| nitric oxide's pulsatile release in lobster heart and its regulation by opiate signaling: pesticide interference. | data is emerging in the human and invertebrate literature demonstrating that mu opiate receptors and morphine are present in cardiovascular tissues in diverse animals, including human tissues, where they may be exerting a cardioregulatory role via stimulation of constitutive nitric oxide (no) production. | 2006 | 17136001 |
| cs2s04 gradients containing both hg2+ and ag+ effect the complete separation of satellite deoxyribonucleic acids having identical densities in neutral cscl gradients. | a combination of both ag(+) and hg(2+) in cs(2)so(4) effects the complete separation of two dnas having identical densities in cscl. satellite dnas of hermit crab, pagurus pollicaris, and lobster, homarus americanus, have been isolated by this means. | 2015 | 4522292 |
| sequential developmental acquisition of neuromodulatory inputs to a central pattern-generating network. | the activity of the adult stomatogastric ganglion (stg) depends on a large number of aminergic and peptidergic modulatory inputs. our aim is to understand the role of these modulatory inputs in the development of the central pattern-generating networks of the stg. therefore, we analyze the developmental and adult expressions of three neuropeptides in the stomatogastric nervous system of the lobsters homarus americanus and homarus gammarus by using wholemount immunocytochemistry and confocal micr ... | 1999 | 10340510 |
| comparative analysis of barnacle tropomyosin: divergence from decapod tropomyosins and role as a potential allergen. | tropomyosin, a myofibrillar protein of 35-38 kda, represents a major and cross-reactive allergen in decapod crustaceans. this study was initiated to clarify whether decapod-allergic patients also recognize tropomyosins of barnacles, crustaceans phylogenetically remote from decapods, which are locally consumed as a delicacy. on sds-page, a 37 kda protein was observed in all the heated extracts prepared from two species of decapods (american lobster homarus americanus and black tiger prawn penaeus ... | 2007 | 17321773 |
| larval development and metamorphosis of the american lobster homarus americanus (crustacea, decapoda): effect of eyestalk ablation and juvenile hormone injection. | removal of eyestalks of homarus americanus on different days and molting stages during larval development revealed that eyestalk tissue is involved in the larval and postlarval molting rhythm and in preparation for metamorphosis as early as the end of stage ii. eyestalk removal in stages ii and iii reduced the duration of larval and postlarval stages. eyestalk removal up to the end of stage ii delayed the completion of metamorphosis by one or two molts and caused additional development stages (d ... | 2012 | 3384311 |
| binding of oxygen and carbon monoxide to arthropod hemocyanin: an allosteric analysis. | the binding of oxygen and carbon monoxide to hemocyanin from the mangrove crab scylla serrata and the lobster homarus americanus has been studied by thin-layer optical absorption and front face fluorescence techniques. three types of experiments were performed on subunit and oligomeric preparations of each hemocyanin: oxygen binding, carbon monoxide binding, and oxygen-carbon monoxide competition studies. the results obtained from the subunit preparations of dissociated oligomers from both hemoc ... | 2014 | 3994961 |
| three-dimensional reconstruction of the musculature of various life cycle stages of the cycliophoran symbion americanus. | cycliophora is a very recently described phylum of acoelomate metazoans with a complex life cycle and a phylogenetic position that has been under debate ever since its discovery in 1995. symbion americanus, which lives attached to the mouthparts of the american lobster, homarus americanus, represents the second species described for the phylum. aiming to increase the morphological knowledge about this cryptic clade, the present study describes the muscle arrangement of the feeding stage, the att ... | 2009 | 18937332 |
| nutritional quality of the edible tissues of european lobster homarus gammarus and american lobster homarus americanus. | the clawed lobsters homarus gammarus and homarus americanus are high-priced and appreciated food items in southern europe. from a nutritional point of view there is still limited information on the chemical composition of edible tissues (muscle, hepatopancreas, and gonads) of both species. therefore, the aims of the present work were to study the proximate chemical composition, energy, fatty acid and amino acid profiles, and cholesterol content in each edible tissue of both species and to evalua ... | 2009 | 19334784 |
| identification and cardiotropic actions of sulfakinin peptides in the american lobster homarus americanus. | in arthropods, a group of peptides possessing a -y((so3h))ghm/lrfamide carboxy-terminal motif have been collectively termed the sulfakinins. sulfakinin isoforms have been identified from numerous insect species. in contrast, members of this peptide family have thus far been isolated from just two crustaceans, the penaeid shrimp penaeus monodon and litopenaeus vannamei. here, we report the identification of a cdna encoding prepro-sulfakinin from the american lobster homarus americanus. two sulfak ... | 2007 | 17575033 |
| molecular and mass spectral identification of the broadly conserved decapod crustacean neuropeptide pqiryhqcyfnpiscf: the first piscf-allatostatin (manduca sexta- or c-type allatostatin) from a non-insect. | the piscf-allatostatins (manduca sexta- or c-type allatostatins) are a family of pentadecapeptides characterized by a pyroglutamine blocked n-terminus, an unamidated-piscf c-terminus, and a disulfide bridge between two internal cys residues. several isoforms of piscf-ast are known, all from holometabolous insects. using a combination of transcriptomics and mass spectrometry, we have identified the first piscf-type peptides from a non-insect species. in silico analysis of crustacean ests identifi ... | 2010 | 19467234 |
| identification of a novel sodium-dependent fructose transport activity in the hepatopancreas of the atlantic lobster homarus americanus. | [(3)h]fructose and [(3)h]glucose transport were determined in brush-border membrane vesicles (bbmv), basolateral membrane vesicles (blmv) and isolated cells (e, r, f, b) of h. americanus (atlantic lobster) hepatopancreas. glucose transport in bbmv was equilibrative in the absence of sodium and concentrative in the presence of sodium. sodium-dependent glucose transport by bbmv was not inhibited by a tenfold molar excess of fructose. glucose transport by blmv was equilibrative and sodium independe ... | 2009 | 19483009 |
| tubulin evolution in insects: gene duplication and subfunctionalization provide specialized isoforms in a functionally constrained gene family. | the completion of 19 insect genome sequencing projects spanning six insect orders provides the opportunity to investigate the evolution of important gene families, here tubulins. tubulins are a family of eukaryotic structural genes that form microtubules, fundamental components of the cytoskeleton that mediate cell division, shape, motility, and intracellular trafficking. previous in vivo studies in drosophila find a stringent relationship between tubulin structure and function; small, biochemic ... | 2010 | 20423510 |
