Recombinant Escherichia coli Uncharacterized protein YcbX (ycbX) (Active)

YcbX remains a largely uncharacterized E. coli protein whose functional interactions are only beginning to be mapped, making validated binding reagents essential for exploratory studies. This full-length recombinant YcbX (aa 1–369), expressed in *E. coli* with an N-terminal GST tag, has demonstrated measurable interaction with immobilized LdcC in a functional ELISA, yielding an EC50 range of approximately 359–628 μg/ml — providing a quantitative baseline for researchers investigating novel protein-protein interactions in *E. coli* K12. The confirmed binding activity supports use in ELISA-based interaction screening, pull-down assays leveraging the GST tag, and development of functional binding controls for characterizing the LdcC–YcbX axis. Purity exceeding 85% by SDS-PAGE aligns with standards expected in protein interaction studies, though researchers planning cell-based assays should note that endotoxin levels have not been tested and may require additional assessment.