Penaeidins, a New Family of Antimicrobial Peptides Isolated from the Shrimp Penaeus vannamei (Decapoda)

Abstract

We report here the isolation of three members of a new family of antimicrobial peptides from the hemolymph of shrimps Penaeus vannamei in which immune response has not been experimentally induced. The three molecules display antimicrobial activity against fungi and bacteria with a predominant activity against Gram-positive bacteria. The complete sequences of these peptides were determined by a combination of enzymatic cleavages, Edman degradation, mass spectrometry, and cDNA cloning using a hemocyte cDNA library. The mature molecules (50 and 62 residues) are characterized by an NH 2 -terminal domain rich in proline residues and a COOH-terminal domain containing three intramolecular disulfide bridges. One of these molecules is post-translationally modified by a pyroglutamic acid at the first position. Comparison of the data obtained from the cDNA clones and mass spectrometry showed that two of these peptides are probably COOHterminally amidated by elimination of a glycine residue. These molecules with no evident homology to other hitherto described antimicrobial peptides were named penaeidins.

SNPs of hemocyanin C‐terminal fragment in shrimp Litopenaeus vannamei

“…Carcinolectin 5 (CL5) from Carcinoscorpius rotundicauda can produce two isoforms (CL5a and CL5b) that recognize and differentiate between bacteria and fungi [27]. Penaeidin in penaeid shrimp have five classes, in which penaeidin-3 has antifungal and antibacterial activities, while penaeidin-5 possesses antiviral properties [28,29]. Consistent with the above observations, our results showed that some SNP sites in the hemocyanin C-terminus were involved in the resistance of L. vannamei towards various pathogens (Fig.…”

Adaptive evolution after duplication of penaeidin antimicrobial peptides

“…It is possible that since these mature peptides (PRD and CRD) are used to protect against the pathogens and filamentous fungal species [13,28], their adaptive evolution will be caused by several factors. Like MHC receptors, immunoglobulins, defensins and AMPs [36,57,64e66], penaeidin may be under selection directed by the evolution of pathogens.…”

“…A total of 36 nucleotide sequences were retrieved from GenBank ( [6,7,11,13,16,18,22,24,25]; Table 1). Sequences were aligned using DAMBE version 4.5.2 [38,39] and BioEdit version 7.0.5.3 [40].…”

“…Penaeidins are the diverse family of cationic peptides [28] and are classified into four classes (PEN-2, PEN-3, PEN-4 and PEN-5) [7,8,10,12,13,15e 20,22,24,25]. Penaeidin consists of two distinct active domains: a proline-rich N-terminal domain (PRD) and cysteine-rich C-terminal domains (CRD) that inhibit the growth of several gram-positive bacterial and filamentous fungal species [13,28]. Multiple isoforms produced by amino acid substitutions and deletions within the PRD and CRD have been reported at the mRNA level for three classes of penaeidins suggesting that this is a highly diverse gene family [22].…”

Molecular insight into mechanism of antimicrobial action of the β‐hairpin peptide arenicin: Specific oligomerization in detergent micelles

“…Invertebrate animals, living without adaptive immunity in a microbe laden environment, produce AMPs as important evolutionary conserved component of their innate immune system, which play a key role in the host defense against bacterial, fungal, and viral invasion. 1,2 In marine invertebrates, a battery of AMPs were found in Spongia, Cnidaria, Annelida, Mollusca, Chelicerata, Crustacea, and Tunicata, for example, aurelin from jellyfish, 3 myticin from mussels, 4 tachyplesins and polyphemusins from horseshoe crabs, 5,6 penaeidins from shrimp, 7 clavanins and styelins from ascidians. [8][9][10] Earlier we discovered two novel 21-residue AMPs, termed arenicins, from coelomocytes of marine polychaeta lugworm Arenicola marina.…”