Zinc is a key factor in controlling alternation of two types of L31 protein in the Bacillus subtilis ribosome.
We have analysed changes in the composition of ribosomal proteins during cell growth in Bacillus subtilis. Ribosome fractions were prepared from B. subtilis cells at different phases of growth and were separated by radical-free and highly reducing (RFHR) two-dimensional polyacrylamide gel electrophoresis. We identified 50 ribosomal proteins, including two paralogues of L31 protein (RpmE and YtiA). Although the ribosome fraction extracted from exponentially growing cells contained RpmE protein, this protein disappeared during the stationary phase. In contrast, YtiA was detected in the ribosome fraction extracted after the end of exponential growth. Expression of the ytiA gene encoding YtiA was found to be negatively controlled by Zur, a zinc-specific transcriptional repressor that controls zinc transport operons. Analysis by inductively coupled plasma mass spectrometry (ICP-MS) indicated that RpmE contains one zinc ion per molecule of protein. In addition, mutagenesis of the rpmE gene encoding RpmE revealed that Cys-36 and Cys-39, located within a CxxC motif, are required not only for binding zinc but also for the accumulation of RpmE in the cell. Taken together, these results indicate that zinc plays an essential role in the alternation between two types of L31 protein in the ribosome of B. subtilis.
Nanamiya
Hideaki
H
Laboratory of Molecular Genetics and Frontier Project Life's Adaptation Strategies to Environmental Changes, College of Science, Rikkyo University, Toshima-ku Nishi-ikebukuro 3-34-1, Tokyo 171-8501, Japan.
Akanuma
Genki
G
Natori
Yousuke
Y
Murayama
Rikinori
R
Kosono
Saori
S
Kudo
Toshiaki
T
Kobayashi
Kazuo
K
Ogasawara
Naotake
N
Park
Seung-Moon
SM
Ochi
Kozo
K
Kawamura
Fujio
F
D000595:Amino Acid Sequence; D019677:Artificial Gene Fusion; D001412:Bacillus subtilis / Q000254:growth & development* / Q000378:metabolism*; D001426:Bacterial Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D001483:Base Sequence; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000502:physiology; D015180:Electrophoresis, Gel, Two-Dimensional; D029968:Escherichia coli Proteins / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial; D005798:Genes, Bacterial; D017930:Genes, Reporter; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010802:Phylogeny; D011401:Promoter Regions, Genetic; D020543:Proteome / Q000032:analysis; D012269:Ribosomal Proteins / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics; D017385:Sequence Homology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D015032:Zinc / Q000378:metabolism*; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D020543:Proteome; D012269:Ribosomal Proteins; C114819:Zur protein, E coli; C050985:ribosomal protein L31; D001616:beta-Galactosidase; D015032:Zinc