细胞功能测定

Chemical probing of RNA structure has become one of the most popular approaches to map the conformation of RNA molecules of various sizes under well-defined experimental conditions. The method monitors the sensitivity of each nucleotide to various chemicals, which reflects its hydro ...

The heat shock (HS) response is the major cellular defense mechanism against acute exposure to environmental stresses. The hallmark of the HS response, which is conserved in all eukaryotes, is the rapid and massive induction of expression of a set of cytoprotective genes. Most of the induction o ...

Riboswitches are vital components of many genomes. Covariance model searches for the characteristic architectures of riboswitch aptamer domains can be used to predict new examples of these structured RNAs. Since riboswitches generally function as cis-regulatory elements, ex ...

Riboswitches are non-coding RNA elements mainly located in the 5′ untranslated regions (UTR) of bacterial genes. They bind to small metabolites and upon binding conformational changes occur that trigger the expression of a certain gene. Riboswitches have been identified that bind to am ...

Regulation of gene expression in bacteria by cis-acting RNA elements can be investigated both in vivo and in vitro. Analyses in vivo can focus on changes in mRNA transcript levels or in protein production. Systems that are regulated at the level of premature termination of transcription are best ...

Small non-coding RNAs (sRNAs) are an emerging class of regulators of bacterial gene expression, which mainly modulate the translation of trans-encoded mRNAs. Typically, these molecules are 50–200 nucleotides in size and do not contain expressed open reading frames (ORFs). In Escheric ...

RNA cleavage is a catalytic reaction which defines many types of RNA processing events, including those of metabolite-sensing riboswitch, self-splicing introns, mRNA splicing, tRNA processing, polyA-cleavage, and various small ribozymes such as hairpin and hammerhead ribozy ...

Synthetic riboswitches constructed from RNA aptamers provide a means to control bacterial gene expression using exogenous ligands. A common theme among riboswitches that function at the translational level is that the RNA aptamer interacts with the ribosome-binding site (RBS) of a g ...

Riboswitches modulate gene expression in eubacteria and eukaryotes in response to changing concentrations of small molecule metabolites. In most examples studied to date, riboswitches achieve both metabolite sensing and gene control functions without the obligate involve ...

One of the most versatile riboswitch classes refers to purine nucleoside metabolism. In the cell, purine riboswitches of the respective mRNAs either act at the transcriptional or translational level and off- or on-regulate genes upon binding to their dedicated ligands. Biophysical st ...

Riboswitches are recently discovered messenger RNA motifs involved in gene regulation. They modulate gene expression at various levels, such as transcription, translation, splicing, and mRNA degradation. Because riboswitches exhibit relatively complex structures, they ...

Riboswitches encompass messenger ribonucleic acid transcripts that sense the concentration of small molecule metabolites through binding the target compound and then control the expression of metabolite-related genes in response to the metabolite concentration. While m ...

In this introductory chapter, I stress one more time the urgency to better connect molecular epidemiology and evolutionary biology. I show how much population genetics and phylogenetic analyses can confer a considerable added value to all attempts to characterize strains and species of ...

Salmonellosis is a common infection estimated to affect 3 billion people and to cause 200,000 deaths every year. Infections can appear as enteric fever, gastroenteritis, bacteremia, or extraintestinal focal infection. The course of the disease depends on a variety of factors, including ...

As the use of nucleotide sequence-based typing has become more widespread in the investigation of microbial epidemiology, there has been a natural requirement for curated Internet-based databases that can act as central authorities for nomenclature and type definitions. These fac ...

The molecular epidemiology of infectious diseases uses a variety of techniques to assay the relatedness of disease-causing organisms to identify strains responsible for outbreaks or associated with particular phenotypes of interest (such as antibiotic resistance) and, it is ho ...

In this chapter, I expose the main properties and theoretical background of a somewhat out-of-fashion technique, multilocus enzyme electrophoresis (MLEE). I show that the remarkable properties of this marker—clear Mendelian inheritance, codominance, strong phylogenetic si ...

To facilitate the study of plasmids and their roles in human and animal health, environmental processes, and microbial adaptation and evolution, plasmid classification has been an important focus of plasmid biologists over the years. Initial schemes were based on the ability of a plasmid to ...

The polymerase chain reaction (PCR) has essentially been designed to amplify specific regions within DNA molecules. This requires knowledge of the local nucleic acid sequence to design primer oligonucleotides. However, to generate DNA fingerprints, the PCR can be modified in a way that f ...

The use of defined primers for polymerase chain reaction (PCR) amplification of interspersed repetitive DNA elements present at distinct locations in prokaryotic genomes is referred to as repetitive element sequence based-polymerase chain reaction (rep-PCR). The initial dis ...