Project description:A potential origin that appears to stay dormant in its native host Haloferax volcanii lacking the main active origins becomes activated and competent for replication of the entire chromosome when integrated into the chromosome of the origin-deleted H. mediterranei. Measurement of replication dynamics (marker frequency analysis; MFA) for Haloferax mediterranei H13
Project description:A potential origin that appears to stay dormant in its native host Haloferax volcanii lacking the main active origins becomes activated and competent for replication of the entire chromosome when integrated into the chromosome of the origin-deleted H. mediterranei.
Project description:Transcriptome analysis based on total RNA-seq was performed on different Haloferax volcanii strains including mutants strains iincluding deletion strains for two small proteins. Differential expression analysis showed that a subset of genes were found to be regulated in the absence of the small proteins.
Project description:Transcriptional profiling of Haloferax mediterranei DF50 and M-NM-^TdeoR2 with induction by fructose comparing with the strains without this induction. Goal was to explore the effect of induction by fructose on Haloferax mediterranei. Total RNA from the Haloferax mediterranei DF50 and M-NM-^TdeoR2 with or without induction by fructose were used to generate target cDNA, and then hybridized to Haloferax mediterranei genome array genechips, representing about 3800 genes.
Project description:Transcriptional profiling of Haloferax mediterranei DF50 and ΔdeoR2 with induction by fructose comparing with the strains without this induction. Goal was to explore the effect of induction by fructose on Haloferax mediterranei.
Project description:Transcriptional profiling of Haloferax mediterranei comparing control wild-type strain with M-NM-^TphaA1 strain, in which phaA1 gene are knockouted. M-NM-^TphaA1 strain can accumulate PHB only. Goal was to explore the PHA biosynthetic pathway and to determine their impact on primary metabolism in H. mediterranei. Total RNA from the control Haloferax mediterranei and its M-NM-^TphaA1 strain were used to generate target cDNA, and then hybridized to 8*15K Haloferax mediterranei genome array genechips, representing about 3800 genes.
Project description:Transcriptional profiling of Haloferax mediterranei comparing control wild-type strain with M-NM-^TphaEC strain, in which PHA synthase genes are knockouted. M-NM-^TphaEC strain is deficient in PHBV accumulation. Goal was to explore the PHBV biosynthetic pathway and to determine their impact on primary metabolism in H. mediterranei. Total RNA from the control Haloferax mediterranei and its M-NM-^TphaEC strain were used to generate target cDNA, and then hybridized to 8*15K Haloferax mediterranei genome array genechips, representing about 3800 genes.
Project description:An in-depth glycoproteomic analysis of Haloferax volcanii has been performed, comparing the wildtype H53 with knockout mutants of aglB and agl15. While AglB-dependent glycosylation has been described to occur under standard culture conditions, the Agl15-dependent glycosylation pathway has previously been described to be only active under low-salt conditions. In this dataset, the largest archaeal glycoproteome could be identified with more than 40 N-glycoproteins and more than 100 N-glycopptides. It reveals not only that both glycosylation pathways can be active under the same conditions but also that the same glycosites can be modified by different glycans from both glycosylation pathways.
Project description:For microbial cells, an appropriate response to changing environmental conditions is critical for viability. Transcription regulatory proteins, or transcription factors (TFs) sense environmental signals to change gene expression. However, it remains unclear how TFs and their corresponding gene regulatory networks are selected for over evolutionary time scales. The function of TFs and how they evolve are particularly understudied in archaeal organisms. Here we identified, characterized, and compared the function of the RosR transcription factor across three related species of hypersaline adapted model archaea. RosR was previously characterized as a global regulator of gene expression during oxidative stress in the species Halobacterium salinarum (HsRosR). Here we use functional genomics and quantitative phenotyping to demonstrate that, despite strong conservation of HsRosR across species, its function diverges substantially. Surprisingly, RosR in Haloferax volcanii and Haloferax mediterranei regulates genes whose products function in motility and the outer membrane, leading to significant defects in motility when rosR is deleted. Given weak conservation and degeneration in the RosR cis-regulatory sequence across species, we hypothesize that the RosR regulatory network is easily rewired during evolution across related species of archaea.