Recombinant Macaca mulatta Coagulation factor XI (Active)

Factor XI occupies a critical node in the intrinsic coagulation pathway, and this full-length mature protein (aa 19–624) demonstrates robust catalytic function with a specific activity exceeding 150 pmol/min/µg against the fluorogenic substrate Boc-IEGR-AMC, providing a quantitative foundation for kinetic parameter analysis including Km, Vmax, and kcat/Km determination. The protein exhibits an EC50 of 0.5654–0.6444 ng/mL in antibody-binding ELISA, confirming proper folding and epitope accessibility that supports its use as a positive control in immunoassays and as a reference standard in inhibitor screening campaigns aimed at identifying anticoagulant drug candidates. Dual purity verification by SDS-PAGE and SEC-HPLC (both >95%), combined with endotoxin levels below 1.0 EU/µg, meets the quality thresholds commonly required for accurate IC50 determination and substrate specificity profiling where contaminants would confound enzymatic measurements. The C-terminal His tag preserves active-site integrity, enabling structure-function studies and mechanism-of-action investigations in cardiovascular research models.