| mass spectrometric characterization and physiological actions of novel crustacean c-type allatostatins. | the crustacean stomatogastric ganglion (stg) is modulated by numerous neuropeptides that are released locally in the neuropil or that reach the stg as neurohormones. using 1,5-diaminonaphthalene (dan) as a reductive screening matrix for matrix-assisted laser desorption/ionization (maldi) mass spectrometric profiling of disulfide bond-containing c-type allatostatin peptides followed by electrospray ionization quadrupole time-of-flight (esi-q-tof) tandem mass spectrometric (ms/ms) analysis, we ide ... | 2009 | 19505516 |
| anti-lipopolysaccharide factors in the american lobster homarus americanus: molecular characterization and transcriptional response to vibrio fluvialis challenge. | two partial mrna sequences predicted to encode anti-lipopolysaccharide factors (alfs) were identified among expressed sequence tags generated from the american lobster homarus americanus and complete cdna sequences were obtained from library clones. comparison of the translated amino acid sequences to those publicly available confirmed similarity to arthropod anti-lipopolysaccharide factors. both protein sequences, designated alfha-1 and alfha-2, contained an n-terminal signal peptide and two ha ... | 2008 | 19956341 |
| identification of putative crustacean neuropeptides using in silico analyses of publicly accessible expressed sequence tags. | the development of expressed sequence tags (ests) for crustacean cdna libraries and their deposition in publicly accessible databases has generated a rich resource for peptide discovery in this commercially and ecologically important arthropod subphylum. here, we have conducted in silico searches of these databases for unannotated ests encoding putative neuropeptide precursors using the blast program tblastn, and have predicted the mature forms of the peptides encoded by them. the primary strate ... | 2008 | 18321503 |
| bioinformatic analyses of the publicly accessible crustacean expressed sequence tags (ests) reveal numerous novel neuropeptide-encoding precursor proteins, including ones from members of several little studied taxa. | ests have been generated for many crustacean species, providing an invaluable resource for peptide discovery in members of this arthropod subphylum. here, these data were mined for novel peptide-encoding transcripts, with the mature peptides encoded by them predicted using a combination of online peptide prediction programs and homology to known arthropod sequences. in total, 70 mature full-length/partial peptides representing members of 16 families/subfamilies were predicted, the vast majority ... | 2010 | 20064519 |
| dual control of cytosolic metals by lysosomal transporters in lobster hepatopancreas. | this study describes the membrane transport mechanisms used by lobster (homarus americanus) hepatopancreatic epithelial lysosomes to accumulate and sequester heavy metals from the cytosol, and thereby aid in the regulation of these ions entering the animal from dietary constituents. the present investigation extends previous work describing lysosomal metal uptake by cation exchange with protons and suggests that a second, parallel, lysosomal transport process involving metal-thiol conjugates may ... | 2010 | 20154192 |
| nuclear dna content variation associated with muscle fiber hypertrophic growth in decapod crustaceans. | we tested the hypothesis that hypertrophic muscle growth in decapod crustaceans is associated with increases in both the number of nuclei per fiber and nuclear dna content. the dna-localizing fluorochrome dapi (4',6-diamidino-2-phenylindole) and chicken erythrocyte standards were used with static microspectrophotometry and image analysis to estimate nuclear dna content in hemocytes and muscle fibers from eight decapod crustacean species: farfantepenaeus aztecus, palaemonetes pugio, panulirus arg ... | 2010 | 20237594 |
| use of herring bait to farm lobsters in the gulf of maine. | ecologists, fisheries scientists, and coastal managers have all called for an ecosystem approach to fisheries management, yet many species such as the american lobster (homarus americanus) are still largely managed individually. one hypothesis that has yet to be tested suggests that human augmentation of lobster diets via the use of atlantic herring (clupea harengus) as bait may contribute to recent increases in lobster landings. currently 70% of atlantic herring landings in the gulf of maine ar ... | 2010 | 20419167 |
| factors affecting post-capture survivability of lobster homarus americanus. | technological advances in gear and fishing practices have driven the global expansion of the american lobster live seafood market. these changes have had a positive effect on the lobster industry by increasing capture efficiency. however, it is unknown what effect these improved methods will have on the post-capture fitness and survival of lobsters. this project utilized a repeated measures design to compare the physiological changes that occur in lobsters over time as the result of differences ... | 2010 | 20662372 |
| identification and expression of mrnas encoding bursicon in the plesiomorphic central nervous system of homarus gammarus. | ecdysis in arthropods is a complex process, regulated by many neurohormones, which must be released in a precisely coordinated manner. in insects, the ultimate hormone involved in this process is the cuticle tanning hormone, bursicon. recently, this hormone has been identified in crustaceans. to further define the distribution of bursicon in crustacean nervous systems, and to compare hormone structures within the sub-phylum, cdnas encoding both bursicon subunits were cloned and sequenced from th ... | 2010 | 20691691 |
| analysis of expressed sequence tags (ests) and gene expression changes under different growth conditions for the ciliate anophryoides haemophila, the causative agent of bumper car disease in the american lobster (homarus americanus). | the scuticociliate anophryoides haemophila, causes bumper car disease in american lobster (homarus americanus) in commercial holding facilities in atlantic canada. while the parasite has been recognized since the 1970s and much has been learned about its biology, minimal molecular characterization exists. with genome consortiums turning to model organisms like the ciliates tetrahymena and paramecium, the amount of relevant sequence data available has made sequence surveys more attractive for gen ... | 2011 | 21527260 |
| gene discovery in carcinus maenas and homarus americanus via expressed sequence tags. | expressed sequence tags (ests) were produced for normalized cdna libraries prepared from several tissues of 2 marine crustaceans, the green shore crab carcinus maenas and the american lobster homarus americanus. tissues represented in the carcinus library were anterior and posterior gills, hypodermis, heart, hepatopancreas, antennal gland, brain, testis, and skeletal muscle, obtained from animals acclimated to 35 and 10ôç¦ salinity. tissues represented in the homarus library were gill, epipodite ... | 2006 | 21672795 |
