PRECS 2019

Construction of a Tn5 mutant library in Xanthomonas cucurbitae

Keirsten Kline, Hagerstown Community College
Rikky Rai, University of Illinois at Urbana-Champaign
Sarah R. Hind, University of Illinois at Urbana-Champaign

Financial support was provided by the National Science Foundation under grant #NSF REU 1559908/1559929, as part of the Phenotypic Plasticity Research Experience for Community College Students, through the University of Illinois at Urbana-Champaign Institute for Genomic Biology and Parkland College.

This project was completed with the cooperation of Dr. Hinds's Laboratory,, Department of Crop Sciences, University of Illinois at Urbana-Champaign.


The health and yield of important crop plants around the world is a significant concern when faced with food scarcity in the generations to come. The Xanthomonas bacterial genus can infect more than 400 different plant species including economically important crops such as rice and soy. In Illinois, Xanthomonas cucurbitae can infect pumpkin and winter squash and cause bacterial spot disease (Figure 1) resulting in up to 100% yield loss of pumpkin crops. The disease caused by this pathogen has become one of the most significant threats to production of pumpkins in Illinois, the U.S. and the world.

There are several known virulence factors in the Xanthomonas genus that induce pathogenic response in host plants. These include the hypersensitive response and pathogenicity (hrp) gene cluster and quorum-sensing (QS) pathways. Much of the genome of X. cucurbitae, however, is unknown. We aim to identify and understand the function of novel virulence genes in the X. cucurbitae genome by generating a transposonmediated mutant library and analyzing mutants for genes involved in QS response and hrp activity by using a reporter plasmid to allow for screening of the transposon’s effects.