By Amber Friedrichsen
Samuel Shobade, graduate student in biochemistry, is the recipient of the inaugural 2023 Dhamu and Kanchana Thamodaran Innovation in Agriculture Student Award.
This award was established to support undergraduate and graduate students in the College of Agriculture and Life Sciences who have innovative scientific, technological or business ideas for solving grand challenges in agriculture. The $3,000 scholarship is intended to be used to advance research methods, develop technology, and fund tuition and travel. Funding for the award comes from CALS alumnus Dhamu Thamodaran, who earned his doctoral degree in economics in 1983, as well as his wife, Kanchana.
Shobade is pursuing a doctorate in biochemistry. He earned a bachelor’s in biochemistry from Lagos State University in Nigeria, and a master’s in biochemistry from the University of Lagos College of Medicine.
His research at Iowa State involves the expression and detection of chitinases in the rhizosphere — the area of soil surrounding plant roots. Chitinase is an enzyme that breaks down the chitin in the cell walls of fungi and arthropods. Plant roots can detect the presence of these pathogens in the soil and produce protective molecules, like chitinases, to defend themselves.
“If the plant is producing more chitinases than usual, we know something is wrong in the soil environment,” Shobade said. “My goal is to reduce the damage done to crops each year from microorganism attacks.”
Shobade spent several months characterizing plant chitinases with his principal investigator, Marit Nilsen-Hamilton, professor of biochemistry, biophysics and molecular biology. He then used a method called Systematic Evolution of Ligands by Exponential Enrichment (SELEX) to identify aptamers — short sequences of nucleic acids — that would bind to the chitinases. After binding, these chitinases can then be detected in soil samples using a biosensor that is functionalized with the selected aptamer.
“For example, people who have diabetes use glucose strips to test their blood and determine if their blood glucose level is higher than normal,” Shobade said. “When we test a sample of soil close to the roots with a biosensor, we can determine if the production of chitinases is higher than normal.”
Shobade’s work is a part of a larger project in the Department of Biochemistry, Biophysics and Molecular Biology called the 4-D Analysis of Molecules by Aptamers in Soil, or 4-D MAPS. It is the first time root chitinases have been characterized and the first time aptamers that bind to them have been classified, and Shobade wanted to pursue this reserach because fungal pathogens can significantly affect food production and the economy, causing up to 10-20% of crop losses worldwide. After studying the structure and function of chitinases, he believes there are opportunities to use protein engineering to create biological fungicides that contain chitinases to reduce crop loss from disease.
Carmen Bain, associate dean for academic innovation, said the selection committee for the award agreed Shobade’s research was innovative and cutting-edge in its approach to enhance crop growth, crop yields and food quality.
“His work exemplifies our college’s belief that identifying and developing solutions to complex problems in agriculture requires interdisciplinary thinking and practice,” Bain said.
Shobade will use his award earnings to continue testing how well different aptamers bind to chitinases, and build a biosensor specifically designed to detect these aptamers, which he is currently designing with a team of engineers. He will also use the funds to attend professional conferences like the Interdisciplinary Biological Sciences Symposium at Iowa State to share his research with others.
In addition to the award’s financial support, Shobade appreciates being recognized for his accomplishments. “I feel a sense of encouragement that I am making a substantial contribution to something that people are going to benefit from,” he said.