Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.1.30.1 (S1 nuclease)
 3,660 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The Escherichia coli K-12 trxA gene, the gene encoding thioredoxin, has been cloned and sequenced. The DNA sequence includes 280 base pairs upstream and 46 base pairs downstream of the coding region. The downstream sequence contains the -35 region of the promoter of the rho gene. Northern analysis of the trxA mRNA and S1 nuclease mapping indicate the presence of two promoters for the trxA gene. Initiation from either promoter results in an mRNA containing two potential translation initiation codons, one of which could initiate synthesis of a protein 18 amino acids longer than the mature trxA gene product. The 3' end of the gene, including the last eight codons, contains a stable stem-loop structure (delta G = -12.9 kcal) typical of a rho-independent transcription termination signal.
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PMID:Cloning and nucleotide sequence of the trxA gene of Escherichia coli K-12. 389 33

In this paper we describe an enhanced method for the large scale production of high quality 13C/15N labelled NTPs. High amounts of labelled RNA was obtained from E. coli cells grown in 13C/15N enriched medium and treated with chloramphenicol. Total RNA was extracted from spheroplasted cells in the presence of SDS and proteinase K and subsequently degraded to NMPs by nuclease P1 and high concentrations of nuclease S1 in a low salt buffer. To avoid non-specific degradation of the RNA, nuclease digestion was performed in a short term reaction on native, not heat-denatured RNA. CMP, AMP, GMP and UMP were chromatographically separated and converted to the corresponding NTPs by a mixture of kinases in the presence of a coupled redox system based on thioredoxin and dithiothreitol. The quality of the 13C/15N labelled NTPs was tested by in vitro transcription.
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PMID:A method for production of 13C/15N double labelled RNA in E. coli, and subsequent in vitro synthesis of ribonucleotide 5' triphosphates. 754 14

The degradation of individual mRNAs in Escherichia coli has been studied through the use of a multiple mutant carrying the pnp-7 (polynucleotide phosphorylase), rnb-500 (RNase II), and rne-1 (RNase E) alleles. In this triple mutant, discrete mRNA breakdown products are stabilized in vivo at the nonpermissive temperature (Arraiano, C. M., S. D. Yancey, and S. R. Kushner, J. Bacteriol. 170:4625-4633, 1988). In the case of thioredoxin (trxA) mRNA decay, degradation fragments accumulated at early times after a shift to the nonpermissive temperature. Using Northern (RNA) blots, S1 nuclease analysis, and primer extensions, we identified a series of specific endonucleolytic cleavage sites that occur throughout the transcript in both the triple mutant and a wild-type control. The implications of the complex decay patterns observed are discussed.
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PMID:Identification of endonucleolytic cleavage sites involved in decay of Escherichia coli trxA mRNA. 767 84