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)

A marked breakdown of ribosomes and rRNA occurs in Escherichia coli cells during prolonged deprivation of a carbon source (energy starvation). In E. coli recovering from energy starvation: (a) synthesis of RNA started immediately, total protein synthesis showed a delay of 5 to 10 minutes; (b) beta-galactosidase, tryptophanase and serine deaminase could not be induced in the first 50--70 min; (c) a lag of 60 min in the synthesis of beta-galactosidase was observed in a lac constitutive mutant of E. coli; synthesis of the constitutive enzyme malate dehydrogenase did not shown any delay. RNA synthesized in the early stages of recovery contained a higher percentage of low molecular weight molecules than RNA synthesized after 70 min of recovery or during exponential growth. Messenger RNA specific for beta-galactosidase was not synthesized for the first 50--60 min of recovery even when the specific inducer was added to the cultures.
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PMID:Synthesis of inducible enzyme in Escherichia coli recovering from prolonged energy starvation. 18 24

Starvation and diabetes both caused a dramatic induction of hepatic L-serine dehydratase (SDH) (EC 4.2.1.13) in rats. Increases in the activity of the enzyme which had been demonstrated in several previous studies were found to be associated with increases in the amount of SDH protein and its mRNA in our studies reported herein. Nuclear run-on experiments with isolated liver nuclei demonstrated that the increases in SDH activity were mainly the result of increases in the rate of SDH gene transcription. Refeeding of glucose to starved rats or the administration of insulin to diabetic rats caused a marked reduction in the amount of SDH mRNA. The rates of transcription as measured in isolated nuclei were reduced to uninduced levels within 30 min of either treatment. Following the administration of Bt2-cAMP, the transcription rates of the SDH gene returned to the original induced rates within 40 min both in glucose-refed rats and in diabetic rats administered insulin. The results of these experiments indicate that the induction of SDH in rat liver in vivo is controlled predominantly at the level of gene transcription by the reciprocal action of cAMP and insulin.
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PMID:Effects of glucose, insulin, and cAMP on transcription of the serine dehydratase gene in rat liver. 165 38

Inactivation of ccpA in Enterococcus faecalis leads to reduction of the growth rate, derepression of the galKETR operon in the presence of a mixture of glucose and galactose, and reduction of transcription of ldh in the presence of glucose. Moreover, the E. faecalis ccpA gene fully complements a Bacillus subtilis ccpA mutant, arguing for similar functions of these two homologous proteins. Protein comparison on two-dimensional gels from the wild-type cells and the ccpA mutant cells revealed a pleiotropic effect of the mutation on gene expression. The HPr protein of the carbohydrate-phosphotransferase system was identified by microsequencing, and a modification of its phosphorylation state was observed between the wild-type and the mutant strains. Moreover, at least 16 polypeptides are overexpressed in the mutant, and 6 are repressed. Interestingly, 13 of the 16 polypeptides whose synthesis is enhanced in the mutant were also identified as glucose starvation proteins. The N-terminal amino acid sequences of four of them match sequences deduced from genes coding for L-serine dehydratase, dihydroxyacetone kinase (two genes), and a protein of unknown function from Deinococcus radiodurans.
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PMID:Characterization of the ccpA gene of Enterococcus faecalis: identification of starvation-inducible proteins regulated by ccpA. 1100 80

Biofilm development in Bacillus subtilis is regulated at multiple levels. While a number of known signals that trigger biofilm formation do so through the activation of one or more sensory histidine kinases, it was discovered that biofilm activation is also coordinated by sensing intracellular metabolic signals, including serine starvation. Serine starvation causes ribosomes to pause on specific serine codons, leading to a decrease in the translation rate of sinR, which encodes a master repressor for biofilm matrix genes and ultimately triggers biofilm induction. How serine levels change in different growth stages, how B. subtilis regulates intracellular serine levels, and how serine starvation triggers ribosomes to pause on selective serine codons remain unknown. Here, we show that serine levels decrease as cells enter stationary phase and that unlike most other amino acid biosynthesis genes, expression of serine biosynthesis genes decreases upon the transition into stationary phase. The deletion of the gene for a serine deaminase responsible for converting serine to pyruvate led to a delay in biofilm formation, further supporting the idea that serine levels are a critical intracellular signal for biofilm activation. Finally, we show that levels of all five serine tRNA isoacceptors are decreased in stationary phase compared with exponential phase. However, the three isoacceptors recognizing UCN serine codons are reduced to a much greater extent than the two that recognize AGC and AGU serine codons. Our findings provide evidence for a link between serine homeostasis and biofilm development in B. subtilis IMPORTANCE In Bacillus subtilis, biofilm formation is triggered in response to environmental and cellular signals. It was proposed that serine limitation acts as a proxy for nutrient status and triggers biofilm formation at the onset of biofilm entry through a novel signaling mechanism caused by global ribosome pausing on selective serine codons. In this study, we reveal that serine levels decrease at the biofilm entry due to catabolite control and a serine shunt mechanism. We also show that levels of five serine tRNA isoacceptors are differentially decreased in stationary phase compared with exponential phase; three isoacceptors recognizing UCN serine codons are reduced much more than the two recognizing AGC and AGU codons. This finding indicates a possible mechanism for selective ribosome pausing.
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PMID:A Decrease in Serine Levels during Growth Transition Triggers Biofilm Formation in Bacillus subtilis. 3113 26