Assuntos
Escherichia coli/genética , RNA Bacteriano/química , RNA Bacteriano/genética , RNA Ribossômico 23S/química , RNA Ribossômico 23S/genética , Proteínas de Bactérias/metabolismo , Sequência de Bases , Sítios de Ligação/genética , Escherichia coli/metabolismo , Dados de Sequência Molecular , Mutação , Conformação de Ácido Nucleico , Plasmídeos/genética , RNA Bacteriano/metabolismo , RNA Ribossômico 23S/metabolismo , Proteínas Ribossômicas/metabolismoRESUMO
Expanded versions of the Ribosomal RNA Mutation Databases provide lists of mutated positions in 16S and 16S-like ribosomal RNA (16SMDBexp) and 23S and 23S-like ribosomal RNA (23SMDBexp) and the identity of each alteration. Alterations from organisms other than Escherichia coli are reported at positions according to the E.coli numbering system. Information provided for each mutation includes: (i) a brief description of the phenotype(s) associated with each mutation, (ii) whether a mutant phenotype has been detected by in vivo or in vitro methods, and (iii) relevant literature citations. The databases are available via ftp and on the World Wide Web at the following URL: http: //www.fandm.edu/Departments/Biology/Databases/RNA.h tml
Assuntos
Bases de Dados Factuais , Mutação , RNA Ribossômico 16S , RNA Ribossômico 23S , Redes de Comunicação de Computadores , Escherichia coli/genética , Armazenamento e Recuperação da InformaçãoRESUMO
The Ribosomal RNA Mutation Databases (16SMDB and 23SMDB) provide lists of mutated positions in 16S and 23S ribosomal RNA from Escherichia coli and the identity of each alteration. Information provided for each mutation includes: (i) a brief description of the phenotype(s) associated with each mutation; (ii) whether a mutant phenotype has been detected by in vivo or in vitro methods; and (iii) relevant literature citations. The databases are available via ftp and on the World Wide Web. Expansion of the databases to include information about mutations isolated in organisms other than E.coli is currently in progress.
Assuntos
Bases de Dados Factuais , Escherichia coli/genética , Mutação , RNA Ribossômico 16S/genética , RNA Ribossômico 23S/genética , FenótipoRESUMO
The 16S ribosomal RNA mutation database (16SMDB) provides a list of mutated positions in 16S ribosomal RNA from Escherichia coli and the identity of each alteration. Information provided for each mutation includes: (i) a brief description of the phenotype(s) associated with each mutation; (ii) whether a mutant phenotype has been detected by in vivo or in vitro methods; (iii) relevant literature citations. The database is available via ftp and on the World Wide Web.
Assuntos
Bases de Dados Factuais , Escherichia coli/genética , RNA Ribossômico 16S/genética , Redes de Comunicação de Computadores , Mutação , FenótipoRESUMO
The 23S Ribosomal RNA Mutation Database (23SMDB), provides a list of mutated positions in 23S ribosomal RNA from Escherichia coli and the identity of each alteration. Information provided for each mutation includes: (i) a brief description of the phenotypes(s) associated with each mutation, (ii) whether a mutant phenotype has been detected by in vivo or in vitro methods, and (iii) relevant literature citations. The database is available via ftp and on the World Wide Web.
Assuntos
Bases de Dados Factuais , Escherichia coli/genética , Mutação , RNA Ribossômico 23S/genética , Redes de Comunicação de ComputadoresRESUMO
Mutations that disrupt each of seven specific G-C base pairs in 16S rRNA from Escherichia coli confer loss of expression of a plasmid-encoded 16S rRNA selectable marker (spectinomycin resistance). However, A-U replacement of G-C base pairs at nucleotides 359/52 or 1292/1245 in 16S rRNA permits normal expression of the marker. By contrast, A-U replacements at 146/176, 153/168, 350/339, or 1293/1244 are associated with loss of expression of the marker. These genetic studies are designed to determine the importance of specific base pairs by assessment of the structural and functional impairments of 16S rRNA molecules resulting from expression of base pair substitutions at these positions.
Assuntos
Escherichia coli/crescimento & desenvolvimento , Regulação Bacteriana da Expressão Gênica , Mutação Puntual , RNA Bacteriano , RNA Ribossômico 16S , Ampicilina/farmacologia , Sequência de Bases , Resistência Microbiana a Medicamentos , Eritromicina/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Modelos Genéticos , Dados de Sequência Molecular , Conformação de Ácido Nucleico , Plasmídeos/genética , Espectinomicina/farmacologiaAssuntos
Escherichia coli/genética , Conformação de Ácido Nucleico , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Sequência de Bases , Sequência Conservada , Análise Mutacional de DNA , Escherichia coli/metabolismo , Dados de Sequência Molecular , Mutagênese , Mutagênese Sítio-Dirigida , Plasmídeos , RNA Ribossômico 16S/química , Ribossomos/metabolismoRESUMO
The 16S ribosomal RNA mutation database (16SMDB), provides a list of mutated positions in 16S ribosomal RNA from Escherichia coli and the identity of each alteration. Information provided for each mutation includes: (1) a brief description of the phenotype(s) associated with each mutation, (2) whether a mutant phenotype has been detected by in vivo or in vitro methods, and (3) relevant literature citations. The database is available via ftp.
Assuntos
Bases de Dados Factuais , Mutação , RNA Ribossômico 16S/genética , Escherichia coli/genética , FenótipoRESUMO
Chi recombinational hotspots are sites around which the rate of Rec-promoted recombination in bacteriophage lambda is elevated. Examination of a derivative of lambda into which the plasmid pBR322 was inserted reveals that pBR322 lacks Chi sites. Using this lambda-pBR322 hybrid, we obtained mutations creating Chi sites at three widely separated loci within pBR322. Nucleotide sequence analysis reveals that the mutations are single base-pair changes creating the octamer 5' GCTGGTGG 3'. This sequence is present at three previously analyzed Chi sites in lambda, and all analyzed mutations creating or inactivating these Chi sites occur within this octamer. We conclude that Chi is 5' GCTGGTGG 3', or its complement, or both.
Assuntos
Bacteriófago lambda/genética , DNA/genética , Plasmídeos , Recombinação Genética , Sequência de Bases , Mapeamento Cromossômico , DNA Recombinante , MutaçãoRESUMO
We have developed a simple, reproducible microtechnique for obtaining metaphase chromosomes from peripheral blood of live mice. The method has been successful with mice of several different genetic backgrounds and has been repeated in three other laboratories.