Synchrotron science could give soybeans a boost

April 11, 2018

Scientists at the University of Liverpool, together with Japanese colleagues, have gained new insight into how soil bacteria sense and adapt to the levels of oxygen in their environment. The findings could be used to help develop new treatments to promote crop growth and tackle disease.

Living organisms are sensitive to the changes of environmental factors, such as oxygen, light, and heat. To adapt to these changes, humans have signal transduction systems that sense each environmental factor and maintain our lives by responding to them. Such systems are present not only in humans but also in all living organisms, and each organism maintains its life by using its own systems.

In this study, an international collaborative research team led by Professor Samar Hasnain at the University's Institute of Integrative Biology and Dr Hitomi Sawai at the University of Hyogo, Japan focused on a protein system that senses the concentration of oxygen in the soil by the root nodule bacteria (rhizobia) that coexist with legumes.

Using the synchrotron radiation facilities 'SOLEIL' in France and 'SPring-8' in Japan the team has successfully elucidated the first overall structure of this system.

The results of this study are published in the scientific journal Science Signaling published by the American Association for the Advancement of Science (AAAS).

Root nodules occur on the roots of leguminous plants such as soybean and peas. The nodules associate with symbiotic bacteria known as rhizobia, which are responsible for an important reaction called 'nitrogen fixation' that converts nitrogen in the Earth's atmosphere into the ammonia, readily available for plants.

As this reaction cannot take place in the presence of oxygen, the rhizobia have a protein system that senses the oxygen concentration.

In this system, a protein that functions as an oxygen sensor is FixL, and a protein that controls the biosynthesis of nitrogen fixation enzymes in response to oxygen sensing by FixL is FixJ. The signal transduction system that consists of two kinds of proteins, such as the FixL/FixJ system, is called the 'two-component signal transduction system'.

Since the two-component signal transmission system does not exist in animals, it has gained increasing attraction as a development target of antimicrobial agents and plant growth promoters without side effects to animals.

However, despite more than 65,000 such systems being identified over the last 30 years, the whole structure of the sensing protein has not been elucidated in any system, making it difficult to fully understand how living organisms sense and adapt to environmental factors.

To develop this knowledge, the international research team used advanced biochemical and x-ray techniques to elucidate the overall structure of oxygen-sensing two-component FixL/FixJ proteins in rhizobia.

Professor Hasnain commented: "The FixL/FixJ protein of soybean nodule bacteria, which is the target of this research, is indispensable for the supply of nitrogen nutrients essential to the growth of soybean - a highly nutritious and useful plant.

"By using the information of the elucidated three-dimensional structure, it is possible to develop a new type of antibacterial agent that does not affect animals by making a drug that acts on and specifically inhibits the two-component signal transduction system."
-end-


University of Liverpool

Related Protein Articles from Brightsurf:

The protein dress of a neuron
New method marks proteins and reveals the receptors in which neurons are dressed

Memory protein
When UC Santa Barbara materials scientist Omar Saleh and graduate student Ian Morgan sought to understand the mechanical behaviors of disordered proteins in the lab, they expected that after being stretched, one particular model protein would snap back instantaneously, like a rubber band.

Diets high in protein, particularly plant protein, linked to lower risk of death
Diets high in protein, particularly plant protein, are associated with a lower risk of death from any cause, finds an analysis of the latest evidence published by The BMJ today.

A new understanding of protein movement
A team of UD engineers has uncovered the role of surface diffusion in protein transport, which could aid biopharmaceutical processing.

A new biotinylation enzyme for analyzing protein-protein interactions
Proteins play roles by interacting with various other proteins. Therefore, interaction analysis is an indispensable technique for studying the function of proteins.

Substituting the next-best protein
Children born with Duchenne muscular dystrophy have a mutation in the X-chromosome gene that would normally code for dystrophin, a protein that provides structural integrity to skeletal muscles.

A direct protein-to-protein binding couples cell survival to cell proliferation
The regulators of apoptosis watch over cell replication and the decision to enter the cell cycle.

A protein that controls inflammation
A study by the research team of Prof. Geert van Loo (VIB-UGent Center for Inflammation Research) has unraveled a critical molecular mechanism behind autoimmune and inflammatory diseases such as rheumatoid arthritis, Crohn's disease, and psoriasis.

Resurrecting ancient protein partners reveals origin of protein regulation
After reconstructing the ancient forms of two cellular proteins, scientists discovered the earliest known instance of a complex form of protein regulation.

Sensing protein wellbeing
The folding state of the proteins in live cells often reflect the cell's general health.

Read More: Protein News and Protein Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.