Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0038187 (starvation)
 24,951 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The methylase encoded by erm genes and induced by erythromycin modifies the 23S rRNA and confers resistance to macrolide-lincosamide-streptogramin B antibiotics. Induction is due to a posttranscriptional mechanism in which the inducer activates translation of methylase mRNA by binding to unmethylated (erythromycin-sensitive) ribosomes and stalling them in the leader region. It is shown in this study that pseudomonic acid A, an inhibitor of isoleucyl-tRNA synthetase, can also induce methylase synthesis. Isoleucine starvation has a similar effect on ribosomes translating the ermC leader region to cause induction of methylase synthesis. These observations support the requirements for ribosome stalling and destabilization of a stem-loop structure and demonstrate that stalling can occur without macrolide-bound ribosomes.
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PMID:Induction of ermC methylase in the absence of macrolide antibiotics and by pseudomonic acid A. 250 38

We have isolated the structural genes for methionyl-tRNA synthetase (L-methionine:tRNAMet ligase, EC 6.1.1.10) and isoleucyl-tRNA synthetase (L-isoleucine:tRNAIle ligase, EC 6.1.1.5) from the yeast Saccharomyces cerevisiae by transformation. Both genes exist in a single copy in the yeast genome and show no homology to either yeast mitochondrial or Escherichia coli DNA as judged by Southern analysis. The region corresponding to the DNA segment altered in mes1 or ils1-1 mutants was defined by transformation of synthetase mutants with subclones of the respective gene. Although the isolated fragment containing the methionyl-tRNA synthetase gene complements the mes1 mutation in yeast, it does not complement the analogous metG mutation in E. coli. A single transcript of about 3100 nucleotides codes for the isoleucyl-tRNA synthetase. This transcript is about 2-fold elevated in strains starved for isoleucine, histidine, or arginine as compared to wild type. It is regulated by the general control of amino acid biosynthesis, which affects several biosynthetic pathways. Two polyadenylated transcripts are homologous to the methionyl-tRNA synthetase gene. The major MES1 transcript is not affected by the general control or starvation for several different amino acids, including methionine.
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PMID:Structure and expression of two aminoacyl-tRNA synthetase genes from Saccharomyces cerevisiae. 630 34

In the thermophilic archaeon Methanobacterium thermoautotrophicum Marburg, the structural gene for isoleucyl-tRNA synthetase (ileS) is flanked upstream by orf401 and downstream by purL. orf401 encodes a 43.5-kDa protein with an unknown function. Northern (RNA) hybridization and S1 nuclease protection experiments showed that the orf401, ileS, and purL genes are cotranscribed from an archael consensus promoter in front of orf401. The corresponding transcript was about eightfold increased in cells that had been exposed to pseudomonic acid A, a specific inhibitor of isoleucyl-tRNA synthetase. Growth inhibition by puromycin, tryptophan starvation, or starvation for hydrogen did not affect the level of this transcript. The level of a trpE transcript, however, was drastically elevated upon tryptophan starvation, while inhibition by pseudomonic acid A had no effect on the level of this transcript. Expression of ileS thus appears to be controlled by a regulatory mechanism which specifically responds to the availability of isoleucyl-tRNA. Extensive decay of the orf401-ileS-purL message was observed. Degradation occurred, presumably by endonucleolytic cleavage, within the orf401 region.
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PMID:Transcription of the ileS operon in the archaeon Methanobacterium thermoautotrophicum Marburg. 837 40