and some amino acid biosynthesis operons, which are controlled by antitermination through interaction of the leader transcript with cognate uncharged tRNA. A region of the L. lactis leader transcript also contains a series of (G/U)AG repeats which, in Bacillus, are involved in the binding of the trp RNA-binding protein (TRAP) which controls trp transcription. A screen was developed for the isolation of regulatory mutants affected in the leader region. All spontaneous mutants contained deletions; point mutations were only obtained after UV-induced mutagenesis. All mutations affected the putative transcription terminator upstream of the trp operon, demonstrating that trp is indeed controlled by transcription antitermination., UL https://www.microbiologyresearch.org/content/journal/micro/10.1099/00221287-144-8-2103