Work

Establishing genetic tractability in Jeongeupia sacculi HS-3: disruption of rpoS hinders biofilm formation

Year: 2026

Type: preprint

Abstract: Jeongeupia sacculi (HS-3) is a novel β -proteobacterium with a unique multicellular life cycle. The genetic tractability and mechanisms underlying differentiation are unknown. Here, we adapt a method of homologous recombination for genetic modification in HS-3 and generate a disruption mutant of rpoS , which encodes the alternative sigma factor σ S commonly associated with general stress response or major behavioral switches. We then characterize phenotypes associated with rpoS disruption. Under low-nutrient conditions, rpoS disruption reduced Congo red binding, consistent with rpoS acting as a regulator of low-nutrient response by upregulating production of biofilm-associated materials. Surprisingly, rpoS disruption did not significantly alter survival in response to other stressors in general stress response assays tested. Our work establishes a method for genetic manipulation in HS-3 and enables future investigation into the life cycle of HS-3, including whether rpoS has a role in differentiation triggered by low-nutrient response.

Source: bioRxiv (Cold Spring Harbor Laboratory)

DOI: 10.64898/2026.10.09.758012

Authors: Zachary Beddingfield, Isabel Calimlim, Christopher Zhang, Brian K Hammer

Institution: Georgia Institute of Technology

Language: English

Topic: Bacterial Genetics and Biotechnology

Subfield: Genetics

Field: Biochemistry, Genetics and Molecular Biology

Domain: Life Sciences

Open Access status: green

Funders: U.S. Department of Education, Georgia Institute of Technology, Directorate for Biological Sciences

Award: G4539520696