Location: Cereal Crops ResearchTitle: Natural variations in extracellular protease impact virulence in bacterial leaf streak of barley caused by Xanthomonas translucens
|ALAOFIN, SEFUNMI - North Dakota State University|
|VELASCO, DIEL - North Dakota State University|
|LIU, ZHAOHUI - North Dakota State University|
|BALDWIN, THOMAS - North Dakota State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 4/11/2023
Publication Date: 7/18/2023
Citation: Alaofin, S., Velasco, D., Li, D., Liu, Z., Baldwin, T., Schachterle, J.K. 2023. Natural variations in extracellular protease impact virulence in bacterial leaf streak of barley caused by Xanthomonas translucens. Meeting Abstract. 19:324.
Technical Abstract: Bacterial leaf streak of barley is an emerging problem worldwide and is caused by Xanthomonas translucens. In order to better understand the virulence mechanisms used by this pathogen, we screened several isolates for production of secreted extracellular enzymes. We found that some isolates, including strain B1 from North Dakota, USA, lack extracellular protease activity. Strain B1 also has lower virulence on barley than strains that exhibit protease activity. Genomic analysis revealed a 16 amino acid deletion in the protease gene in isolates lacking protease activity, including strain B1. The same deletion was found in genomes of isolates from North Dakota and Iran. We cloned the protease from protease positive strains and functionally complemented the protease deficient strains, restoring visible activity when grown on skim milk agar. Virulence of strain B1 was significantly increased by introducing a functional copy of the protease gene on a plasmid. Together, our result indicate that extracellular protease contributes to virulence of Xanthomonas translucens, but that a subset of environmentally occurring isolates share an in-frame deletion rendering the protease non-functional.