HOME >> BIOLOGY >> NEWS
Researchers discover hemoglobin's enzymatic nature

lobin delivers oxygen and nitric oxide to tissues," said Stamler. According to the new data, however, the nematode hemoglobin uses nitric oxide to trigger an enzymatic reaction that actually consumes oxygen. These data suggest that the primary role of the nematode's hemoglobin is to destroy oxygen. This would make sense, Stamler explained, because the Ascaris parasite has a low tolerance for oxygen. "The worms can deal with oxygen, but they don't really like it," he said.

Even in low-oxygen environments such as the human intestine, where the worms live, oxygen molecules do seep in. These must be neutralized, which the worm's hemoglobin does by grabbing and consuming oxygen molecules in a unique enzymatic reaction driven by nitric oxide.

Using spectroscopic techniques, the scientists studied how the nematode hemoglobin acts in the presence of different concentrations of oxygen and hemoglobin. The results of these experiments led the researchers to propose that Ascaris destroys oxygen via a 10-step chemical reaction.

The key to this process, says Stamler, lies with the exact positioning of a single sulfur-containing amino acid within the oxygen-binding pocket of the nematode's hemoglobin. "If this amino acid is on one side of the pocket, the hemoglobin uses nitric oxide to destroy oxygen. If it's on the other side of the pocket, as it is in mammalian hemoglobin, nitric oxide acts as a regulator of oxygen delivery," explained Stamler.

The discovery places Ascaris hemoglobin at a unique evolutionary juncture between primitive hemoglobins that evolved in the first living creatures on the planet--when the Earth's atmosphere was composed mostly of nitric oxide--and modern hemoglobin found in mammals and birds.

"In the primordial atmosphere, nitric oxide came before oxygen," Stamler said. "It was probably there before any life form, and the first bacteria needed a way to protect themselves from nitric oxide." Nitric
'"/>

Contact: Jim Keeley
keeleyj@hhmi.org
301-215-8858
Howard Hughes Medical Institute
30-Sep-1999


Page: 1 2 3 4

Related biology news :

1. Researchers determine genetic cause of Timothy syndrome
2. Researchers find color sensitive atomic switch in bacteria
3. Researchers identify protein promoting vascular tumor growth
4. Researchers devise potent new tools to curb ivory poaching
5. Researchers create nanotubes that change colors, form nanocarpet and kill bacteria
6. Researchers ID chlorophyll-regulating gene
7. Researchers develop fast track way to discover how cells are regulated
8. Researchers identify distinctive signature for metastatic prostate cancer
9. Researchers report new gene test for isolated cleft lip and palate
10. Researchers discover why mutant gene causes colon cancer
11. Researchers identify the genomes controlling elements

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:11/17/2016)... Calif. , Nov. 17, 2016  AIC announces that it has just released ... in organizations that require high-performance scale-out plus high speed data transfer storage solutions. ... ... ... Setting up a high ...
(Date:11/14/2016)... -- xG Technology, Inc. ("xG" or the "Company") (Nasdaq: XGTI, ... use in challenging operating environments, announced its results for ... hold a conference call to discuss these results on ... below). Key Recent Accomplishments ... to acquire Vislink Communication Systems. The purchase is expected ...
(Date:6/22/2016)... , June 22, 2016   ... management and verification solutions, has partnered with ... software solutions for Visitor Management, Self-Service Kiosks ... provides products that add functional enhancements to ... provides corporations and venues with an automated ...
Breaking Biology News(10 mins):
(Date:12/5/2016)... 2016 According to the ... Products (Consumable, Instruments, Automated Cell Expansion System), Cells ... Cell Research, Cancer, and Cell-Based Research), End-users (Biopharmaceutical ... Global Revenue, Trends, Growth, Share, Size and Forecast ... global cell expansion market is expected to reach ...
(Date:12/5/2016)... MDx announced today that it brought its NxGen Informed Prenatal Test in-house. ... improve customer service through shortened turnaround times and at the same time ... NxGen MDx. ... A decrease in turnaround times by 25% combined with ... the Grand Rapid headquarters. The NxGen Informed Prenatal Test uses ...
(Date:12/5/2016)... 2016 The U.S. Biotechnology industry ... billion of revenue and some $890 billion of total ... global biopharmaceuticals, and this figure is expected to exceed ... up these four equities for assessment: Northwest Biotherapeutics Inc. ... ACAD ), Acorda Therapeutics Inc. (NASDAQ: ...
(Date:12/4/2016)...  In five studies being presented today during the ... Exposition in San Diego , researchers ... delivery of life-saving treatments to patients with a variety ... carry therapies directly to the sites in the body ... substantial advantage over traditional, systemic methods. The studies highlight ...
Breaking Biology Technology:
Cached News: