Novel Antimicrobial Peptide from the Hepatopancreas of the Red King Crab

Abstract

Crustaceans have successfully adapted to survive in their natural habitat, rich in microorganisms, due to the presence of antimicrobial peptides (AMPs) in their organism. They achieve this adaptation despite lacking the highly specific adaptive immune system found in vertebrates. One valuable source of AMPs is the hepatopancreas, a waste product from crab fishery and its processing. Applying zymographic and spectrophotometric techniques, we discovered a small peptide (approximately 5 kDa) within a low molecular weight protein fraction extracted from the acetone powder of the red king crab hepatopancreas. This peptide hydrolyzes both M. lysodeikticus cell wall and M. lysodeikticus cell wall polysaccharide, while showing no activity against gelatin. The found peptide may be of interest for application in medicine, biotechnology, and the food industry, for example as a bio-preservative.

The Blue Treasure: Comprehensive Biorefinery of Blue Crab (Callinectes sapidus)

“…To date, shellfish protein hydrolysates have principally been employed for the production of low-value livestock and fish feeds, flavours, and additives for food. However, several studies have evidenced that marine-derived protein hydrolysates and peptides, including crab waste, can be utilised as functional food ingredients in the prevention of cardiovascular disease (CVD), diabetes, cancer, and obesity-related chronic conditions [115][116][117], owing to their antioxidant, antihypertensive, anticoagulant calcium-binding, appetite-suppressant, and human immunodeficiency virus (HIV)-1 protease-inhibitory activities [118]. Like that in other crustaceans, the haemolymph in blue crab contains biologically active substances such as lectins, clotting factors, and antimicrobial peptides, which have been shown to have a primary role in the innate immune defence system of marine invertebrates [119].…”