Crustins from eyestalk cDNA library of swimming crab Portunus trituberculatus: Molecular characterization, genomic organization and expression analysis

► Two Type I crustins were characterized from eyestalk of swimming crab. ► Three and two introns were identified in genomic DNA of PtCrustins, respectively. ► Their transcripts were mainly detected in eyestalk and gills. ► PtCrustins mRNA in hemocytes was up-regulated after three microorganisms challenge. ► Recombinant PtCrustins exhibited antimicrobial activity against bacteria and fungus.