California Sea Grant College Program

Although the pharmaceutical industry has “mined” the world of soil bacteria, streptomycetes and fungi to find novel antimicrobial molecules, the emergence of resistant superbugs necessitates identifying new antibiotic sources. Recent research into the innate immune system has focused attention on antimicrobial peptides – molecules that equip animals to resist infection without assistance from antibodies and other accoutrements of adaptive immunity. In recent years, potent antimicrobial peptides have been identified in the blood cells (hemocytes) of horseshoe crabs, shrimp, mussels and tunicates ("sea squirts"). Our studies centered on three tunicates (Styela clava, Styela plicata and Ciona intestinalis) that are abundant in Southern California's shallow waters.