| bioaccumulation and metabolic effects of the endocrine disruptor methoprene in the lobster, homarus americanus. | methoprene is a pesticide that acts as a juvenile hormone agonist. although developed initially against insects, it has since been shown to have toxic effects on larval and adult crustaceans. methoprene was one of several pesticides applied to the western long island sound (wlis) watershed area during the summer of 1999; the other pesticides were malathion, resmethrin, and sumethrin. these pesticides were applied as part of a county-by-county effort to control the mosquito vector of west nile vi ... | 2005 | 21676752 |
| transepithelial d-glucose and d-fructose transport across the american lobster, homarus americanus, intestine. | transepithelial transport of dietary d-glucose and d-fructose was examined in the lobster homarus americanus intestine using d-[(3)h]glucose and d-[(3)h]fructose. lobster intestines were mounted in a perfusion chamber to determine transepithelial mucosal to serosal (ms) and serosal to mucosal (sm) transport mechanisms of glucose and fructose. both ms glucose and fructose transport, as functions of luminal sugar concentration, increased in a hyperbolic manner, suggesting the presence of mucosal t ... | 2011 | 21697425 |
| aerococcus viridans expression of cpn60 is associated with virulence during infection of the american lobster, homarus americanus milne edwards. | the gram-positive bacterium aerococcus viridans var. homari is a well-documented causative agent of the lethal systemic disease gaffkemia in both the american lobster, homarus americanus, and the european lobster, homarus gammarus. previous phenotypic characterization has been unsuccessful at differentiating avirulent from virulent strains without performing lethal animal infection trials. recent genetic characterization of a. viridans strains through 16s rrna sequencing and random amplification ... | 2011 | 21988355 |
| ulcerative enteritis in homarus americanus: case report and molecular characterization of intestinal aerobic bacteria of apparently healthy lobsters in live storage. | an intermoult male american lobster, homarus americanus, with severe intestinal lesions was encountered while collecting samples of aerobic intestinal bacteria from lobsters held in an artificial sea-water recirculation aquarium system. grossly, the intestine was firm, thickened, and white. histologic examination revealed a severe, diffuse, ulcerative enteritis which spared the chitin-lined colon, somewhat similar to hemocytic enteritis of shrimp. the bacterial isolates from this lobster were co ... | 2008 | 18640120 |
| spectrophotometric and fluorescence studies of the interaction of adenine nucleotides with arginine kinase of homarus americanus. | | 1989 | 210171 |
| amino acid sequence of crustacean hyperglycemic hormone (chh) from the crayfish, orconectes limosus: emergence of a novel neuropeptide family. | the primary structure of the major form of chh from sinus glands of the crayfish, orconectes limosus, was determined by manual edman microsequencing. it is a 72-residue peptide with a calculated mr of 8400 da. in the number of residues, it is identical to the chh of carcinus maenas and very similar to mih (moult inhibiting hormone) of homarus americanus. all three peptides have pglu as n-terminus in common, and val-nh2 is the c-terminal residue in orconectes and carcinus chh. six cys residues oc ... | 2007 | 1800954 |
| mechanism of lactic acid oxidation catalyzed by lactate dehydrogenase from the tail muscle of homarus americanus. | | 1981 | 217308 |
| fmrfamidelike peptides of homarus americanus: distribution, immunocytochemical mapping, and ultrastructural localization in terminal varicosities. | the distribution of fmrfamidelike peptides was studied in the nervous system of the lobster homarus americanus by using immunocytochemical and radioimmunological techniques. by radioimmunoassay fmrfamidelike immunoreactivity (fli) was found in low levels (ca. 1 pmol/mg protein) throughout the ventral nerve cord and in much higher amounts (60-100 pmol/mg protein) in the neurosecretory pericardial organs. immunocytochemical studies showed fli in approximately 300-350 cell bodies, and in distinct n ... | 2004 | 3323267 |
| cloning of sarco-endoplasmic reticulum ca2+ -atpase (serca) from caribbean spiny lobster panulirus argus. | we have previously reported on calcium transport mechanisms in american lobster, homarus americanus, using (45)ca(2+) coupled with vesicle preparations of hepatopancreatic endoplasmic reticulum. the active transport of calcium across membranes bordering calcium-sequestering stores such as sarcoplasmic or endoplasmic reticulum is catalyzed by membrane-spanning proteins, the sarco-endoplasmic ca(2+)-atpases (sercas). in the study described here we used advanced bioinformatics and molecular techniq ... | 2009 | 18825387 |
| american lobsters (homarus americanus) not surviving during air transport: evaluation of microbial spoilage. | eighteen american lobsters (homarus americanus), dead during air transport, were analysed in order to evaluate the microbial population of meat, gills and gut: no specific studies have ever been conducted so far on the microbiological quality of american lobsters' meats in terms of spoilage microbiota. the meat samples showed very limited total viable counts, in almost all the cases below the level of 6 log cfu/g, while higher loads were found, as expected, in gut and gills, the most probable so ... | 2016 | 27800442 |
| thermal acclimation and stress in the american lobster, homarus americanus: equivalent temperature shifts elicit unique gene expression patterns for molecular chaperones and polyubiquitin. | using homologous molecular probes, we examined the influence of equivalent temperature shifts on the in vivo expression of genes coding for a constitutive heat shock protein (hsc70), heat shock proteins (hsps) (hsp70 and hsp90), and polyubiquitin, after acclimation in the american lobster, homarus americanus. we acclimated sibling, intermolt, juvenile male lobsters to thermal regimes experienced during overwintering conditions (0.4 +/- 0.3 degrees c), and to ambient pacific ocean temperatures (1 ... | 2002 | 11892992 |
| similarities between decapod and insect neuropeptidomes. | background. neuropeptides are important regulators of physiological processes and behavior. although they tend to be generally well conserved, recent results using trancriptome sequencing on decapod crustaceans give the impression of significant differences between species, raising the question whether such differences are real or artefacts. methods. the blast+ program was used to find short reads coding neuropeptides and neurohormons in publicly available short read archives. such reads were th ... | 2016 | 27257538 |
| identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the american lobster, homarus americanus, cardiac neuromuscular system. | in insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. here, we show that a member of the insect calcitonin-like diuretic hormone (cldh) family is present in the american lobster, homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. specifically, during an ongoing est project, a transcript encoding a putative h. americanus cldh precu ... | 0 | 20008368 |
