A Corynebacterium glutamicum mutant with a defined deletion within the rplK gene is impaired in (p)ppGpp accumulation upon amino acid starvation.
The rplK gene of Corynebacterium glutamicum ATCC13032 comprises 438 nucleotides and encodes a protein of 145 amino acids with a molecular mass of 15.3 kDa. The amino acid sequence revealed extensive similarities to the large ribosomal subunit protein L11 from several Gram-positive and Gram-negative bacteria. The C. glutamicum rplK gene is located downstream of secE, representing part of the protein export apparatus, and of nusG, encoding a transcription antiterminator protein. The rplK gene is followed by an ORF homologous to rplA encoding the 50S ribosomal protein L1. Northern analysis revealed that transcription of the rplK-rplA cluster resulted in two different transcripts of 1.5 and 0.6 kb. The 1.5 kb transcript corresponds to the entire rplK-rplA cluster and the short transcript originates from the rplK gene. A C. glutamicum rplK mutant strain carrying a 12 bp in-frame deletion within rplK, which resulted in the loss of the tetrapeptide Pro-Ala-Leu-Gly in the L11 protein, was constructed. The mutant failed to accumulate (p)ppGpp in response to amino acid starvation and exhibited an increased tolerance to the antibiotic thiostrepton. Evidently, the C. glutamicum rplK gene is required for (p)ppGpp accumulation upon nutritional starvation.
Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, D-33501 Bielefeld, Germany1.
Lutz
L
Wehmeier
Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, D-33501 Bielefeld, Germany1.
Olaf
O
Brockmann-Gretza
Area Microbiologia, Dpto Ecologia, Genetica y Microbiologia, Facultad de Biologia, Universidad de Leon, Campus de Vegazana, E-24071 Leon, Spain2.
Agustin
A
Pisabarro
Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, D-33501 Bielefeld, Germany1.
Andreas
A
Tauch
Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, D-33501 Bielefeld, Germany1.
Alfred
A
Pühler
Area Microbiologia, Dpto Ecologia, Genetica y Microbiologia, Facultad de Biologia, Universidad de Leon, Campus de Vegazana, E-24071 Leon, Spain2.
Juan F
JF
Martin
Lehrstuhl für Genetik, Fakultät für Biologie, Universität Bielefeld, D-33501 Bielefeld, Germany1.
Jörn
J
Kalinowski
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D001483:Base Sequence; D003352:Corynebacterium / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D017353:Gene Deletion; D006158:Guanosine Pentaphosphate / Q000378:metabolism*; D008969:Molecular Sequence Data; D012269:Ribosomal Proteins / Q000235:genetics* / Q000378:metabolism; D013883:Thiostrepton / Q000494:pharmacology; D014158:Transcription, Genetic
D000596:Amino Acids; D000900:Anti-Bacterial Agents; D012269:Ribosomal Proteins; C027624:ribosomal protein L11; D006158:Guanosine Pentaphosphate; D013883:Thiostrepton