Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Recognizing pathogenic invaders

24.10.2011
Elucidation of the structure of receptors that detect invading pathogens in moths could aid the diagnosis of infectious fungal diseases

Researchers in Japan have determined the structural basis of the molecular defense system that protects insects from pathogens, which provides clarity on the molecular binding that underpins this defense system.

Insects express pattern recognition receptors (PRRs) that provide an innate ability to detect fungi and plant pathogens. One of the PRRs, â-glucan recognition protein (âGRP), recognizes and binds to carbohydrate molecules called â-glucans that are synthesized by pathogens. Since little is known about how these molecules bind to each other, or about how the binding specificity is achieved, Yoshiki Yamaguchi of the RIKEN Advanced Science Institute and his colleagues used genetic engineering to produce the â-glucan-binding regions of âGRPs from two moth species, Bombix mori and Plodia interpunctella. They determined the structure of the receptors, both on their own and when bound to a â-glucan called laminarihexaose, using x-ray crystallography.

Analysis of the crystal structures revealed that the moth receptors recognize a complex of three laminarihexaoses bound to each other, and that their conformation barely changes when they are bound to laminarihexaoses. The analysis also revealed that the proteins from both species bind to laminarihexaoses in an identical way, via a characteristic structural motif, suggesting that the entire âGRP family shares a common binding mechanism.

Yamaguchi and colleagues also revealed that the laminarihexaose molecules attach to each other with hydrogen bonds that form an ordered and highly stable helical structure. Six precisely arranged monosaccharide (sugar) residues, spread across three chains, interact with the receptor binding site simultaneously, and are essential for the interaction.

To verify their findings, the researchers introduced point mutations at specific locations in the binding region of the Plodia interpunctella receptor. Four of the mutations abolished binding of â-glucan altogether, and four others weakened the binding interaction.

Typically, interactions between carbohydrates and proteins are relatively weak because they involve just two or three monosaccharide residues. The finding that the interaction between the receptors and â-glucan involves six residues explains why this interaction is so strong; it also explains the high specificity of the receptors.

Mammals do not produce â-glucans, but they circulate in the bloodstream of patients with diseases such as invasive aspergillosis, a rapidly progressive and often fatal fungal infection.

“Our findings will be used for the development of diagnosis and monitoring tools with high specificity toward a variety of â-glucans,” says Yamaguchi. “Detecting â-glucans in patients may be helpful for identifying infectious fungi, which could in turn be useful to tailor-make treatments for patients.”

The corresponding author for this highlight is based at the Structural Glycolobiology Team, RIKEN Advanced Science Institute

Reference:
Kanagawa, M., Satoh, T., Ikeda, A., Adachi, Y., Ohno, N. & Yamaguchi, Y. Structural insights into recognition of triple-helical â-glucan by insect fungal receptor. Journal of Biological Chemistry 286, 29158–29165 (2011).

gro-pr | Research asia research news
Further information:
http://www.riken.jp
http://www.researchsea.com

More articles from Life Sciences:

nachricht New type of photosynthesis discovered
17.06.2018 | Imperial College London

nachricht New ID pictures of conducting polymers discover a surprise ABBA fan
17.06.2018 | University of Warwick

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: AchemAsia 2019 will take place in Shanghai

Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.

Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...

Im Focus: First real-time test of Li-Fi utilization for the industrial Internet of Things

The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.

Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.

Im Focus: Sharp images with flexible fibers

An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.

Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...

Im Focus: Photoexcited graphene puzzle solved

A boost for graphene-based light detectors

Light detection and control lies at the heart of many modern device applications, such as smartphone cameras. Using graphene as a light-sensitive material for...

Im Focus: Water is not the same as water

Water molecules exist in two different forms with almost identical physical properties. For the first time, researchers have succeeded in separating the two forms to show that they can exhibit different chemical reactivities. These results were reported by researchers from the University of Basel and their colleagues in Hamburg in the scientific journal Nature Communications.

From a chemical perspective, water is a molecule in which a single oxygen atom is linked to two hydrogen atoms. It is less well known that water exists in two...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Munich conference on asteroid detection, tracking and defense

13.06.2018 | Event News

2nd International Baltic Earth Conference in Denmark: “The Baltic Sea region in Transition”

08.06.2018 | Event News

ISEKI_Food 2018: Conference with Holistic View of Food Production

05.06.2018 | Event News

 
Latest News

A sprinkle of platinum nanoparticles onto graphene makes brain probes more sensitive

15.06.2018 | Materials Sciences

100 % Organic Farming in Bhutan – a Realistic Target?

15.06.2018 | Ecology, The Environment and Conservation

Perovskite-silicon solar cell research collaboration hits 25.2% efficiency

15.06.2018 | Power and Electrical Engineering

VideoLinks
Science & Research
Overview of more VideoLinks >>>