Siderophores of Marinobacter aquaeolei: petrobactin and its sulfonated derivatives

Homann, Vanessa V.; Edwards, Katrina J.; Webb, Eric A.; Butler, Alison

doi:10.1007/s10534-009-9237-0

Cited by 45 publications

(36 citation statements)

References 32 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…To our knowledge, ABC transporters of sulfonated siderophores have not been characterized. However, members of the Marinobacter genus have been shown to synthesize a sulfonated siderophore (36,37). It is possible that CD2992-2989 has specificity for a sulfonated derivative of a siderophore.…”

Section: Discussionmentioning

confidence: 99%

Ferric Uptake Regulator Fur Control of Putative Iron Acquisition Systems in Clostridium difficile

Ellermeier

2015

J Bacteriol

View full text Add to dashboard Cite

Clostridium difficile is an anaerobic, Gram-positive, spore-forming opportunistic pathogen and is the most common cause of hospital-acquired infectious diarrhea. Although iron acquisition in the host is a key to survival of bacterial pathogens, high levels of intracellular iron can increase oxidative damage. Therefore, expression of iron acquisition mechanisms is tightly controlled by transcriptional regulators. We identified a C. difficile homologue of the master bacterial iron regulator Fur. Using targetron mutagenesis, we generated a fur insertion mutant of C. difficile. To identify the genes regulated by Fur in C. difficile, we used microarray analysis to compare transcriptional differences between the fur mutant and the wild type when grown in highiron medium. The fur mutant had increased expression of greater than 70 transcriptional units. Using quantitative reverse transcriptase PCR (qRT-PCR), we analyzed several of the Fur-regulated genes identified by the microarray and verified that they are both iron and Fur regulated in C. difficile. Among those Fur-and iron-repressed genes were C. difficile genes encoding 7 putative cation transport systems of different classes. We found that Fur was able to bind the DNA upstream of three Fur-repressed genes in electrophoretic mobility shift assays. We also demonstrate that expression of Fur-regulated putative iron acquisition systems was increased during C. difficile infection using the hamster model. Our data suggest that C. difficile expresses multiple iron transport mechanisms in response iron depletion in vitro and in vivo. IMPORTANCEClostridium difficile is the most common cause of hospital-acquired infectious diarrhea and has been recently classified as an "urgent" antibiotic resistance threat by the CDC. To survive and cause disease, most bacterial pathogens must acquire the essential enzymatic cofactor iron. While import of adequate iron is essential for most bacterial growth, excess intracellular iron can lead to extensive oxidative damage. Thus, bacteria must regulate iron import to maintain iron homeostasis. We demonstrate here that C. difficile regulates expression of several putative iron acquisition systems using the transcriptional regulator Fur. These import mechanisms are induced under iron-limiting conditions in vitro and during C. difficile infection of the host. This suggests that during a C. difficile infection, iron availability is limited in vivo.A lmost all living organisms require iron as a cofactor for essential metabolic chemistry (1). Although iron is one of the most abundant of Earth's elements, ferric iron has very limited solubility in aqueous, nonacidic, or oxygenated environments (1). Ferric iron is most often found as iron oxides or hydroxides, which cannot be used by most organisms. Competition over bioavailable iron is fierce both among bacteria in complex microbial communities and between bacterial pathogens and their eukaryotic hosts (2).Organisms have evolved various mechanisms of iron transport to obtain this essentia...

show abstract

Section: Discussionmentioning

confidence: 99%

Ferric Uptake Regulator Fur Control of Putative Iron Acquisition Systems in Clostridium difficile

Ellermeier

2015

J Bacteriol

View full text Add to dashboard Cite

show abstract

“…A Chrome Azurol S assay showed that both Phaeobacter strains excrete siderophores under iron-limiting conditions, whereas Roseobacter denitrificans, which lacks the gene cluster, shows no excretion (Figure 4). The organization of the gene cluster is identical to that of the asbABCDEF petrobactin biosynthesis locus of Bacillus anthracis and Marinobacter aquaeoeli VT8 (Pfleger et al, 2007;Homann et al, 2009). The only difference is that asbC and asbD are fused in P. gallaeciensis (Figure 4).…”

