Neuropeptides are small molecules that mediate intercellular signaling and regulate physiological processes. Starfish possess various myoactive neuropeptides, including starfish myorelaxant peptide (SMP) and a calcitonin-type peptide with apical muscle relaxing properties. In this study, we report the purification of a neuropeptide from starfish (Patiria pectinifera) pyloric caeca extract using high-performance liquid chromatography (HPLC) and an in vitro bioassay to screen for fractions and peptides with relaxing effects on P.
View Article and Find Full Text PDFMarine organisms, such as sea urchins like Heliocidaris crassispina, produce bioactive substances with antimicrobial activity to protect themselves from the high density of microorganisms in their habitats. One such substance, Echinochrome A (Ech A), has been isolated from various sea urchins' shells and spines using strong acidic solutions and organic solvents. Ech A, however, has not been reported from the coelomic fluid of H.
View Article and Find Full Text PDFAquatic freshwater fish like catfish, Silurus asotus, lives in microbe-rich environments, which enable this fish to develop necessary defense mechanisms. Antimicrobial peptides, along with other innate immune factors, are regarded as an important group in this defense. An antimicrobial peptide, which was isolated from the skin of S.
View Article and Find Full Text PDFFish skin mucus is considered to act as the first line of defense against waterborne pathogens and to be potential source of novel antimicrobial components. Here we report the purification and characterization of a novel hepcidin type 2-like antimicrobial peptide (TpHAMP2) from the skin mucus of the pufferfish Takifugu pardalis. The purified TpHAMP2 comprised of 23 amino acids (AAs) with eight Cys residues that form four intramolecular disulfide bonds.
View Article and Find Full Text PDFCalcitonin (CT) is a peptide hormone released by the thyroid gland that regulates blood Ca levels in mammals. The CT gene is alternatively spliced, with one transcript encoding CT and another transcript encoding the CT-like neuropeptide calcitonin-gene related peptide (α-CGRP), which is a powerful vasodilator. Other CT-related peptides in vertebrates include adrenomedullin, amylin, and intermedin, which also act as smooth muscle relaxants.
View Article and Find Full Text PDFInvertebrates, unlike vertebrates which have adaptive immune system, rely heavily on the innate immune system for the defense against pathogenic bacteria. Lysozymes, along with other immune effectors, are regarded as an important group in this defense. An invertebrate-type (i-type) lysozyme, designated Urechis unicinctus invertebrate-type lysozyme, Uu-ilys, has been isolated from nephridia of Urechis unicinctus using a series of high performance liquid chromatography (HPLC), and ultrasensitive radial diffusion assay (URDA) as a bioassay system.
View Article and Find Full Text PDFDev Comp Immunol
September 2018
Antimicrobial peptides (AMPs) are components of innate immunity found in many forms of life. However, there have been no reports of AMPs in sea star (Phylum Echinodermata). Here we report the isolation and characterization of a novel antimicrobial peptide from the coelomic epithelium extract of the sea star Patiria pectinifera.
View Article and Find Full Text PDFPedal peptides and orcokinins are structurally related neuropeptides that were first discovered in protostomian invertebrates - mollusks and arthropods, respectively. Recently, pedal peptide/ocokinin (PP/OK)-type neuropeptides were discovered in a deuterostomian phylum, the echinoderms, indicating that the evolutionary origin of this neuropeptide family can be traced back to the common ancestor of bilaterian animals. Sequences comparison of PP/OK-type neuropeptides reveals several conserved residues, including N- and C-terminally located hydrophobic residues that are important for the bioactivity of orcokinin.
View Article and Find Full Text PDFStarfish (Phylum Echinodermata) are of interest from an evolutionary perspective because as deuterostomian invertebrates they occupy an "intermediate" phylogenetic position with respect to chordates (e.g. vertebrates) and protostomian invertebrates (e.
View Article and Find Full Text PDFRecent studies suggest that vertebrate and invertebrate defensins have evolved from two independent ancestors, and that both defensins could share origins with animal toxins. Here, we purified novel sea anemone neurotoxin (BDS)-like antimicrobial peptides (AMPs)-Crassicorin-I and its putative homolog (Crassicorin-II)-from the pharynx extract of an anthozoan sea anemone (Urticina crassicornis). Based on structural analyses and cDNA cloning, mature Crassicorin-I represents a cationic AMP likely generated from a precursor and comprising 40 amino acid residues, including six cysteines forming three intramolecular disulfide bonds.
View Article and Find Full Text PDFA ∼1.7 kDa antimicrobial peptide was purified from the acidified body extract of the Lugworm, Marphysa sanguinea, by preparative acid-urea-polyacrylamide gel electrophoresis and C18 reversed-phase high performance liquid chromatography (HPLC). The identified peptide is composed of 14 amino acids with the N-terminal acetylation.
View Article and Find Full Text PDFInhibition of angiogenesis has been focused on as a strategy for treating several diseases including cancer. In this study, a novel model peptide αAL14 was synthesized and used to identify its inhibitory effects on angiogenesis. The anti-angiogenic effects of αAL14 were investigated using vascular endothelial cells, HUVECs.
View Article and Find Full Text PDFA bioactive peptide mimicking peptide-signaling molecules has been isolated from the skin extract of fish Channa argus which caused contraction of the apical muscle of a starfish Patiria pectinifera, a deuterostomian invertebrate. The primary structure of the isolated pentapeptide comprises amino acid sequence of H-Pro-Ala-Leu-Ala-Leu-OH (PALAL) with a molecular mass of 483.7 Da.
View Article and Find Full Text PDFA 4.7 kDa antimicrobial peptide was purified from the acidified gill extract of the Abalone, Haliotis discus, by cation-exchange and C18 reversed-phase high performance liquid chromatography (HPLC). Comparison of the amino acid sequences and molecular weight of this peptide with those of other known antimicrobial peptides revealed that this antimicrobial peptide have high sequence homology with that of cgMolluscidin and was designated hdMolluscidin.
View Article and Find Full Text PDFNeuropeptides that act as muscle relaxants have been identified in chordates and protostomian invertebrates but little is known about the molecular identity of neuropeptides that act as muscle relaxants in deuterostomian invertebrates (e.g. echinoderms) that are 'evolutionary intermediates' of chordates and protostomes.
View Article and Find Full Text PDFThe central nervous system (CNS) of Aplysia is a fascinating source to identify and characterize neuropeptides and neurotransmitters because of offering many useful divergent and convergent neuronal aggregates. Here, two neuropeptides were isolated from the extract of CNS of the northwest pacific sea hare, Aplysia kurodai, using HPLC system for fractionation and the anterior byssus retractor muscle (ABRM) of the Mytilis edulis as the bioassay system. Purified peptides, myomodulin A (MMA) and E (MME), were determined by amino acid sequencing and molecular mass analysis.
View Article and Find Full Text PDFA 2.3 kDa of antimicrobial peptide was purified from an acidified liver extract of skipjack tuna, Katsuwonus pelamis, by preparative acid-urea-polyacrylamide gel electrophoresis and C18 reversed-phase HPLC. A comparison of the amino acid sequence of the purified peptide with those of other known polypeptides revealed high homology with the C-terminus of hemoglobin β-chain; thus, this peptide was designated as the Skipjack Hemoglobin β chain-related Antimicrobial Peptide (SHβAP).
View Article and Find Full Text PDFA 3.4 kDa of antimicrobial peptide was purified from an acidified skin extract of skipjack tuna, Katsuwonus pelamis, by preparative acid-urea-polyacrylamide gel electrophoresis and C18 reversed-phase HPLC. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high sequence homology with the YFGAP (Yellowfin tuna Glyceraldehyde-3-phosphate dehydrogenase-related Antimicrobial Peptide); thus, this peptide was identified as the skipjack tuna GAPDH-related antimicrobial peptide (SJGAP).
View Article and Find Full Text PDFAppl Biochem Biotechnol
February 2013
Cathepsin X, also known as cathepsin Z, is referred to as a "lysosomal proteolytic enzyme" and a member of the peptidase C1 family, which is involved in various biological processes such as immune response, cell adhesion, and proliferation. In the present study, the cDNA of starfish (Asterina pectinifera), which is known to cause serious damage to commercial shellfish mariculture, cathepsin X (ApCtX) was isolated through the combination of homology molecular cloning and rapid amplification of cDNA ends (RACE) methods for the application to find a way to reduce/control starfish densities. The full-length of ApCtX gene was determined to consist of the 2,240 bp nucleotide sequence, which encoded for a preproprotein of 296 amino acids with a molecular mass of about 32.
View Article and Find Full Text PDFTo determine the role of cathepsin L in Echinoderms, starfish (Asterina pectinifera) cathepsin L (ApCtL) was cloned. The results of RT-PCR analysis indicated that the expression of ApCtL in all of the tissues. The pro-mature enzyme of ApCtL, proApCtL, was expressed in Escherichia coli, and cathepsin activity was detected by cleaving of synthetic fluorogenic peptide substrates and gelatin zymography.
View Article and Find Full Text PDFAn antimicrobial polypeptide was purified from an acidified gill extract of Pacific oyster (Crassostrea gigas) by C(18) reversed-phase HPLC. The purified polypeptide had a molecular weight of 8471Da containing 74 amino acid residues. Comparison of the obtained N-terminal sequences with those of others revealed that it was identical to ubiquitin reported from other species and named cgUbiquitin.
View Article and Find Full Text PDFA 3.4 kDa of antimicrobial peptide was purified from an acidified skin extract of the yellowfin tuna, Thunnus albacares, by preparative acid-urea-polyacrylamide gel electrophoresis and C(18) reversed-phase HPLC. A comparison of the N-terminal amino acid sequence of the purified peptide with that of other known polypeptides revealed high homology with the N-terminus of glyceraldehyde-3-phosphate dehydrogenase (GAPDH); thus, this peptide was designated as the yellowfin tuna GAPDH-related antimicrobial peptide (YFGAP).
View Article and Find Full Text PDFAn approximately 21 kDa antimicrobial protein was purified from an acidified testis extract of olive flounder, Paralichthys olivaceus, by ion-exchange and C(18) reversed-phase HPLC. A comparison of the N-terminal amino acid sequence with those of other known antimicrobial polypeptides revealed high homology between this antimicrobial protein and other histone H1 molecules; thus, it was designated flounder histone H1-like protein (fH1LP). fH1LP showed potent antimicrobial activity against Gram-positive bacteria, including Bacillus subtilis, Staphylococcus aureus, and Streptococcus iniae (minimal effective concentrations [MECs], 2.
View Article and Find Full Text PDFA new bioactive tetradecapeptide, GFKDNVSNRIAHGFamide, was isolated from the brain of the squid, Todarodes pacificus. Using isolated T. pacificus esophagus as a bioassay, the peptide was shown to induce potent contraction of smooth muscle.
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