Project description:Abstract: The crenarchaeal order Sulfolobales collectively contains at least five major terminal oxidase complexes. Based on genome sequence information, all five complexes are found only in Metallosphaera sedula and Sulfolobus tokodaii, the two sequenced Sulfolobales capable of iron oxidization. While specific respiratory complexes in certain Sulfolobales have been characterized previously as proton pumps for maintaining intracellular pH and generating proton motive force (pmf), their contribution to sulfur and iron biooxidation has not been considered. For M. sedula growing in the presence of ferrous iron and reduced inorganic sulfur compounds (RISCs), global transcriptional analysis was used to track the response of specific genes associated with these complexes, as well as other known and putative respiratory electron transport chain elements. ORFs from all five terminal oxidase or bc1-like complexes were stimulated on one or more conditions tested. Components of the fox (Msed0467-0489) and soxNL-cbsABA (Msed0500-0505) terminal/quinol oxidase clusters were triggered by ferrous iron, while the soxABCDD' terminal oxidase cluster (Msed0285-0291) were induced by tetrathionate and S°. Chemolithotrophic electron transport elements, including a putative tetrathionate hydrolase (Msed0804), a novel polysulfide/sulfur/DMSO reductase-like complex (Msed0812-0818), and a novel heterodisulfide reductase-like complex (Msed1542-1550), were also stimulated by RISCs. Furthermore, several hypothetical proteins were found to have strong responses to ferrous iron or RISCs, suggesting additional candidates in iron or sulfur oxidation-related pathways. From this analysis, a comprehensive model for electron transport in M. sedula could be proposed as the basis for examining specific details of iron and sulfur oxidation in this bioleaching archaeon.
Project description:transcriptomic study of the impact of iron toxicity on rice plant (Oryza sativa L.; cv M-bM-^@M-^XI Kong PaoM-bM-^@M-^Y ) after short term (3 days) or long term (3 weeks) exposure to ferrous iron (125 ppm). Twenty five days old rice seedlings were exposed to 0 or 125 mg/L ferrous iron for 3 days and 3 weeks in hydroponic culture. Comparison between control and iron stressed plants were done at the shoot and the root levels. The assays were replicated twice on two independent plant cultures. 8 samples, Two-condition experiment, control (0 ppm ferrous iron) vs. iron treated (125 ppm ferrous iron). Biological replicates: 2 replicates for comparison shoot 3 days of stress, root 3 days of stress, shoot 3 weeks of stress and root 3 weeks of stress.
Project description:Abstract: The crenarchaeal order Sulfolobales collectively contains at least five major terminal oxidase complexes. Based on genome sequence information, all five complexes are found only in Metallosphaera sedula and Sulfolobus tokodaii, the two sequenced Sulfolobales capable of iron oxidization. While specific respiratory complexes in certain Sulfolobales have been characterized previously as proton pumps for maintaining intracellular pH and generating proton motive force (pmf), their contribution to sulfur and iron biooxidation has not been considered. For M. sedula growing in the presence of ferrous iron and reduced inorganic sulfur compounds (RISCs), global transcriptional analysis was used to track the response of specific genes associated with these complexes, as well as other known and putative respiratory electron transport chain elements. ORFs from all five terminal oxidase or bc1-like complexes were stimulated on one or more conditions tested. Components of the fox (Msed0467-0489) and soxNL-cbsABA (Msed0500-0505) terminal/quinol oxidase clusters were triggered by ferrous iron, while the soxABCDD' terminal oxidase cluster (Msed0285-0291) were induced by tetrathionate and S°. Chemolithotrophic electron transport elements, including a putative tetrathionate hydrolase (Msed0804), a novel polysulfide/sulfur/DMSO reductase-like complex (Msed0812-0818), and a novel heterodisulfide reductase-like complex (Msed1542-1550), were also stimulated by RISCs. Furthermore, several hypothetical proteins were found to have strong responses to ferrous iron or RISCs, suggesting additional candidates in iron or sulfur oxidation-related pathways. From this analysis, a comprehensive model for electron transport in M. sedula could be proposed as the basis for examining specific details of iron and sulfur oxidation in this bioleaching archaeon. 5-slide loop of Mse cells includes 5 conditions tested: yeast exact (Y), yeast extract + ferrous sulfate (YFS), yeast extract + potassium sulfate (YKS), yeast extract + potassium tetrathionate (YKT), and yeast extract + elemental sulfur (YS). Half of an RNA sample for one condition was labeled with Cy3 while the other half was labeled with Cy5. The two differently labeled samples were run on different slides. Each probe is spotted on each slide 5 times (5 replicates; spot intensities for all replicates on slide provided in associated raw data file).
Project description:We explored the transcriptome change of Streptococcus suis in the presence of ferrous iron and cobalt by RNA sequencing. The data revealed that expression of a lot of genes was altered to respond to ferrous iron and cobalt toxicity. Moreover, most of the genes differentially expressed in response to cobalt are the same as those in response to ferrous iron.
Project description:transcriptomic study of the impact of iron toxicity on rice plant (Oryza sativa L.; cv ‘I Kong Pao’ ) after short term (3 days) or long term (3 weeks) exposure to ferrous iron (125 ppm). Twenty five days old rice seedlings were exposed to 0 or 125 mg/L ferrous iron for 3 days and 3 weeks in hydroponic culture. Comparison between control and iron stressed plants were done at the shoot and the root levels. The assays were replicated twice on two independent plant cultures.
Project description:In this study we show that cAMP helps regulate cytosine demethylation through augmenting the intracellular labile ferrous iron pool.
Project description:The two-component system qseBC is a putative prokaryotic adrenergic receptor. In Aggregatibacter actinomycetemcomitans (Aa), it was shown that the qseBC responds significantly to the presence of both catecholamines and ferrous iron. In addition, growth is significantly increased in the presence of both. Therefore, we performed a custom Aa microarray in order to determine the effects of catecholamines and catecholamines and iron (CAT-Fe) on Aa. Aggregatibacter actinomycetemcomitans was grown in triplicate in a chemically defined media (CDM) supplemented with either 100uM of ferrous chloride or 50uM of norepinephrine or both. At mid-log, RNA was harvested using the Qiagen Lipid Tissue Minikit.
Project description:The two-component system qseBC is a putative prokaryotic adrenergic receptor. In Aggregatibacter actinomycetemcomitans (Aa), it was shown that the qseBC responds significantly to the presence of both catecholamines and ferrous iron. In addition, growth is significantly increased in the presence of both. Therefore, we performed a custom Aa microarray in order to determine the effects of catecholamines and catecholamines and iron (CAT-Fe) on Aa.
Project description:Iron is the fourth most abundant element in the Earth’s crust. However, the poor solubility of iron due to oxidation of ferrous iron to the almost insoluble ferric iron under aerobic conditions constitutes a considerable challenge for living organisms to obtain sufficient amounts of the iron available. In the present study, we set out to characterize the global gene expression of C. glutamicum under iron limitation in comparison to iron-replete conditions.