Callinectin, an Antibacterial Peptide from Blue Crab, Callinectes sapidus, Hemocytes

This paper describes the isolation of an approximately 3.7 kDa, basic, antibacterial peptide (designated callinectin), which represents the major antibiotic activity in blue crab, Callinectes sapidus, hemocytes. A single-step purification using low-pressure cation-exchange chromatology yielded a highly purified (>95%) peptide. Purity was confirmed by C4 reverse-phase high-performance liquid chromatography (RP-HPLC), native gel electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), capillary electophoresis, and mass spectral analysis. The partial amino acid sequence obtained via Edman degradation revealed no significant homology to other reported peptides in the Basic Local Alignment Search Tool (BLAST) program database.