Project description:Here, we report the discovery of a novel mechanism of genetic complementation in M. marinum. We found that nonsense suppression was causing genetic complementation. Nonsense suppression was linked to alterations in cell permeability and exposure to the aminoglycoside antibiotic, hygromycin.
Project description:RNA helicases perform essential housekeeping and regulatory functions in all domains of life by binding and unwinding RNA molecules. The Ski2-like proteins are primordial helicases that play an active role in eukaryotic RNA homeostasis pathways, with multiple homologs having specialized functions. The significance of the expansion and diversity of Ski2-like proteins in Archaea, the third domain of life, has not yet been established. Here, by studying the phylogenetic diversity of Ski2-like helicases among archaeal genomes and the enzymatic activities of those in Thermococcales, we provide further evidence of the function of this protein family in archaeal metabolism of nucleic acids. We show that, in the course of evolution, ASH-Ski2 and Hel308-Ski2, the two main groups of Ski2-like proteins, have diverged in their biological functions. Whereas Hel308 has been shown to mainly act on DNA, we show that ASH-Ski2, previously described to be associated with the 5′-3′ aRNaseJ exonuclease, acts on RNA by supporting an efficient annealing activity, but also an RNA unwinding with a 3′-5′ polarity. To gain insights into the function of Ski2, we also analyse the transcriptome of Thermococcus barophilus ASH-Ski2 mutant strain and provide evidence of the importance of ASH-Ski2 in cellular metabolism pathways related to translation.
Project description:Heterologous gene expression to expand the native genetic capability of E. coli is the backbone of protein expression and metabolic engineering. The goal of this study was to determine how the identity of the heterologous gene expressed affected the host cell transcriptome. We generated a library of E. coli expressing 46 heterologous genes through an identical rhamnose inducible expression system and perform high throughput ribosome profiling.
