OpgD Enzyme for Anti-Bacterial Pesticides

‌Introduction

As climate change ravages the planet, food insecurity is on the rise in many underdeveloped and developing nations. Plant diseases, if left unchecked, can rapidly wipe out entire crop fields leaving both farmers and the local economy devastated. Therefore, it is pivotal that pathogens can be effectively eradicated through identification and removal before catastrophe strikes. 

About Xanthomonas 

One such pathogen is the Xanthomonas bacterial species. About twenty-seven subspecies of this bacterium is pathogenic to around four hundred plant species including staple crops such as sugar cane, beans, cassava, cabbage, banana, citrus, tomatoes, pepper and rice. The Xanthomonas species operates in two phases: epiphytic and endophytic. In the epiphytic stage it colonizes the surface of the plant using adhesion ligands and emits a biofilm to protect the bacteria from environmental stress factors. Then, in the endophytic stage, through the stomata it makes its way to the vascular system, spreading throughout the plant. Current management practices raise concerns of ineffectiveness, environmental pesticide contamination, and antibiotic resistance problems. 

The OpgD enzyme’s role

A pivotal function of the Xanthomonas species is its utilization of α-1,6-cyclized β-1,2-glucohexadecaose (CβG16α) to suppress plant-defense mechanisms. In a recent breakthrough, a team of researchers led by Associate Professor Masahiro Nakajima from Tokyo University of Science found that XccOpgD, a glycoside hydrolase (GH186) found in X. campestris pv campestris plays a pivotal role in the biosynthesis of CβG16α. Using X-ray crystallography, they discovered the enzyme’s specific catalytic mechanisms and substrate specificity. Particularly, XccOpgD uses an anomer-inverting transglycosylation mechanism. These insights are crucial in understanding structure-based drug targets as OpgD increases plant-resistence to disease while preventing environmental impacts of chemical-based pesticides.

Thus, this discovery leads mankind one step closer to addressing global sustainability challenges as a whole.

Citations

“Breakthrough in Plant Disease: New Enzyme Could Lead to Anti-Bacterial Pesticides.” ScienceDaily, www.sciencedaily.com/releases/2024/08/240801121853.htm. Accessed 3 Aug. 2024.

 “New Enzyme Could Lead to Anti-Bacterial Pesticides.” Food Manufacturing, 2024, www.foodmanufacturing.com/safety/news/22916562/new-enzyme-could-lead-to-antibacterial-pesticides. Accessed 3 Aug. 2024.

Nakayinga, Ritah, et al. “Xanthomonas Bacteriophages: A Review of Their Biology and Biocontrol Applications in Agriculture.” BMC Microbiology, vol. 21, no. 1, 25 Oct. 2021, https://doi.org/10.1186/s12866-021-02351-7. Accessed 9 Nov. 2021.

Ebrahim Osdaghi. “Xanthomonas Euvesicatoria Pv. Perforans (Bacterial Spot of Tomato).” CABI Compendium, 7 Jan. 2022, https://doi.org/10.1079/cabicompendium.108936. Accessed 3 Aug. 2024.