Molecular Cloning and Recombinant Expression of Tiger Shrimp Penaeus monodon Penaeidin

Abstract

A penaeidin cDNA sequence of tiger shrimp Penaeus monodon was obtained. In the sequence, an open reading frame that coded for a peptide composed of 74 amino acids was found. A cleavage site of secretory signal peptide was predicted between amino acids 19 and 20. The calculated molecular mass of mature penaeidin was about 6.1 kDa and the estimated pl of this peptide was 9.1. Northern blot analysis indicated that the penaeidin was mainly synthesized in the hemocytes. Clustering analysis of penaeidin sequences from P. monodon, P. vannamei, P. setiferus, P. japonicus and P. chinensis was performed. The recombinant penaeidin was expressed using insect-baculovirus expression system. The recombinant penaeidin showed antimicrobial activity against a bacterium Aerococcus viridans, but not Vibrio alginolyticus, Vibrio harveyi or a yeast Debaryomyces hansenii. In addition, it delayed spore germination and growth of a filamentous fungus Neurospora crassa.