Similar Datasets
Project description:Ribosome pausing slows down translation and can affect protein synthesis. Improving translation efficiency can therefore be of commercial value. Here, we investigated the occurrence of ribosome pausing during amylase secretion by the industrial production organism Bacillus subtilis under semi fed-batch fermentation conditions. We first assessed our ribosome profiling setup by inducing ribosome stalling at isoleucine codons using the antibiotic mupirocin, and found a pause preference for isoleucine codons preceded by E and P site codons with guanosine residues in their first nucleotide position. Interestingly, when we applied standard ribosomal profiling conditions we found again an enrichment of guanosine residues in the E and P site of ribosome pause sites, but this time also upstream of the ribosome pause site. This sequence motif deviates from previously described ribosome pausing motifs. For the highly expressed amylase gene amyM several strong ribosome pausing sites were detected, which remained present during the 64-hour long fermentation, and were neither related to rare codons nor to secondary protein structures. When surveying the genome, an interesting finding was the presence of strong ribosome pausing sites in several toxins genes. These potential ribosome stall sites may function in preventing inadvertent activity in the cytosol.
2024-01-01 | GSE250313 | GEO
Project description:Ribosome pausing slows down translation and can affect protein synthesis. Improving translation efficiency can therefore be of commercial value. Here, we investigated the occurrence of ribosome pausing during amylase secretion by the industrial production organism Bacillus subtilis under semi fed-batch fermentation conditions. We first assessed our ribosome profiling setup by inducing ribosome stalling at isoleucine codons using the antibiotic mupirocin, and found a pause preference for isoleucine codons preceded by E and P site codons with guanosine residues in their first nucleotide position. Interestingly, when we applied standard ribosomal profiling conditions we found again an enrichment of guanosine residues in the E and P site of ribosome pause sites, but this time also upstream of the ribosome pause site. This sequence motif deviates from previously described ribosome pausing motifs. For the highly expressed amylase gene amyM several strong ribosome pausing sites were detected, which remained present during the 64-hour long fermentation, and were neither related to rare codons nor to secondary protein structures. When surveying the genome, an interesting finding was the presence of strong ribosome pausing sites in several toxins genes. These potential ribosome stall sites may function in preventing inadvertent activity in the cytosol.
2024-01-01 | GSE250312 | GEO
Project description:Ribosome profiling reveals conserved guanosine residues at ribosome pausing sites in Bacillus subtilis
| PRJNA1053350 | ENA
Project description:BackgroundRibosome pausing slows down translation and can affect protein synthesis. Improving translation efficiency can therefore be of commercial value. In this study, we investigated whether ribosome pausing occurs during production of the α-amylase AmyM by the industrial production organism Bacillus subtilis under repeated batch fermentation conditions.ResultsWe began by assessing our ribosome profiling procedure using the antibiotic mupirocin that blocks translation at isoleucine codons. After achieving single codon resolution for ribosome pausing, we determined the genome wide ribosome pausing sites for B. subtilis at 16 h and 64 h growth under batch fermentation. For the highly expressed α-amylase gene amyM several strong ribosome pausing sites were detected, which remained during the long fermentation despite changes in nutrient availability. These pause sites were neither related to proline or rare codons, nor to secondary protein structures. When surveying the genome, an interesting finding was the presence of strong ribosome pausing sites in several toxins genes. These potential ribosome stall sites may prevent inadvertent activity in the cytosol by means of delayed translation.ConclusionsExpression of the α-amylase gene amyM in B. subtilis is accompanied by several ribosome pausing events. Since these sites can neither be predicted based on codon specificity nor on secondary protein structures, we speculate that secondary mRNA structures are responsible for these translation pausing sites. The detailed information of ribosome pausing sites in amyM provide novel information that can be used in future codon optimization studies aimed at improving the production of this amylase by B. subtilis.
| S-EPMC11770953 | biostudies-literature
Project description:High-throughput methods, such as ribosome profiling, have revealed the complexity of translation regulation in Bacteria and Eukarya with large-scale effects on cellular functions. In contrast, the translational landscape in Archaea remains mostly unexplored. Here, we developed ribosome profiling in a model archaeon, Haloferax volcanii, elucidating, for the first time, the translational landscape of a representative of the third domain of life. We determined the ribosome footprint of H. volcanii to be comparable in size to that of the Eukarya. We linked footprint lengths to initiating and elongating states of the ribosome on leadered transcripts, operons, and on leaderless transcripts, the latter representing 70% of H. volcanii transcriptome. We manipulated ribosome activity with translation inhibitors to reveal ribosome pausing at specific codons. Lastly, we found that the drug harringtonine arrested ribosomes at initiation sites in this archaeon. This drug treatment allowed us to confirm known translation initiation sites and also reveal putative novel initiation sites in intergenic regions and within genes. Ribosome profiling revealed an uncharacterized complexity of translation in this archaeon with bacteria-like, eukarya-like, and potentially novel translation mechanisms. These mechanisms are likely to be functionally essential and to contribute to an expanded proteome with regulatory roles in gene expression.
| S-EPMC7261190 | biostudies-literature
Project description:This SuperSeries is composed of the SubSeries listed below.