| electrical coupling and innexin expression in the stomatogastric ganglion of the crab cancer borealis. | gap junctions are intercellular channels that allow for the movement of small molecules and ions between the cytoplasm of adjacent cells and form electrical synapses between neurons. in invertebrates, the gap junction proteins are coded for by the innexin family of genes. the stomatogastric ganglion (stg) in the crab cancer borealis contains a small number of identified and electrically coupled neurons. we identified innexin 1 (inx1), innexin 2 (inx2), innexin 3 (inx3), innexin 4 (inx4), innexin ... | 2014 | 25210156 |
| aerococcus viridans var. homari: the presence of capsule and the relationship to virulence in american lobster (homarus americanus). | the relationship between virulence and encapsulation of aerococcus viridans var. homari was evaluated by growing virulent (rabin's) and avirulent (atcc 10400) strains under varying culture conditions, and during challenge trials. changes in capsule thickness were monitored using a modified lysine-ruthenium red (lrr) fixation method and transmission electron microscopy. the virulent rabin's strain possessed a prominent capsule of 0.252 μm±0.061 μm that was diminished by in vitro growth conditions ... | 2016 | 26598140 |
| comparative tissue expression of american lobster (homarus americanus) immune genes during bacterial and scuticociliate challenge. | the american lobster (homarus americanus) fishery is the most economically significant fishery in canada; although comparatively little is known about the lobsters' response to pathogenic challenge. this is the first study to investigate the expression of immune genes in tissues outside of the lobster hepatopancreas in response to challenges by the gram-positive bacteria, aerococcus viridans var. homari or the scuticociliate parasite, anophryoides haemophila. the hepatopancreas has been regarded ... | 2015 | 26551049 |
| a transcriptomic analysis of american lobster (homarus americanus) immune response during infection with the bumper car parasite anophryoides haemophila. | anophryoides haemophila is an important protistan parasite of american lobster, homarus americanus, as it has been found to infect lobsters in the wild as well as causing major losses of lobsters maintained in commercial holding facilities. expression of over 14,500 h. americanus hepatopancreatic genes were monitored during an a. haemophila infection challenge in order to elucidate molecular mechanisms involved in the lobster immune response. one hundred and forty-five genes were found to be dif ... | 2013 | 23470455 |
| differential expression of american lobster (homarus americanus) immune related genes during infection of aerococcus viridans var. homari, the causative agent of gaffkemia. | this is the first transcriptomic study focusing on immunity in the commercially valuable american lobster (homarus americanus). we have conducted an in vivo infection trial using the gram-positive bacterium aerococcus viridans var. homari to determine how h. americanus responds to this naturally occurring lethal-pathogen. a novel h. americanus microarray was used to measure the transcriptomic changes occurring in over 14,000 genes in the lobster hepatopancreas. hundreds of new immune genes and i ... | 2013 | 23229077 |
| limited prevalence of gaffkaemia (aerococcus viridans var. homari) isolated from wild-caught european lobsters homarus gammarus in england and wales. | gaffkaemia, caused by aerococcus viridans var. homari, causes fatal infections in homarus spp. (clawed lobsters). despite its high economic significance to the lobster fisheries in the usa and northern europe, data on its prevalence in captured and wild populations, particularly in europe, is scarce. following an outbreak of gaffkaemia in a european lobster holding facility in south wales (uk), a base-line survey was conducted for gaffkaemia in wild populations of european lobster homarus gammar ... | 2012 | 23186703 |
| safety of florfenicol in the adult lobster (homarus americanus). | aerococcus viridans, the causative agent of the disease gaffkemia, was a major cause of mortality in lobsters (homarus americanus) held in tidal impoundments during the 1970s and 1980s. despite reports of an increase in the mortality of lobsters during impoundment, and the widespread prophylactic use of oxytetracycline against a. viridans, this bacterium has not been detected in active disease surveillance of the maine postcapture lobster population. however, photobacterium indicum may be an eme ... | 2011 | 22946384 |
| effects of formalin, chloramine-t, and low salinity dip on the behavior and hemolymph biochemistry of the american lobster. | the purpose of this research was to investigate the salinity and formalin sensitivity of a ciliate parasite (anophryoides haemophila) of the american lobster (homarus americanus), and to examine the target-animal (lobster) safety of chemical-bath treatments involving low salinity, formalin, or chloramine-t that could be used to control this parasite in lobster pounds. "bumper car" disease, caused by an. haemophila, is an important concern to lobster pound operators in eastern north america, beca ... | 1996 | 9111691 |
| functional characterization of a novel disaccharide transporter in lobster hepatopancreas. | in animals, the accepted model of carbohydrate digestion and absorption involves reduction of disaccharides into the monosaccharides glucose, fructose, and galactose followed by their individual transmembrane transport into cells. in 2011, a gene for a distinct disaccharide sucrose transporter (scrt) was found in drosophila melanogaster and characterized in a yeast expression system. the purpose of the present investigation was to functionally identify and characterize a putative disaccharide tr ... | 2017 | 28180997 |
| identification of sywkqcafnavscfamide: a broadly conserved crustacean c-type allatostatin-like peptide with both neuromodulatory and cardioactive properties. | the allatostatins comprise three structurally distinct peptide families that regulate juvenile hormone production by the insect corpora allata. a-type family members contain the c-terminal motif -yxfglamide and have been found in species from numerous arthropod taxa. members of the b-type family exhibit a -wx(6)wamide c-terminus and, like the a-type peptides, appear to be broadly conserved within the arthropoda. by contrast, members of the c-type family, typified by the unblocked c-terminus -pis ... | 2009 | 19423507 |
| primary structures of decapod crustacean metallothioneins with special emphasis on freshwater and semi-terrestrial species. | cadmium injections induced only a single form of metallothionein (mt) in the midgut gland of potamon potamios, whereas the same treatment induced two isoforms in astacus astacus. the only difference between the two latter isoforms was that one had an extra n-terminal methionine residue. mt from p. potamios showed structural differences from other decapod crustacean mts. it contained a gly-thr motif at positions 8 and 8a, which had previously been found only in certain vertebrate and molluscan mt ... | 1996 | 8921011 |
