Project description:To identify the mechanism of Microbial Influenced Corrosion (MIC) and the bacterial response toward corrosion, we conducted whole genome microarray expression profile. At log phase, the cell of Clostridium carboxidivorans using iron granule as an electron donor (corroding iron) was collected as a sample, and that of using syngas as an electron donor was collected as a control.
Project description:Transcriptional profiling analysis was used to reveral the genetic changes of B.subtilis after addition of high levels of iron. This study is to reveal the effect of high levels of iron on B.subtilis' metabolism and identify the potential resistance mechanism to high levels of iron. 1_1 is the independent biological replicate of sample 2_1, while sample 1_2 is the independent biological replicate of sample 2_2. Bacteria collected from each B.subtilis culture at 0min were mixed and used as ch2 source for each sample. The ch1 sources of sample 1_1 and 2_1 are bacteria collected from cultures without addition of Fe3+ at 20min, while the ch1 sources of sample 2_1 and 2_2 are bacteria collected from cultures with addition of 4mM Fe3+ at 20min.
Project description:Transcriptomic profiling of Pseudomonas fluorescens Pf-5 comparing iron(II) chloride supplemented grown culture against non-iron treated grown culture in M9 minimal media Two-condition experiment, iron(II) chloride supplemented culture versus non-iron treated culture. 4 biological replicates including 3 technical replicates for one of the biological replicates. Swap-dye experiments were performed
Project description:Elizabethkingia anophelis bacteria encounter fluxes of iron in the midgut of mosquitoes, where they live as symbionts. They also establish bacteremia with severe clinical manifestations in humans, and live in water service lines in hospitals. In this study, we investigated the global gene expression responses of E. anophelis to iron fluxes in the midgut of female Anopheles stephensi mosquitoes fed sucrose or blood, and in iron-poor or iron-rich culture conditions. Of 3,686 transcripts revealed by RNAseq technology, 218 were upregulated while 112 were down-regulated under iron-poor conditions. Most of these differentially expressed genes were enriched in functional groups assigned within “biological process,” “cell component” and “molecular function” categories. E. anophelis possessed 4 iron/heme acquisition systems. Hemolysin gene expression was significantly repressed when cells were grown under iron-rich or high temperature (37℃) conditions. Furthermore, hemolysin gene expression was down-regulated after a blood meal, indicating that E. anophelis cells responded to excess iron and its associated physiological stress by limiting iron loading. By contrast, genes encoding respiratory chain proteins were up-regulated under iron-rich conditions, allowing these iron-containing proteins to chelate intracellular free iron. In vivo studies showed that growth of E. anophelis cells increased 3-fold in blood-fed mosquitoes over those in sucrose-fed ones. Deletion of aerobactin synthesis genes led to impaired cell growth in both iron-rich and iron-poor media. Mutants showed more susceptibility to H2O2 toxicity and less biofilm formation than did wild-type cells. Mosquitoes with E. anophelis experimentally colonized in their guts produced more eggs than did those treated with erythromycin or left unmanipulated, as controls. Results reveal that E. anophelis bacteria respond to varying iron concentration in the mosquito gut, harvest iron while fending off iron-associated stress, contribute to lysis of red blood cells, and positively influence mosquito host fecundity.
Project description:Iron is an essential micronutrient for all living organisms, and sequestering of iron and the virulence of pathogenic bacteria are believed to be correlated. As the defense mechanisms, potential hosts therefore keep the level of free iron inside the body to a minimum. The iron metabolism is well studied in general for several pathogens of humans and animals, but it is still mostly unclear how gene expression levels change in pathogens during the initial stages of infections. In this work, using Aliivibrio salmonicida we studied the immediate changes in transcription levels in response to a sudden decrease in iron levels. Microarray technology was used to monitor global changes in transcriptional levels. Cultures of A. salmonicida were grown to mid log phase before the iron chelator 2,2’-dipyridyl was added and samples were collected after 15 minutes of growth. Using our statistical cut-off values, we retrieved thirty-two differentially expressed genes where the most up-regulated genes belong to an operon encoding proteins responsible for producing the siderophore bisucaberin.
Project description:Non-targeted metabolomics of culture extracts of altermonas. Samples were extracted with PPL SPE and measured by DDA-MS/MS including native ESI experiments with post-column iron addition.
Project description:Transcriptomic profiling of Pseudomonas fluorescens Pf-5 comparing iron(III) chloride supplemented grown culture against non-iron treated grown culture in M9 minimal media Two-condition experiment, iron(III) chloride supplemented culture versus non-iron treated culture. 3 biological replicates including 3 technical replicates for one of the biological replicate and 2 technical replicates for another biological replicate. Swap-dye experiments were performed