Preprint: undergraduate CURE screen identifies Bacillus isolates that suppress Ras/MAPK signalling in C. elegans

Researchers describe the WormFood CURE (Course-based Undergraduate Research Experience), a programme designed to integrate authentic scientific discovery into undergraduate teaching by screening environmental bacterial isolates for bioactive secondary metabolites. The functional readout used was suppression of the multivulva (Muv) phenotype in C. elegans — an established proxy for aberrant activation of the Ras/MAPK signalling pathway, which is a driver of proliferative disease across species.

A pilot cohort of students screened 41 wild bacterial isolates and identified two hits: a Bacillus safensis isolate (BAC-08) and a Bacillus altitudinis isolate (BAC-44), both of which significantly inhibited ectopic vulval precursor cell induction in the worm assay. The identity of the active metabolites and their mechanism of Ras pathway antagonism are not characterised in the preprint; the screen represents a first-pass phenotypic discovery step.

From a genetics-education standpoint, the paper illustrates how the well-characterised C. elegans Ras pathway can serve as a scalable, accessible platform for student-led functional genomics and chemical biology research. The Ras signalling pathway is of longstanding interest in cancer biology; however, this preprint reports an educational research exercise, not a therapeutic discovery, and the distance from environmental bacterial metabolite to any clinical application is considerable.

This work has not yet been peer-reviewed.