| quantitative determination and distribution of the myotropic neuropeptide orcokinin in the nervous system of astacidean crustaceans. | for quantitative determinations of orcokinin, an indirect, noncompetitive sandwich elisa was developed. this elisa is highly specific for orcokinin and the detection limit is 1 fmol. in three astacidean species (orconectes limosus, homarus americanus, and astacus astacus) orcokinin immunoreactivity (ok-ir) was measurable in all parts of the nervous system. upon normalization to the protein content of the tissue (pmol/mg protein), concentrations were shown to be in the same range in all three spe ... | 1994 | 7937311 |
| characterization of a membrane-bound angiotensin-converting enzyme isoform in crayfish testis and evidence for its release into the seminal fluid. | in the present study, an isoform of angiotensin-converting enzyme was characterized from the testis of a decapod crustacean, the crayfish astacus leptodactylus. angiotensin-converting enzyme cdna, obtained by 3'- to 5' race of testis rnas, codes for a predicted one-domain protein similar to the mammalian germinal isoform of angiotensin-converting enzyme. all amino acid residues involved in enzyme activity are highly conserved, and a potential c-terminus transmembrane anchor may be predicted from ... | 2009 | 19656189 |
| distribution of centrifugal neurons targeting the soma clusters of the olfactory midbrain among decapod crustaceans. | to determine the distribution of two systems of centrifugal neurons innervating the soma clusters of the olfactory midbrain across decapod crustaceans, brains of the following nine species comprising most infraorders were immunostained with antibodies against dopamine and the neuropeptides substance p and fmrfamide: macrobrachium rosenbergii, homarus americanus, cherax destructor, orconectes limosus, procambarus clarkii, astacus leptodactylus, carcinus maenas, eriocheir sinensis and pagurus bern ... | 1997 | 9106436 |
| cold-adapted digestive aspartic protease of the clawed lobsters homarus americanus and homarus gammarus: biochemical characterization. | aspartic proteinases in the gastric fluid of clawed lobsters homarus americanus and homarus gammarus were isolated to homogeneity by single-step pepstatin-a affinity chromatography; such enzymes have been previously identified as cathepsin d-like enzymes based on their deduced amino acid sequence. here, we describe their biochemical characteristics; the properties of the lobster enzymes were compared with those of its homolog, bovine cathepsin d, and found to be unique in a number of ways. the l ... | 2013 | 22648335 |
| interpopulation and context-related differences in responses of a marine gastropod to predation risk. | we conducted laboratory experiments to investigate interpopulation differences in the behavioural responses of the whelk buccinum undatum to the predatory lobster homarus americanus and the asteroid leptasterias polaris, both in the absence and presence of feeding opportunities. whelks from three populations in the eastern north atlantic (1) responded to lobsters by displaying avoidance behaviours (burrowing in the sediments or retreating inside their shell), (2) responded to asteroids by displa ... | 1999 | 10202105 |
| the lethality of salmosan (azamethiphos) to american lobster (homarus americanus) larvae, postlarvae, and adults. | the pesticide formulation salmosan (47.5% w/w azamethiphos) is currently registered for use, in canada, to treat salmonids for infestations of the copepod parasites, lepeophtheirus salmonis and caligus elongatus (sea lice). determination was made of the acute lethality of this product to the three larval stages, the first postlarval stage, and the adult of the american lobster (homarus americanus), a species of significant economic importance in eastern canada. the 48-h lc50 (as azamethiphos) is ... | 1999 | 10375419 |
| lethality of pyrethrins to larvae and postlarvae of the american lobster (homarus americanus). | pesticide formulations containing pyrethrins are being used to treat salmonids for infestations of the copepod parasites lepeophtherius salmonis and caligus elongatus (sea lice). the acute lethality of one such formulation to four larval stages of the american lobster (homarus americanus), a species of significant economic importance in eastern canada, was determined. the formulation tested contained 0.06% pyrethrins and 0.6% piperonyl butoxide (a synergist). stage i larvae (48-h lc50 = 4.42 mic ... | 1997 | 9417857 |
| the o-diphenol oxidase activity of arthropod hemocyanin. | arthropod hemocyanin (isolated from the crab carcinus maenas and the lobster homarus americanus) is usually referred to as an oxygen transport-storage protein. the protein, however, also catalyses with low efficiency the oxidation of o-diphenol to quinone, similarly to tyrosinase (monophenol, o-diphenol:oxygen oxidoreductase). the enzymatic parameters of hemocyanin are affected by the aggregation state of the protein; namely v(max) exhibited by a dissociated subunit is one order of magnitude gre ... | 1996 | 8617365 |
| cu(ii) coordination in arthropod and mollusk green half-methemocyanins analyzed by electron spin-echo envelope modulation spectroscopy. | hemocyanin (hc) is a dinuclear copper protein that binds oxygen reversibly. the structure of the cu(ii) site in a derivative of hemocyanin known as green half-met (ghm) has been analyzed using the pulsed epr technique of electron spin-echo envelope modulation (eseem) spectroscopy. the derivative, prepared by treating the native protein with nitrite at low ph, contains a mixed-valent binuclear copper center. it was shown through chemical assays and the ligand exchange reaction products identified ... | 1995 | 7849010 |
| molecular cloning and sequence analysis of a cdna encoding a molt-inhibiting hormone-like neuropeptide from the white shrimp penaeus vannamei. | the x-organ of the eyestalk in crustaceans is a source of neurosecretory peptides. total rna was isolated from x-organs of the white shrimp penaeus vannamei and used to clone a cdna encoding a molt-inhibiting hormone-like (mih-like) neuropeptide by the 3' and 5' rapid amplification of cdna ends (race) method. sequence analysis of the 470-bp cdna reveals a 306-bp open reading frame and a 164-bp 3' untranslated region. the deduced polypeptide consists of a 72-amino acid mature peptide and a 30-ami ... | 1994 | 8055060 |
| primary structure of the major isomorph of the crustacean hyperglycemic hormone (chh-i) from the sinus gland of the mexican crayfish procambarus bouvieri (ortmann): interspecies comparison. | the amino acid sequence of this neuropeptide was elucidated by means of a combined approach of enzymatic digestions, manual and automatic edman degradations, and mass spectrometry. it is a 72 residue peptide (molecular mass 8388 da), with six cysteines forming three disulfide bridges connecting residues 7-43, 23-39, and 26-52, with blocked n- and c-termini, and lacking the amino acids histidine, methionine, and tryptophan. the chh-i of procambarus bouvieri is compared with the other known chhs f ... | 2011 | 8441709 |
