title: Ribosome-controlled transcription termination is essential for the production of antibiotic microcin C.
abstract: Microcin C (McC) is a peptide-nucleotide antibiotic produced by Escherichia coli cells harboring a plasmid-borne operon mccABCDE. The heptapeptide MccA is converted into McC by adenylation catalyzed by the MccB enzyme. Since MccA is a substrate for MccB, a mechanism that regulates the MccA/MccB ratio likely exists. Here, we show that transcription from a promoter located upstream of mccA directs the synthesis of two transcripts: a short highly abundant transcript containing the mccA ORF and a longer minor transcript containing mccA and downstream ORFs. The short transcript is generated when RNA polymerase terminates transcription at an intrinsic terminator located in the intergenic region between the mccA and mccB genes. The function of this terminator is strongly attenuated by upstream mcc sequences. Attenuation is relieved and transcription termination is induced when ribosome binds to the mccA ORF. Ribosome binding also makes the mccA RNA exceptionally stable. Together, these two effects-ribosome-induced transcription termination and stabilization of the message-account for very high abundance of the mccA transcript that is essential for McC production. The general scheme appears to be evolutionary conserved as ribosome-induced transcription termination also occurs in a homologous operon from Helicobacter pylori.
authors.affiliation: Institute of Gene Biology of the Russian Academy of Sciences, Moscow, Russia Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry, Rutgers, the State University of New Jersey, Piscataway, NJ, USA St. Petersburg State Polytechnical University, St. Petersburg, Russia.
authors.forename: Inna
authors.initials: I
authors.lastname: Zukher
authors.affiliation: Institute of Gene Biology of the Russian Academy of Sciences, Moscow, Russia.
authors.forename: Maria
authors.initials: M
authors.lastname: Novikova
authors.affiliation: Institute of Molecular Genetics of the Russian Academy of Sciences, Moscow, Russia.
authors.forename: Anton
authors.initials: A
authors.lastname: Tikhonov
authors.affiliation: Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Mikhail V
authors.initials: MV
authors.lastname: Nesterchuk
authors.affiliation: Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Ilya A
authors.initials: IA
authors.lastname: Osterman
authors.affiliation: Faculty of Biology, University of Belgrade, Belgrade, Serbia.
authors.forename: Marko
authors.initials: M
authors.lastname: Djordjevic
authors.affiliation: Department of Chemistry, Lomonosov Moscow State University, Moscow, Russia.
authors.forename: Petr V
authors.initials: PV
authors.lastname: Sergiev
authors.affiliation: Research Centre for Infectious Diseases (ZINF), University of Würzburg, Würzburg, Germany.
authors.forename: Cynthia M
authors.initials: CM
authors.lastname: Sharma
authors.affiliation: Institute of Gene Biology of the Russian Academy of Sciences, Moscow, Russia Waksman Institute for Microbiology and Department of Molecular Biology and Biochemistry, Rutgers, the State University of New Jersey, Piscataway, NJ, USA St. Petersburg State Polytechnical University, St. Petersburg, Russia Skolkovo Institute of Science and Technology, Skolkovo, Russia severik@waksman.rutgers.edu.
authors.forename: Konstantin
authors.initials: K
authors.lastname: Severinov
mesh_terms: D000900:Anti-Bacterial Agents / Q000096:biosynthesis* / Q000737:chemistry; D001430:Bacteriocins / Q000096:biosynthesis* / Q000737:chemistry / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism; D029968:Escherichia coli Proteins / Q000235:genetics; D019143:Evolution, Molecular; D016480:Helicobacter pylori / Q000235:genetics; D008025:Ligases / Q000235:genetics; D009876:Operon; D020871:RNA Stability; D012329:RNA, Bacterial / Q000096:biosynthesis / Q000378:metabolism; D012270:Ribosomes / Q000378:metabolism*; D061806:Transcription Termination, Genetic
chemical_list: D000900:Anti-Bacterial Agents; D001430:Bacteriocins; D029968:Escherichia coli Proteins; D012329:RNA, Bacterial; C020411:microcin; D008025:Ligases; C542496:MccB protein, E coli