• Korean Journal of Fisheries and Aquatic Sciences
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• v.54 no.6
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• pp.927-937
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• 2021

This study was performed to screen the antimicrobial activities of the extract from the Pacific oyster Crassostrea gigas against skin pathogens and to purify the relevant antibacterial peptide. The acidified extract showed potent antibacterial activities against gram-positive and gram-negative bacteria but showed no activity against Candida albicans and no significant cell toxicity. Among acne-causing pathogens, the acidified extract showed potent antibacterial activity only against Staphylococcus aureus, and its antibacterial activity was completely abolished by treatment with trypsin or chymotrypsin, and was inhibited by salt treatment. The acidified extract showed strong DNA-binding ability but did not show bacterial membrane permeabilizing ability. Based on antimicrobial activity screening and cytotoxic effects, a novel antibacterial peptide was purified from the acidified gill extract using solid-phase extraction, cation-exchange, and reversed-phase HPLC. The resulting peptide had a molecular weight of 4800.8 Da and showed partial sequence homology with the carbonic anhydrase 4 (CA4) protein in the hard-shelled mussel. Overall, we purified a novel antibacterial peptide, named cgCAFLP, which is related to carbonic anhydrase 4 (CA4) protein, against skin pathogens. Our results suggest that the Pacific oyster extract could be used as an additive to control some acne-related skin pathogens (S. aureus).