Judith P. Sinn

Judith P. Sinn

  • Assistant Research Professor
320 Buckhout Lab (office)
307 Buckhout Lab (lab)

University Park, PA 16802

Areas of Expertise

  • Molecular biology
  • Plant bacteriology
  • Development of novel controls for citrus greening and fire blight
  • Genetics of virulence and auxotrophy in Erwinia amylovora


  • B.S., Environmental Resource Management, Penn State
  • M.S., Plant Pathology, Penn State

Program Interests

As Senior Research Assistant in Dr. Tim McNellis' lab, my research focuses on host and pathogen genes and proteins involved in bacterial disease processes. We employ molecular and genetic tools to elucidate mechanisms contributing to host susceptibility and pathogen virulence.  Current work includes mutational studies with Erwinia amylovoraPantoea ananatis, and Xanthomonas campestris pv pelargoniia, causal agents of fire blight of pome fruits, center rot of onion, and bacterial blight of geranium, respectively, and a project involving citrus greening disease (huánglóngbìng), caused by Candidatus Liberibacter.


Virulence genetics of an erwinia amylovora putative polysaccharide transporter family member
Journal of bacteriology, Klee, Sara M., Sinn, Judith P., Christian, Elena, Holmes, Aleah C., Zhao, Kaixi, Lehman, Brian L., Peter, Kari A., Rosa, Cristina, McNellis, Timothy W., 2020

Flowering locus t chimeric protein induces floral precocity in edible citrus
Plant Biotechnology Journal, Sinn, Judith P., Held, Jeremy B., Vosburg, Chad, Klee, Sara M., Orbovic, Vladimir, Taylor, Earl L., Gottwald, Tim R., Stover, Ed, Moore, Gloria A., McNellis, Timothy W., 2020

Erwinia amylovora auxotrophic mutant exometabolomics and virulence on apples
Applied and environmental microbiology, Klee, Sara M., Sinn, Judith Pawloski, Finley, Melissa, Allman, Erik L., Smith, Philip B., Aimufua, Osaretin, Sitther, Viji, Lehman, Brian L., Krawczyk, Teresa, Peter, Kari Anne, McNellis, Timothy W., 2019

Extragenic suppression of elongation factor P gene mutant phenotypes in erwinia amylovora
Journal of bacteriology, Klee, Sara M., Sinn, Judith P., Holmes, Aleah C., Lehman, Brian L., Krawczyk, Teresa, Peter, Kari A., McNellis, Timothy W., 2019

An Erwinia amylovora yjeK mutant exhibits reduced virulence, increased chemical sensitivity and numerous environmentally dependent proteomic alterations
Molecular plant pathology, Klee, Sara M., Mostafa, Islam, Chen, Sixue, Dufresne, Craig, Lehman, brian L., Sinn, Judith Pawloski, Peter, Kari Anne, McNellis, Timothy W., 2018

Erwinia amylovora pyrC mutant causes fire blight despite pyrimidine auxotrophy
Letters in Applied Microbiology, Ramos, L. S., Sinn, Judith Pawloski, Lehman, B. L., Pfeufer, E. E., Peter, Kari Anne, McNellis, Timothy W., 2015

The fire blight pathogen Erwinia amylovora requires the rpoN gene for pathogenicity in apple
Molecular Plant Pathology, Ramos, Laura S., Lehman, Brian L., Sinn, Judith Pawloski, Pfeufer, Emily E., Halbrendt, Noemi O., McNellis, Timothy W., 2013