Hemoglobins, key components of our blood, are ancient proteins with well-known roles in oxygen transport and respiration in animals. Hemoglobins are also present in plants and bacteria, but until now the physiological role of plant hemoglobins has been unclear. A group of researchers reveal this week that one such mysterious plant hemoglobin serves to assist in the fixation of nitrogen in the root nodules of legumes through a process that is conceptually not unlike that undertaken by mammalian hemoglobins in facilitating oxygen transport and exchange in the blood.
The most conspicuous plant hemoglobins are the symbiotic hemoglobins of legumes; these hemoglobins accumulate in root nodules and give these specialized organs their distinctive red color. Legume root nodules accommodate bacteria, called rhizobia, that reduce atmospheric nitrogen to ammonia, which is subsequently used by the plant for growth and colonization of nitrogen-poor soils. Symbiotic nitrogen fixation is important for sustainable agriculture and contributes millions of tons of reduced nitrogen to crops and pastures each year.
As reported this week, researchers led by Dr. Michael Udvardi at the Max Planck Institute of Molecular Plant Physiology have succeeded in eliminating the production of symbiotic hemoglobins in nodules of the model legume Lotus japonicus, enabling researchers to assess for the first time the role and importance of these proteins in plants. The results of the study indicate that symbiotic hemoglobins are important for oxygen transport and energy metabolism in plant root nodules. Furthermore, these proteins help to maintain free-oxygen concentrations in nodules at levels low enough to avoid damage of oxygen-sensitive nitrogenase, the bacterial enzyme complex responsible for symbiotic nitrogen fixation. Thus, plant hemoglobins fulfill roles analogous to those of animal hemoglobins, as well as novel roles that are apparently unique to symbiotic nitrogen fixation.
Staying in Shape
16.08.2018 | Max-Planck-Institut für molekulare Zellbiologie und Genetik
Chips, light and coding moves the front line in beating bacteria
16.08.2018 | Okinawa Institute of Science and Technology (OIST) Graduate University
Scientists at the University of California, Los Angeles present new research on a curious cosmic phenomenon known as "whistlers" -- very low frequency packets...
Scientists develop first tool to use machine learning methods to compute flow around interactively designable 3D objects. Tool will be presented at this year’s prestigious SIGGRAPH conference.
When engineers or designers want to test the aerodynamic properties of the newly designed shape of a car, airplane, or other object, they would normally model...
Researchers from TU Graz and their industry partners have unveiled a world first: the prototype of a robot-controlled, high-speed combined charging system (CCS) for electric vehicles that enables series charging of cars in various parking positions.
Global demand for electric vehicles is forecast to rise sharply: by 2025, the number of new vehicle registrations is expected to reach 25 million per year....
Proteins must be folded correctly to fulfill their molecular functions in cells. Molecular assistants called chaperones help proteins exploit their inbuilt folding potential and reach the correct three-dimensional structure. Researchers at the Max Planck Institute of Biochemistry (MPIB) have demonstrated that actin, the most abundant protein in higher developed cells, does not have the inbuilt potential to fold and instead requires special assistance to fold into its active state. The chaperone TRiC uses a previously undescribed mechanism to perform actin folding. The study was recently published in the journal Cell.
Actin is the most abundant protein in highly developed cells and has diverse functions in processes like cell stabilization, cell division and muscle...
Scientists have discovered that the electrical resistance of a copper-oxide compound depends on the magnetic field in a very unusual way -- a finding that could help direct the search for materials that can perfectly conduct electricity at room temperatur
What happens when really powerful magnets--capable of producing magnetic fields nearly two million times stronger than Earth's--are applied to materials that...
08.08.2018 | Event News
27.07.2018 | Event News
25.07.2018 | Event News
16.08.2018 | Life Sciences
16.08.2018 | Earth Sciences
16.08.2018 | Life Sciences