Section: Geis Prophages and Gene-transfer Agents (Gtas)mentioning

confidence: 98%

Phaeobacter gallaeciensis genomes from globally opposite locations reveal high similarity of adaptation to surface life

et al. 2012

View full text Add to dashboard Cite

Phaeobacter gallaeciensis, a member of the abundant marine Roseobacter clade, is known to be an effective colonizer of biotic and abiotic marine surfaces. Production of the antibiotic tropodithietic acid (TDA) makes P. gallaeciensis a strong antagonist of many bacteria, including fish and mollusc pathogens. In addition to TDA, several other secondary metabolites are produced, allowing the mutualistic bacterium to also act as an opportunistic pathogen. Here we provide the manually annotated genome sequences of the P. gallaeciensis strains DSM 17395 and 2.10, isolated at the Atlantic coast of north western Spain and near Sydney, Australia, respectively. Despite their isolation sites from the two different hemispheres, the genome comparison demonstrated a surprisingly high level of synteny (only 3% nucleotide dissimilarity and 88% and 93% shared genes). Minor differences in the genomes result from horizontal gene transfer and phage infection. Comparison of the P. gallaeciensis genomes with those of other roseobacters revealed unique genomic traits, including the production of iron-scavenging siderophores. Experiments supported the predicted capacity of both strains to grow on various algal osmolytes. Transposon mutagenesis was used to expand the current knowledge on the TDA biosynthesis pathway in strain DSM 17395. This first comparative genomic analysis of finished genomes of two closely related strains belonging to one species of the Roseobacter clade revealed features that provide competitive advantages and facilitate surface attachment and interaction with eukaryotic hosts.

show abstract

“…In comparison, the iron-reducing Shewanella oneidensis MR-1 has 66 cytochromes (1.46% of the proteincoding genes), 13 of which are predicted to function as (per)oxidases in the outer membrane and potentially as extracellular proteins. Marine amphiphilic siderophores involved in the acquisition of iron have previously been isolated from VT8 (27). The genome of VT8 harbors several candidate genes with a potential function in iron acquisition via siderophores, uptake through permeases, and redox activity.…”

Section: Acquisition Of Carbonmentioning

confidence: 99%

Genomic Potential of Marinobacter aquaeolei, a Biogeochemical “Opportunitroph”

Singer

Webb

Nelson

et al. 2011

Appl Environ Microbiol

Self Cite

113

109

View full text Add to dashboard Cite

The genus of Marinobacter is one of the most ubiquitous in the global oceans and assumed to significantly impact various biogeochemical cycles. The genome structure and content of Marinobacter aquaeolei VT8 was analyzed and compared with those from other organisms with diverse adaptive strategies. Here, we report the many "opportunitrophic" genetic characteristics and strategies that M. aquaeolei has adopted to promote survival under various environmental conditions. Genome analysis revealed its metabolic potential to utilize oxygen and nitrate as terminal electron acceptors, iron as an electron donor, and urea, phosphonate, and various hydrocarbons as alternative N, P, and C sources, respectively. Miscellaneous sensory and defense mechanisms, apparently acquired via horizontal gene transfer, are involved in the perception of environmental fluctuations and antibiotic, phage, toxin, and heavy metal resistance, enabling survival under adverse conditions, such as oil-polluted water. Multiple putative integrases, transposases, and plasmids appear to have introduced additional metabolic potential, such as phosphonate degradation. The genomic potential of M. aquaeolei and its similarity to other opportunitrophs are consistent with its cosmopolitan occurrence in diverse environments and highly variable lifestyles.

show abstract

Siderophores of Marinobacter aquaeolei: petrobactin and its sulfonated derivatives

Cited by 45 publications

References 32 publications

Ferric Uptake Regulator Fur Control of Putative Iron Acquisition Systems in Clostridium difficile

Ferric Uptake Regulator Fur Control of Putative Iron Acquisition Systems in Clostridium difficile

Phaeobacter gallaeciensis genomes from globally opposite locations reveal high similarity of adaptation to surface life

Genomic Potential of Marinobacter aquaeolei, a Biogeochemical “Opportunitroph”

Contact Info

Product

Resources

About