2025-05-01 | GSE293288 | GEO
Project description:The journey of a newly synthesized polypeptide starts in the peptidyltransferase center of the ribosome, from where it traverses the exit tunnel. The interior of the ribosome exit tunnel is neither straight nor smooth. How the ribosome dynamics in vivo is influenced by the exit tunnel is poorly understood. Genome-wide ribosome profiling in mammalian cells reveals elevated ribosome density at the start codon and surprisingly the downstream 5th codon position as well. We found that the highly focused ribosomal pausing shortly after initiation is attributed to the geometry of the exit tunnel, as deletion of the loop region from ribosome protein L4 diminishes translational pausing at the 5th codon position. Unexpectedly, the ribosome variant undergoes translational abandonment shortly after initiation, suggesting that there exists an obligatory step between initiation and elongation commitment. We propose that the post-initiation pausing of ribosomes represents an inherent signature of the translation machinery to ensure productive translation.
| S-EPMC4085768 | biostudies-literature
Project description:The stringent response represses translation and is activated when amino acid levels drop, for example during the stationary phase. Bacillus subtilis, a well-known industrial enzyme production organism, secretes most enzymes during the stationary phase. We were curious whether the stringent response affects ribosome pausing, and whether its absence improves protein production yields in the stationary phase. To investigate this, genome-wide ribosome profiling was used using a stringent response mutant that overexpressed the α-amylase AmyM. Although, blocking the stringent response did increases overall protein synthesis, the secretion of AmyM was actually reduced. The ribosome profiling data revealed that this was not caused by a reduction in translation. In fact, absence of the stringent response did not seem to markedly influence ribosome pausing. However, late in stationary phase an increased ribosome pausing at tryptophane codons emerges, suggesting a depletion of tryptophane. A strong suppression of tryptophane biosynthesis and acquisition genes, under control of the trp RNA-binding attenuation protein TRAP, likely accounts for this, although TRAP does not belong to the stringent response regulon of B. subtilis. Finally, the ribosome profiles revealed several genes with unusually low translation activities, illustrating the importance of translation initiation as a regulatory element of expression.
2025-05-01 | GSE293165 | GEO
Project description:The stringent response represses translation and is activated when amino acid levels drop, for example during the stationary phase. Bacillus subtilis, a well-known industrial enzyme production organism, secretes most enzymes during the stationary phase. We were curious whether the stringent response affects ribosome pausing, and whether its absence improves protein production yields in the stationary phase. To investigate this, genome-wide ribosome profiling was used using a stringent response mutant that overexpressed the α-amylase AmyM. Although, blocking the stringent response did increases overall protein synthesis, the secretion of AmyM was actually reduced. The ribosome profiling data revealed that this was not caused by a reduction in translation. In fact, absence of the stringent response did not seem to markedly influence ribosome pausing. However, late in stationary phase an increased ribosome pausing at tryptophane codons emerges, suggesting a depletion of tryptophane. A strong suppression of tryptophane biosynthesis and acquisition genes, under control of the trp RNA-binding attenuation protein TRAP, likely accounts for this, although TRAP does not belong to the stringent response regulon of B. subtilis. Finally, the ribosome profiles revealed several genes with unusually low translation activities, illustrating the importance of translation initiation as a regulatory element of expression.
2025-05-01 | GSE293166 | GEO
Project description:Ribosomal stalling is used to regulate gene expression and can occur in a species-specific manner. Stalling during translation of the MifM leader peptide regulates expression of the downstream membrane protein biogenesis factor YidC2 (YqjG) in Bacillus subtilis, but not in Escherichia coli. In the absence of structures of Gram-positive bacterial ribosomes, a molecular basis for species-specific stalling has remained unclear. Here we present the structure of a Gram-positive B. subtilis MifM-stalled 70S ribosome at 3.5-3.9 Å, revealing a network of interactions between MifM and the ribosomal tunnel, which stabilize a non-productive conformation of the PTC that prevents aminoacyl-tRNA accommodation and thereby induces translational arrest. Complementary genetic analyses identify a single amino acid within ribosomal protein L22 that dictates the species specificity of the stalling event. Such insights expand our understanding of how the synergism between the ribosome and the nascent chain is utilized to modulate the translatome in a species-specific manner.
| S-EPMC4423224 | biostudies-literature