| isolation of a neuropeptide from locust corpus cardiacum which influences ileal transport. | 1. schistocerca gregaria ion-transport peptide (scg-itp) was isolated from aqueous extracts of the corpus cardiacum by a four-step procedure, utilizing reverse-phase high-performance liquid chromatography for separation and stimulation of a cl(-)-dependent short-circuit current (isc) across locust ilea as the bioassay. 2. scg-itp has an unblocked n terminus and an apparent relative molecular mass of 7700. thirty-one residues (of an estimated 65) were identified by sequence analysis. 3. scg-itp i ... | 1992 | 1487715 |
| isolation and amino acid sequence of crustacean hyperglycemic hormone precursor-related peptides. | the crustacean hyperglycemic hormone (chh) is synthesized as part of a larger preprohormone in which the sequence of chh is n-terminally flanked by a peptide for which the name cprp (chh precursor-related peptide) is proposed. both chh and cprp are present in the sinus gland, the neurohemal organ of neurosecretory cells located in the eyestalk of decapod crustaceans. this paper describes the isolation and sequence analysis of cprps isolated from sinus glands of the crab carcinus maenas, the cray ... | 2011 | 1788131 |
| immunochemical and immunocytochemical studies of the crustacean vitellogenesis-inhibiting hormone (vih). | immunochemical investigations, using dot immunobinding assay (dia) and enzyme-linked immunosorbent assay (elisa), and immunocytochemical studies reveal the following new information about crustacean vitellogenesis-inhibiting hormone (vih): (1) the structure of vih is sufficiently different from that of the other sinus gland neuropeptides to allow a selective recognition of vih by polyclonal antibodies. (2) from immunochemical criteria, vih does not seem strictly species specific. the antisera ra ... | 1987 | 3666410 |
| the complete mitochondrial genome of the american lobster, homarus americanus (crustacea, decapoda). | although relatively a large number of the complete mitochondrial genome sequences have been determined from various decapod species (29 mtdna sequences reported so far), the information for the infraorder astacidea (including lobsters, crayfishes, and their relatives) is very limited and represented by only one complete sequence from the australian freshwater crayfish species cherax destructor. in this study, we determined the complete mitochondrial dna sequence of homarus americanus, the first ... | 2011 | 21740340 |
| adult neurogenesis in the crayfish brain: proliferation, migration, and possible origin of precursor cells. | the birth of new neurons and their incorporation into functional circuits in the adult brain is a characteristic of many vertebrate and invertebrate organisms, including decapod crustaceans. precursor cells maintaining life-long proliferation in the brains of crayfish (procambarus clarkii, cherax destructor) and clawed lobsters (homarus americanus) reside within a specialized niche on the ventral surface of the brain; their daughters migrate to two proliferation zones along a stream formed by pr ... | 2009 | 19294644 |
| putative neurohemal release zones in the stomatogastric nervous system of decapod crustaceans. | the stomatogastric nervous system (stns) of decapod crustaceans has long been used to study the modulation of small neural circuits. profiles in the sheath of the nerves and ganglia of the stns, which contain only dense-core vesicles, have been described in electron microscopical studies (friend [1976] cell tissue res. 175:369-380; kilman and marder [1997] soc neurosci abstr. 23:477; skiebe and ganeshina [2000] j comp neurol 420:373-397). these profiles resemble those found in neurohemal organs ... | 2002 | 12378588 |
| synaptic neuropil in nerves of the crustacean stomatogastric nervous system: an immunocytochemical and electron microscopical study. | patches of peptide-immunoreactive varicosities have been found in nerves of the stomatogastric nervous system (stns) of decapod crustaceans. in the present study, these patches were examined in detail in the stomatogastric nerve (stn) and in the superior oesophageal nerve (son) of the crayfish cherax destructor by using whole-mount immunocytochemical techniques combined with confocal microscopy and, in addition, electron microscopy. double-labeling experiments with antibodies generated against t ... | 2000 | 10754509 |
| tailflick escape behavior in larval and juvenile lobsters (homarus americanus) and crayfish (cherax destructor). | we examined the escape behavior of larvae and postlarvae of the american lobster (homarus americanus) and of adult immature (stage adi) crayfish (cherax destructor). responses to standardized water jet stimuli delivered through a pipette were observed and analyzed. lobster larvae did not respond to stimuli within 60 ms, indicating that they do not have functional giant fibers. the first movement by lobster larvae in response to water jet stimuli was a hyperextension of the abdomen. larval escape ... | 2000 | 10897445 |
| allatostatin-like immunoreactivity in the stomatogastric nervous system and the pericardial organs of the crab cancer pagurus, the lobster homarus americanus, and the crayfish cherax destructor and procambarus clarkii. | the distribution of allatostatin (ast)-like immunoreactivity was studied in the stomatogastric nervous system (stns) and the neurosecretory pericardial organs (po) of four decapod crustacean species by using wholemount immunocytochemical techniques and confocal microscopy. ast-like immunoreactivity was found within the stns of all four species; its distribution in each was unique. in all four species, ast-like immunoreactivity was present in the paired commissural ganglia (cog), in the esophagea ... | 1999 | 10075445 |
| comparative brain ontogeny of the crayfish and clawed lobster: implications of direct and larval development. | the freshwater crayfish cherax destructor and the lobster homarus americanus have many similarities including life style, body form, and neural organization. however, the ontogenic history is very different in the two species. the development of cherax is short and direct whereas the development of homarus comprises three pelagic larval stages and takes more than twice as long from extrusion to benthic stages at constant temperature. in order to determine the progression of maturation of the ner ... | 1993 | 8227524 |
| studies on proteins in post-ecdysial nymphal cuticle of locust, locusta migratoria, and cockroach, blaberus craniifer. | proteins were extracted from the cuticle of mid-instar nymphs of locusts, locusta migratoria, and cockroaches, blaberus craniifer. seven proteins were purified from the locust extract and five from the cockroach extract, and their amino acid sequences were determined. polyacrylamide gel electrophoresis indicates that the proteins are present only in the post-ecdysially deposited layer of the nymphal cuticles. one of the locust and one of the cockroach nymphal proteins contain a 68-residue motif, ... | 2000 | 10844249 |
