Navigation Links
Bacteria hijack plentiful iron supply source to flourish
Date:7/9/2014

In an era of increasing concern about the prevalence of antibiotic-resistant illness, Case Western Reserve researchers have identified a promising new pathway to disabling disease: blocking bacteria's access to iron in the body.

The scientists showed how bacterial siderophore, a small molecule, captures iron from two abundant supply sources to fan bacterial growth as well as how the body launches a chemical counterassault against this infection process. Their findings appear in a recent edition of The Journal of Experimental Medicine.

"Bacterial siderophore will be an important target for therapeutics one day because it can be modified to prevent bacteria from acquiring iron, but at the same time, it's possible to preserve host access to iron," said senior author Laxminarayana Devireddy, DVM, PhD, assistant professor of pathology, Case Comprehensive Cancer Center.

Investigators knew from the outset that bacterial siderophore captures iron from the host mammal and transforms it so that bacteria can absorb and metabolize the mineral. In this investigation, Devireddy and his colleagues discovered that human mitochondria, which very closely resemble bacteria, possess their own iron-acquisition machinery mitochondrial siderophore. Mammalian mitochondria are membrane-encased subunits within cells that generate most of the cell's energy, and like their bacteria counterparts, mammalian mitochondria have their own siderophore mechanism that seeks out, captures and delivers iron for utilization.

At the test tube level, investigators found that bacteria can feed on iron supplied by bacterial siderophore and mitochondrial siderophore. From this glut of iron, bacteria proliferate and make the host mammal very ill with an infection.

"It's like bacteria can use their own iron-capture machinery or the host's. It just doesn't matter," Devireddy said. "They are very good at utilizing siderophore from both bacterial and mammalian siderophore sources. That means that bacteria get the most iron."

Case Western Reserve researchers also demonstrated that the absence of mitochondrial siderophore in a mammal can enhance its ability to resist infection. When investigators exposed mice deficient for mitochondrial siderophore to systemic infection by E. coli, the animals resisted infection. The reason? E. coli bacteria had less iron to access from mitochondrial siderophore-deficient mice.

Additionally, mammals are not entirely defenseless from a bacteria raid on mitochondrial siderophore iron supplies. In another phase of their investigation, scientists found that normal mice secrete the protein lipocalin 24p3, which isolates bacterial siderophore and suppresses synthesis of mammalian siderophore.

"The action of lipocalin significantly reduced the mortality of the mice from the E. coli infection, and some mice actually recovered," Devireddy said. "That kind of delay in bacterial proliferation gave the immune system time to identify and then neutralize the microbe."

These findings highlight the potential of developing effective therapeutics to reverse bacterial infection.

"Any approach that would suppress either bacterial or mitochondrial siderophore and activate lipocalin-2 would likely slow infection, allowing the host's immune system to respond," Devireddy said. "Such novel approaches would also provide a much-needed alternative to treat those infections that have become antibiotics resistant."


'/>"/>

Contact: Jeannette Spalding
jeannette.spalding@case.edu
216-368-3004
Case Western Reserve University
Source:Eurekalert

Related biology news :

1. Leading evolutionary scientist to discuss how genome of bacteria has evolved
2. Study by UC Santa Barbara researchers suggests that bacteria communicate by touch
3. Team discovers how bacteria resist a Trojan horse antibiotic
4. From scourge to saint: E. coli bacteria becomes a factory - to make cheaper, faster pharmaceuticals
5. Bacterial shock to recapture essential phosphate
6. Disarming disease-causing bacteria
7. Study shows unified process of evolution in bacteria and sexual eukaryotes
8. Invisible helpers: How probiotic bacteria protect against inflammatory bowel diseases
9. Researchers develop rapid test strips for bacterial contamination in swimming water
10. Bacteria discovery could lead to antibiotics alternatives
11. Agricultural bacteria: Blowing in the wind
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/27/2016)... CHESTER, Ohio , Jan. 27, 2016  Rite ... supplier based in West Chester, Ohio ... their award winning service staff, based in ... technical capacity and ability to provide modifications, installations and ... John Dovalina , CEO of PLUS, commented, "PLUS has ...
(Date:1/25/2016)... , Jan. 25, 2016  Glencoe Software, the ... pharma and publication industries, will provide the data management ... Centre (NPSC). ... Phenotypic analysis measures ... whole organisms, allowing comparisons between states such as health ...
(Date:1/22/2016)... DUBLIN , Jan. 22, 2016 /PRNewswire/ ... announced the addition of the "Global ... report to their offering. --> ... of the "Global Biometrics Market in ... offering. --> Research and ...
Breaking Biology News(10 mins):
(Date:2/10/2016)... ... February 10, 2016 , ... ... states, announced today the promotion of two long-standing principal investigators (PI) to the ... Medicine, Clinical Research and Development. , Dr. Laurence Chu, a Benchmark Research PI ...
(Date:2/10/2016)... Latham, NY (PRWEB) , ... February 10, 2016 , ... ... photodiode packages at the SPIE Photonics West conference in San Francisco’s Moscone ... and 14 in the same venue. , These latest InGaAs PIN diode standard ...
(Date:2/10/2016)... , ... February 10, 2016 , ... ... (PROMPT), a research registry built on the secure online PatientCrossroads platform, has exceeded ... than 1,600 participants have joined the PROMPT study, which seeks to advance understanding ...
(Date:2/10/2016)... ... February 10, 2016 , ... ... has announced a new agreement with Singapore-based Global Stem Cells Network (GSCN) and ... Philippines, Thailand and Singapore in the latest adipose and bone marrow therapies. ...
Breaking Biology Technology: