| protochordate immunity--ii. diverse hemolymph lectins in the solitary tunicate styela clava. | hemolymph lectins (agglutinins) of the tunicate styela clava were analyzed by agglutination, cross-absorption and carbohydrate-hemagglutination inhibition using several vertebrate erythrocytes. lectin activity was heat labile, dependent on divalent cations and refractory to neuraminidase-treated erythrocytes. four lectins with different carbohydrate specificities were found. carbohydrate specificities included l-rhamnose, d-glucuronolactone, maltose, d-galactosamine, d-mannosamine, d-galactose, ... | 1984 | 6509918 |
| cdna cloning of three cecropin-like antimicrobial peptides (styelins) from the tunicate, styela clava. | we cloned precursors of three new antimicrobial peptides, styelins c, d and e, from a pharyngeal cdna library of a tunicate, styela clava. preprostyelins resembled dipteran preprocecropins, while the mature domain of styelin c resembled cecropin p1, an antimicrobial peptide purified from the porcine intestine. beginning with the last 6 residues of their signal sequences, styelin c and cecropin 1 from drosophila virilis had 8/11 identical amino acids (72.7%). moreover, 4 of the last 6 residues of ... | 1997 | 9257708 |
| styelins, broad-spectrum antimicrobial peptides from the solitary tunicate, styela clava. | two novel phenylalanine-rich antimicrobial peptides, styelin a and styelin b, were purified from the hemocytes of styela clava. the peptides had very similar masses (styelin a, 3685.8; styelin b, 3700.6) and amino acid compositions, and at least 17 of their first 20 n-terminal residues were identical. both styelins were effective against a panel of gram negative and gram positive bacterial pathogens of humans, usually acting with minimal inhibitory concentrations < 1.5 microgram/ml (< 0.5 microm ... | 1997 | 9467865 |
| purification and characterization of a humoral opsonin from the solitary urochordate styela clava. | 1. we have previously identified opsonic activity in the plasma of the solitary urochordate, styela clava. 2. here, we report the purification and further characterization of the opsonic molecule. 3. two purification methods were employed. 4. gel filtration yielded one strongly opsonic fraction that contained a single, electrophoretically-resolved protein. 5. opsonic activity was dose-dependent and sensitive to tryptic digestion and heat denaturation. 6. sds-page and calibrated gel filtration in ... | 1992 | 1458848 |
| clavanins, alpha-helical antimicrobial peptides from tunicate hemocytes. | hemocytes from the invertebrate styela clava, a solitary tunicate, contained a family of four alpha-helical antimicrobial peptides that were purified, sequenced and named clavanins a, b, c and d. each clavanin contained 23 amino acid residues and was c-terminally amidated. the tunicate peptides resembled magainins in size, primary sequence and antibacterial activity. synthetic clavanin a was prepared and displayed comparable antimicrobial activity to magainins and cecropins. the presence of alph ... | 1997 | 9001389 |
| pcna mrna has a 3'utr antisense to yellow crescent rna and is localized in ascidian eggs and embryos. | the myoplasm is a localized cytoplasmic region that is involved in axis determination, gastrulation, muscle cell specification, and the pattern of cell divisions during ascidian development. the noncoding yellow crescent (yc) rna is localized in the myoplasm, but the function of this transcript is unknown. probes containing the 3' region of yc rna hybridize to other rnas in ascidian eggs. a cdna library from the ascidian styela clava was screened with a yc probe to identify maternal yc-related r ... | 1996 | 8812106 |
| a humoral opsonin from the solitary urochordate styela clava. | opsonins play a key role in invertebrate humoral immune systems. an opsonin for yeast was identified in the plasma of the tunicate, styela clava. in vitro cultures of hemocytes with homologous plasma-incubated yeast exhibited significantly higher levels of phagocytosis than controls. studies indicated that the opsonic activity of styela clava plasma increased the overall capacity for phagocytosis. opsonization was inhibited by the carbohydrates mannan, n-acetyl-d-galactosamine, and galactose, an ... | 1993 | 8449249 |
| clavanin bacterial sepsis control using a novel methacrylate nanocarrier. | controlling human pathogenic bacteria is a worldwide problem due to increasing bacterial resistance. this has prompted a number of studies investigating peptides isolated from marine animals as a possible alternative for control of human pathogen infections. clavanins are antimicrobial peptides isolated from the marine tunicate styela clava, showing 23 amino acid residues in length, cationic properties, and also high bactericidal activity. in spite of clear benefits from the use of peptides, cur ... | 2014 | 25382976 |
| clavanin a improves outcome of complications from different bacterial infections. | the rapid increase in the incidence of multidrug-resistant infections today has led to enormous interest in antimicrobial peptides (amps) as suitable compounds for developing unusual antibiotics. in this study, clavanin a, an antimicrobial peptide previously isolated from the marine tunicate styela clava, was selected as a purposeful molecule that could be used in controlling infection and further synthesized. clavanin a was in vitro evaluated against staphylococcus aureus and escherichia coli a ... | 2015 | 25547358 |
| exploration of the innate immune system of styela clava: zn(2+) binding enhances the antimicrobial activity of the tunicate peptide clavanin a. | tunicates have been used as primitive models for understanding cell-mediated and humoral immunity. clavanin a (clava) is one member of a family of antimicrobial peptides produced by the solitary tunicate styela clava. in this work, we demonstrate that clava utilizes zn(2+) ions to potentiate its antimicrobial activity not only by reducing the concentration at which the peptide inhibits the growth of bacteria but also by increasing the rate of killing. membrane depolarization, β-galactosidase lea ... | 2017 | 28226206 |
| natural peptide antibiotics from tunicates: structures, functions and potential uses. | because tunicates rely on innate immunity, their hemocytes are important contributors to host defense. styela clava, a solitary ascidian, have eight hemocyte subtypes. extracts of their total hemocyte population contained multiple small (2-4 kda) antimicrobial peptides. when purified, these fell into two distinct families that were named styelins and clavanins.styelins a-e are phenylalanine-rich, 32 residue peptides with activity against marine bacteria and human pathogens. they show considerabl ... | 2003 | 21680439 |
| fine- and regional-scale genetic structure of the exotic ascidian styela clava (tunicata) in southwest england, 50 years after its introduction. | styela clava, an ascidian native to the northwest pacific, was first recorded in the atlantic at plymouth, southwest england, in 1953. it now ranges in the northeast atlantic from portugal to northern denmark, and has colonized the east coast of north america. within the region of first introduction, we aimed to characterize current genetic diversity in the species, elucidate the respective roles of human-aided vs. natural dispersal, and assess the extent of larval dispersal by looking for genet ... | 2009 | 19161467 |
| chondroitin sulfate extracted from the styela clava tunic suppresses tnf-alpha-induced expression of inflammatory factors, vcam-1 and inos by blocking akt/nf-kappab signal in jb6 cells. | inflammatory mediators are known to play a key role in tumorigenesis, therefore, it is a promising strategy to inhibit the inflammation for cancer prevention and/or treatment. current study was performed to investigate the effects of chondroitin sulfate (cs) extracted from styela clava tunic on tnf-alpha-induced inflammation and to elucidate the mechanism of cs on the regulation of inflammatory factors in jb6 cells. our results showed that cs inhibited tnf-alpha-induced nf-kappab activation and ... | 2008 | 18295395 |
| trypanocidal and leishmanicidal activities of different antimicrobial peptides (amps) isolated from aquatic animals. | most of the available animal antimicrobial peptides (amps) have been tested against bacteria and fungi, but very few against protozoan parasites. in the present study, we investigated the antiparasitic activity of different amps isolated from aquatic animals: tachyplesin (tach, from tachypleus tridentatus), magainin (mag, from xenopus laevis), clavanin (clav, from styela clava), penaeidin (pen, from litopenaeus vannamei), mytilin (myt, from mytilus edulis) and anti-lipopolysaccharide factor (alf ... | 2008 | 17888907 |
| genetic distances in three ascidian species determined by pcr technique. | seven oligonucleotides primers were shown to generate the shared loci, specific loci, unique shared loci to each species and shared loci by the three species which could be obviously scored. in the present study, 7 oligonucleotides primers produced 401 total loci in the styela clava (sc) species, 390 in the halocynthia roretzi (hr) and 434 in the styela plicata (sp), respectively. seven oligonucleotides primers generated 275 specific loci in the sc, 341 in the hr and 364 in the sp species, respe ... | 2016 | 28144642 |
| labilibacter aurantiacus gen. nov., sp. nov., isolated from sea squirt (styela clava) and reclassification of saccharicrinis marinus as labilibacter marinus comb. nov. | a gram-stain-negative, facultatively anaerobic, orange-pigmented bacterium, designated hqyd1t, was isolated from a sea squirt (styelaclava) and characterized using a polyphasic approach. morphologically, strain hqyd1t exhibited rods with gliding motility. this novel isolate grew optimally at 28 °c in the presence of 2-3 % (w/v) nacl. the 16s rrna gene sequence was most similar to [saccharicrinis] marinus y11t (96.3 %), followed by saccharicinis fermentans dsm 9555t (93.8 %). the dominant fatty a ... | 2017 | 27902253 |
| styelin d, an extensively modified antimicrobial peptide from ascidian hemocytes. | we isolated styelin d, a 32-residue, c-terminally amidated antimicrobial peptide, from the blood cells (hemocytes) of the solitary ascidian, styela clava. styelin d had remarkably extensive post-translational modifications, containing two novel amino acids, dihydroxyarginine and dihydroxylysine, and two distinctly unusual ones, 6-bromotryptophan and 3,4-dihydroxyphenylalanine. in addition, the peptide exhibited microheterogeneity because of differential mono- and dihydroxylation of several lysin ... | 2000 | 10978343 |
| clavaspirin, an antibacterial and haemolytic peptide from styela clava. | we cloned the precursor of a novel peptide from a cdna library prepared from pharyngeal tissues of the tunicate, styela clava. its sequence predicted a histidine-rich, amidated 23-residue peptide (flrf(ig)svihgighlvhhigval-nh2) that we named clavaspirin. a synthetic clavaspirin was prepared and it was found that it killed gram-positive and gram-negative bacteria, permeabilized the outer and inner membranes of escherichia coli, lysed phosphatidylglycerol (popg) liposomes, and was potently haemoly ... | 2001 | 12005415 |
| effects of ph and salinity on the antimicrobial properties of clavanins. | clavanins are histidine-rich, amidated alpha-helical antimicrobial peptides that were originally isolated from the leukocytes (hemocytes) of a tunicate, styela clava. the activities of clavanin a amide and clavanin a acid against escherichia coli, listeria monocytogenes, and candida albicans were substantially greater at ph 5.5 than at ph 7.4. in contrast, clavanin ak, a synthetic variant of clavanin a acid containing 4 histidine-->lysine substitutions exerted substantial activity at both ph 7.4 ... | 1997 | 9199465 |
| draft genome sequence of streptomyces sp. avp053u2 isolated from styela clava, a tunicate collected in long island sound. | streptomyces sp. avp053u2 is a marine bacterium isolated from styela clava, a tunicate collected in long island sound. here, we report a draft genome for this bacterium, which was found to contain a high capacity for secondary metabolite production based on analysis and identification of numerous biosynthetic gene clusters. | 2016 | 27738023 |
| [effects of calcification on respiratory quotient of cultured oyster crassostrea gigas and its fouling animals]. | respiratory quotient (rq) is one of the basic indices in physiology and energy metabolism of animals. when rq is calculated, the amount of released co2 is typically used directly. but for calcifying marine organisms, calcification which can affect dissolved inorganic carbon (dic) content in the water may cause methodological error to some extent, if it is ignored. in this paper, rq and o/n of cultured oyster crassostrea gigas and 3 marine fouling animal species (mytilus edulis, ciona intestinali ... | 2014 | 25223039 |