| lesion bacterial communities in american lobsters with diet-induced shell disease. | in southern new england, usa, shell disease affects the profitability of the american lobster homarus americanus fishery. in laboratory trials using juvenile lobsters, exclusive feeding of herring clupea harengus induces shell disease typified initially by small melanized spots that progress into distinct lesions. amongst a cohabitated, but segregated, cohort of 11 juvenile lobsters fed exclusively herring, bacterial communities colonizing spots and lesions were investigated by denaturing gradie ... | 2012 | 22535872 |
| catalytic properties of lactate dehydrogenase in homarus americanus. | | 1997 | 20049 |
| effect of meal size and body size on specific dynamic action and gastric processing in decapod crustaceans. | meal size and animal size are important factors affecting the characteristics of the specific dynamic action (sda) response across a variety of taxa. the effects of these two variables on the sda of decapod crustaceans are based on just a couple of articles, and are not wholly consistent with the responses reported for other aquatic ectotherms. therefore, the effects of meal size and animal size on the characteristics of sda response were investigated in a variety of decapod crustaceans from dif ... | 2013 | 23916818 |
| rheb, an activator of target of rapamycin, in the blackback land crab, gecarcinus lateralis: cloning and effects of molting and unweighting on expression in skeletal muscle. | molt-induced claw muscle atrophy in decapod crustaceans facilitates exuviation and is coordinated by ecdysteroid hormones. there is a 4-fold reduction in mass accompanied by remodeling of the contractile apparatus, which is associated with an 11-fold increase in myofibrillar protein synthesis by the end of the premolt period. loss of a walking limb or claw causes a loss of mass in the associated thoracic musculature; this unweighting atrophy occurs in intermolt and is ecdysteroid independent. my ... | 2012 | 22279066 |
| subunit composition and n-terminal analysis of arthropod hemocyanins. | fourteen structural subunits of hemocyanins from two different infraorders of crustacea, brachyura (maia squinado, carcinus maenas) and astacidea (homarus americanus) were isolated and characterized. n-terminal amino acid sequences were determined and compared with known sequences of crustacean and cheliceratan hemocyanins. relationships between the investigated polypeptide chains were established. the results demonstrate that the degree of identity, calculated from the amino terminal sequences, ... | 1999 | 10327595 |
| a comparative immunocytochemical study of the hyperglycaemic, moult-inhibiting and vitellogenesis-inhibiting neurohormone family in three species of decapod crustacea. | eyestalks of the palinuran species jasus lalandii and panulirus homarus, and the brachyuran species carcinus maenas, were examined with antisera raised against purified crustacean hyperglycaemic hormone (chh) of the astacidean species homarus americanus and procambarus bouvieri, as well as the brachyuran species cancer pagurus. other antisera used in this investigation were raised against purified moult-inhibiting hormone (mih) of c. pagurus and vitellogenesis-inhibiting hormone (vih) of h. amer ... | 1999 | 9931363 |
| distribution of presumptive chemosensory afferents with fmrfamide- or substance p-like immunoreactivity in decapod crustaceans. | in five species of decapod crustaceans--cherax destructor (crayfish), carcinus maenas (crab), homarus americanus (clawed lobster), eriocheir sinensis (crab), macrobrachium rosenbergii (shrimp)--immunocytochemical stainings revealed the presence of sensory afferents with fmrfamide-like immunoreactivity in the central nervous system. these afferents were extremely thin, very numerous, and innervated all sensory neuropils except the optic and olfactory lobes. in their target neuropils they gave ris ... | 1997 | 9037486 |
| top-down and bottom-up forces interact at thermal range extremes on american lobster. | exploited marine populations are thought to be regulated by the effects of fishing, species interactions and climate. yet, it is unclear how these forces interact and vary across a species' range. we conducted a meta-analysis of american lobster (homarus americanus) abundance data throughout the entirety of the species' range, testing competing hypotheses about bottom-up (climate, temperature) vs. top-down (predation, fishing) regulation along a strong thermal gradient. our results suggest an in ... | 2015 | 25418350 |
| bacterial communities associated with lesions of two forms of shell disease in the american lobster (homarus americanus, milne edwards) from atlantic canada. | shell disease is a major threat to the american lobster (homarus americanus, milne edwards) fishery. here we describe the composition of microbial communities associated with lesions of 2 forms of shell disease in atlantic canada, (i) a trauma shell disease (tsd) characterized by massive lesions and (ii) an enzootic shell disease (ensd) characterized by irregularly shaped lesions with a distinct orange to yellow color. the microbiology of the lesions was described by polymerase chain reaction an ... | 2013 | 23750952 |
| culture-independent analysis of bacterial communities in hemolymph of american lobsters with epizootic shell disease. | epizootic shell disease (esd) of the american lobster homarus americanus h. milne edwards, 1837 is a disease of the carapace that presents grossly as large, melanized, irregularly shaped lesions, making the lobsters virtually unmarketable because of their grotesque appearance. we analyzed the bacterial communities present in the hemolymph of lobsters with and without esd using nested-pcr of the 16s rrna genes followed by denaturing gradient gel electrophoresis. all lobsters tested (n = 42) had b ... | 2013 | 23548364 |
| molecular immune response of the american lobster (homarus americanus) to the white spot syndrome virus. | the adult american lobster (homarus americanus) is susceptible to few naturally occurring pathogens, and no viral pathogen is known to exist. despite this, relatively little is known about the h. americanus immune system and nothing is known about its potential viral immune response. hundreds of rural communities in atlantic canada rely on the lobster fishery for their economic sustainability and could be devastated by large-scale pathogen-mediated mortality events. the white spot syndrome virus ... | 2013 | 24045127 |
| cloning of skeletal myosin heavy chain gene family from adult pleopod muscle and whole larvae of shrimps. | the physiological and biological properties of skeletal muscle in crustacea have not been well understood compared with those of vertebrates. the present study focused on myosin, the major protein in skeletal muscle, from shrimps. in our previous study, two full-length genes encoding myosin heavy chain (mhc), a large subunit of the myosin molecule, were cloned from abdominal fast skeletal muscle of kuruma marsupenaeus japonicus, black tiger penaeus monodon and pacific white penaeus vannamei shri ... | 2013 | 23526764 |
