Project description:The metabolic versatile hyperthermophilic dissimilatory sulfate-reducing archaeon, Archaeoglobus fulgidus VC-16, both utilize carbon monoxide as energy source and is highly resistant to toxic effects of CO. This metabolic capacity was investigated by transcriptional response to growth with CO of cultures supplemented with sulfate (S-CO) or thiosulfate (T-CO), and without external electron acceptor (CO-without election acceptor ).
Project description:A hyperthermophilic archaeon Thermococcus onnurineus NA1 can grow and produce H2 on a variety of CO-containing feed stocks such as by-product gas generated from steel-mill process. In this study we applied a long-term adaptive evolution to enhance H2 productivity. Through serial transfer of cell cultures with carbon monoxide (CO) as an energy source, we observed physiological changes in cell density, CO consumption rate and H2 production rate. To understand the underlying mechanism for the changes, we performed systems analysis of genomic, transcriptomic and epigenomic data. Genomic analysis of an evolved strain, designated as 156T, revealed that single or multiple bases were substituted, deleted or inserted in the sequence of the parental strain. A single point mutation in a putative transcriptional regulator (TON_1525) seemed to play a pivotal role in changing cellular phenotypes by increasing the expression level of genes of a CO dehydrogenase-hydrogenase gene cluster. Additionally, a mutation in an aromatic amino acid permease (TON_0820) contributed to increasing cell growth. Transcriptomic analysis revealed that genes belonging to the categories of transcription, translation and energy metabolism in archaeal Clusters of Orthologous Genes (arCOGs) were significantly changed. In particular, genes involved in energy conservation via CO oxidation were highly upregulated. Epigenomic analysis suggested that methylation change might be a way of gene regulation in a hyperthermophilic archaeon. The evolved 156T strain showed highly enhanced hydrogen productivity with CO at high flow rates of 800 ml min-1 and above, indicating the adaptation rendered the strain less sensitive to high CO. The 156T strain was demonstrated to be appropriate for H2 production by using synthetic gas obtained by coal gasification. This study is the first example to show that evolutionary engineering is very effective in enhancing H2 productivity of a hyperthermophilic archaeon on CO
Project description:A strong promoter increases transcription of the genes of interest and enhances the production of various valuable substances. For a hyperthermophilic archaeon Thermococcus onnurineus NA1, which can produce H2 by carbon monoxide oxidation, we searched for a novel endogenous strong promoter by transcriptome analysis using high-throughput RNA sequencing. Based on the relative transcript abundance, we selected one promoter to encode a hypothetical gene, of which homologs were found only in several Thermococcales strains. This promoter, PTN0510, was introduced into the front of CO-responsible hydrogenase gene cluster encoding a carbon monoxide dehydrogenase (CODH), a hydrogenase and a Na+/H+ antiporter. In the resulting mutant strain, KS0510, transcription and translation level of the gene cluster increased by 4- to 14-folds and 1.5- to 1.9-folds, respectively, in comparison with those of wild-type strain. Additionally, H2 production rate of KS0510 mutant was 4.8-fold higher than that of wild-type strain. The PTN0510 was identified to be much stronger than the well-known two strong promoters, gdh and slp promoters from Thermococcus strains, through RT-qPCR and western blotting analyses and kinetics of H2 production. In this study, we demonstrated that the RNA-seq approach is a good strategy to mine a novel strong promoter of use to a Thermococcus strain when developed as a biotechnologically promising strain to produce valuable metabolites through a metabolic engineering. RNA expreesion profile of T. onnurineus NA1 genes in CO-containing media, in duplicate, using Illumina HiSeq 2500
Project description:A strong promoter increases transcription of the genes of interest and enhances the production of various valuable substances. For a hyperthermophilic archaeon Thermococcus onnurineus NA1, which can produce H2 by carbon monoxide oxidation, we searched for a novel endogenous strong promoter by transcriptome analysis using high-throughput RNA sequencing. Based on the relative transcript abundance, we selected one promoter to encode a hypothetical gene, of which homologs were found only in several Thermococcales strains. This promoter, PTN0510, was introduced into the front of CO-responsible hydrogenase gene cluster encoding a carbon monoxide dehydrogenase (CODH), a hydrogenase and a Na+/H+ antiporter. In the resulting mutant strain, KS0510, transcription and translation level of the gene cluster increased by 4- to 14-folds and 1.5- to 1.9-folds, respectively, in comparison with those of wild-type strain. Additionally, H2 production rate of KS0510 mutant was 4.8-fold higher than that of wild-type strain. The PTN0510 was identified to be much stronger than the well-known two strong promoters, gdh and slp promoters from Thermococcus strains, through RT-qPCR and western blotting analyses and kinetics of H2 production. In this study, we demonstrated that the RNA-seq approach is a good strategy to mine a novel strong promoter of use to a Thermococcus strain when developed as a biotechnologically promising strain to produce valuable metabolites through a metabolic engineering.
Project description:Investigating the role of carbon monoxide and a CO sensor protein CooA in the physiology of Desulfovibrio vulgaris Hildenborough using whole genome expression analysis Comparison of whole genome expression changes in the wild type and a strain deleted for CooA (DVU2097) in the presence and absence of carbon monoxide
Project description:Transcriptional profiling of M. tuberculosis growing in log phase treated with various concentrations of carbon monoxide versus untreated controls Keywords: Dose response
Project description:Investigating the role of carbon monoxide and a CO sensor protein CooA in the physiology of Desulfovibrio vulgaris Hildenborough using whole genome expression analysis