In bacteria, tRNA molecules are produced as precursors with additional nucleotides both upstream and downstream of the tRNA coding sequence. To generate a mature tRNA, the endoribonuclease RNase P removes the upstream sequence, while a number of enzymes can remove the downstream sequence. In this report, the influence of these upstream and downstream sequences for the expression of mature functional tRNA was studied
Allostery in GroEL: Its Role in the Refolding of Protein Substrates
The Escherichia coli chaperonin GroEL assists in the re-folding of misfolded substrate proteins (SPs). In response to the binding of ATP, GroEL undergoes large, allosteric structural transitions, resulting in an expansion of its central cavity and a capping of the cavity by the co-chaperonin GroES. Bound SP is released into the central cavity following the [...]
Detection of enterohemorrhagic Escherichia coli (EHEC)
Escherichia coli is a natural inhabitant of the intestines of both humans and animals, but there are also several pathogenic types of E. coli which cause disease in humans. Strains of enterohemorrhagic E. coli (EHEC) have been associated with outbreaks of diarrhea, hemorrhagic colitis and hemolytic uremic syndrome in humans. Most clinical signs of disease [...]
Mutations and Mutation Rate in the Development of Fluoroquinolone Resistance
The emergence of multidrug resistant bacteria world wide is a serious problem, and very few new drugs are under development. The selection of resistant bacteria is affected by factors such as mutation rate, biological fitness cost and the rate of fitness compensation. This thesis is focused on how mutation rate affects resistance to fluoroquinolones and [...]