| distribution and regulation of esterases that hydrolyze methyl farnesoate in homarus americanus and other crustaceans. | ester hydrolysis of methyl farnesoate (mf) by crustacean tissue homogenates was measured using the substrate [3h]mf in a radiochemical partition assay. tissues were obtained from the lobster homarus americanus, penaeid shrimp sicyonia ingentis, thalanassid shrimp callianassa californiensis, sand crab emerita analoga, and spider crab pugettia producta. the greatest specific activities were recovered from the hepatopancreas (239 to 11,500 pmol mf/min-mg total protein). hepatopancreatic homogenates ... | 1997 | 9126466 |
| molecular, mass spectral, and physiological analyses of orcokinins and orcokinin precursor-related peptides in the lobster homarus americanus and the crayfish procambarus clarkii. | recently, cdnas encoding prepro-orcokinins were cloned from the crayfish procambarus clarkii; these cdnas encode multiple copies of four orcokinin isoforms as well as several other peptides. using the translated open reading frames of the p. clarkii transcripts as queries, five ests encoding american lobster homarus americanus orthologs were identified via blast analysis. from these clones, three cdnas, each encoding one of two distinct prepro-hormones, were characterized. predicted processing o ... | 2009 | 19007832 |
| neuropeptides and related nucleic acid sequences detected in peneid shrimps by immunohistochemistry and molecular hybridizations. | the neurosecretory cells in the eyestalks of penaeus indicus and p. vannamei were studied by immunocytochemistry using polyclonal antisera raised against purified homarus americanus neuropeptides. cross-reactions between two h. americanus anti-crustacean hyperglycemic hormone antisera and penaeus neurosecretory material were observed. the specific anti-vitellogenesis inhibiting hormone antiserum only showed an immunological reaction in the nervous tract and the sinus gland of penaeus, suggesting ... | 1994 | 8072696 |
| evidence that potential fish predators elicit the production of carapace vibrations by the american lobster. | american lobsters (homarus americanus) will on rare occasions produce sounds by vibrating their dorsal carapace. although this behavior can be elicited in the laboratory by handling lobsters, the stimulus that triggers the production of sounds in the lobster's natural habitat is not known. we investigated the influence of two fish that are known to prey on lobsters, cod (gadus morhua) and striped bass (morone saxatilis), on the production of sounds by american lobsters. in addition, we examined ... | 2011 | 21753058 |
| cuticles of european and american lobsters harbor diverse bacterial species and differ in disease susceptibility. | diseases of lobster shells have a significant impact on fishing industries but the risk of disease transmission between different lobster species has yet to be properly investigated. this study compared bacterial biofilm communities from american (homarus americanus) and european lobsters (h. gammarus), to assess both healthy cuticle and diseased cuticle during lesion formation. culture-independent molecular techniques revealed diversity in the bacterial communities of cuticle biofilms both with ... | 2014 | 24817518 |
| 65zn2+ transport by isolated gill epithelial cells of the american lobster, homarus americanus. | gills are the first site of impact by metal ions in contaminated waters. work on whole gill cells and metal uptake has not been reported before in crustaceans. in this study, gill filaments of the american lobster, homarus americanus, were dissociated in physiological saline and separated into several cell types on a 30, 40, 50, and 80% sucrose gradient. cells from each sucrose solution were separately resuspended in physiological saline and incubated in 65zn2+ in order to assess the nature of m ... | 2009 | 19198852 |
| stressed-out lobsters: crustacean hyperglycemic hormone and stress proteins. | organisms in natural habitats must frequently respond to changes in their environments through various physiological mechanisms. my laboratory has developed several methods for the quantification of stress in crustaceans. an elisa was developed for the crustacean hyperglycemic hormone (chh) from the american lobster (homarus americanus). it is sensitive to as little as 0.2 fmol of peptide. increases in hemolymph chh were observed under conditions of acute hypoxia, elevated temperature, and alter ... | 2005 | 21676744 |
| creation of a gilded trap by the high economic value of the maine lobster fishery. | unsustainable fishing simplifies food chains and, as with aquaculture, can result in reliance on a few economically valuable species. this lack of diversity may increase risks of ecological and economic disruptions. centuries of intense fishing have extirpated most apex predators in the gulf of maine (united states and canada), effectively creating an american lobster (homarus americanus) monoculture. over the past 20 years, the economic diversity of marine resources harvested in maine has decli ... | 2011 | 21797925 |
| excretory calcinosis: a new fatal disease of wild american lobsters homarus americanus. | a significant number of moribund and dead lobsters homarus americanus were reported to new york state authorities by lobster fishers in long island sound (lis) during the summer of 2002. morbid lobsters were characterised by an orange discolouration of the abdomen, lethargy, an excess of epibionts and poor post-capture survival. on necropsy, severe extensive multifocal or diffuse mineralised granulomatous inflammation of the gills and antennal glands was the most striking pathology. in the gills ... | 2004 | 15109145 |
| [identification of vibrio metschnikovii from homarus americanus and its changes in membrane fatty acid composition in response to low temperature]. | bacterial strain f5-1 isolated from the homarus americanus was characterized and its changes in membrane fatty acid composition in response to low temperature were also studied. | 2013 | 24028066 |
| impact of disease on the survival of three commercially fished species. | recent increases in emergent infectious diseases have raised concerns about the sustainability of some marine species. the complexity and expense of studying diseases in marine systems often dictate that conservation and management decisions are made without quantitative data on population-level impacts of disease. mark-recapture is a powerful, underutilized, tool for calculating impacts of disease on population size and structure, even in the absence of etiological information. we applied logis ... | 2017 | 28675580 |
| analysis of gene expression in homarus americanus larvae exposed to sublethal concentrations of endosulfan during metamorphosis. | agricultural pesticide runoff has been suspected as the cause of numerous fish kills in rivers throughout prince edward island but the impact on the surrounding marine environment is unknown. endosulfan, an organochlorine pesticide, is a potent neurotoxin and molt inhibitor used to combat the colorado potato beetle however it has the potential to affect non-target organisms including the american lobster (homarus americanus). metamorphosis is a critical stage of development and the effects of co ... | 2013 | 24041715 |