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molt-inhibiting hormone stimulates vitellogenesis at advanced ovarian developmental stages in the female blue crab, callinectes sapidus 1: an ovarian stage dependent involvement.to understand the hormonal coordination of the antagonism between molting and reproduction in crustaceans, the terminally anecdysial mature female callinectes sapidus was used as a model. the regulatory roles of crustacean hyperglycemic hormone (chh) and molt-inhibiting hormone (mih) in vitellogenesis were examined. a competitive specific ria was used to measure the levels of mih and chh in the hemolymphs of mature females at pre- and mid- vitellogenic stages, and their effects on vitellogenesis ...200919583852
spiny lobsters detect conspecific blood-borne alarm cues exclusively through olfactory sensilla.when attacked by predators, diverse animals actively or passively release molecules that evoke alarm and related anti-predatory behavior by nearby conspecifics. the actively released molecules are alarm pheromones, whereas the passively released molecules are alarm cues. for example, many insects have alarm-signaling systems that involve active release of alarm pheromones from specialized glands and detection of these signals using specific sensors. many crustaceans passively release alarm cues, ...200818689413
the crustacean gill (na+,k+)-atpase: allosteric modulation of high- and low-affinity atp-binding sites by sodium and potassium.the blue crab, callinectes danae, tolerates exposure to a wide salinity range employing mechanisms of compensatory ion uptake when in dilute media. although the gill (na+,k+)-atpase is vital to hyperosmoregulatory ability, the interactions occurring at the sites of atp binding on the molecule itself are unknown. here, we investigate the modulation by na+ and k+ of homotropic interactions between the atp-binding sites, and of phosphoenzyme formation of the (na+,k+)-atpase from the posterior gills ...200818796291
hepatopancreas alteration of the blue crab callinectes sapidus by the rhizocephalan barnacle loxothylacus texanus.a histological study of the hepatopancreas of the blue crab callinectes sapidus parasitized by the rhizocephalan barnacle loxothylacus texanus was conducted to explore if the degree of development of the parasite's rootlet system was correlated to its maturation process as seen by external characters of its reproductive body or externa. four types of crabs were examined: control, with virgin and mature externa, and scarred. a clear progression with an increase in number and size of the parasite' ...200818805422
studies of a receptor guanylyl cyclase cloned from y-organs of the blue crab (callinectes sapidus), and its possible functional link to ecdysteroidogenesis.crustacean y-organs synthesize ecdysteroid molting hormones. synthesis of ecdysteroids by y-organs is negatively regulated by a polypeptide neurohormone, molt-inhibiting hormone (mih). our laboratory has recently cloned from y-organs of the blue crab (callinectes sapidus) a cdna (csgc-yo1) encoding a putative receptor guanylyl cyclase (csgc-yo1). we hypothesize that csgc-yo1 is an mih receptor. in studies reported here, antipeptide antibodies (anti-csgc-yo1) were raised against a fragment of the ...200818093588
detection and discovery of crustacean parasites in blue crabs (callinectes sapidus) by using 18s rrna gene-targeted denaturing high-performance liquid chromatography.recently, we described a novel denaturing high-performance liquid chromatography (dhplc) approach useful for initial detection and identification of crustacean parasites. because this approach utilizes general primers targeted to conserved regions of the 18s rrna gene, a priori genetic sequence information on eukaryotic parasites is not required. this distinction provides a significant advantage over specifically targeted pcr assays that do not allow for the detection of unknown or unsuspected p ...200818502913
development of a denaturing high-performance liquid chromatography method for detection of protist parasites of metazoans.increasingly, diseases of marine organisms are recognized as significant biotic factors affecting ecosystem health. however, the responsible disease agents are often unknown and the discovery and description of novel parasites most often rely on morphological descriptions made by highly trained specialists. here, we describe a new approach for parasite discovery, utilizing denaturing high-performance liquid chromatography (dhplc) reverse-phase ion-pairing technology. systematic investigations of ...200818502933
identification of the extracellular copper-zinc superoxide dismutase (eccuznsod) gene of the mud crab scylla serrata and its expression following beta-glucan and peptidoglycan injections.an extracellular copper-zinc superoxide dismutase (eccuznsod, or ec-sod) gene was cloned from haemocytes of mud crab scylla serrata. the eccuznsod cdna consists of 939 bp with an open reading frame (orf) of 585 bp that encodes 195 amino acids (aa) with 31 residues of a signal peptide sequence. the predicted molecular mass of the mature protein (164aa) is 17.1 kda with an estimated pi of 6.89. amino acids responsible for binding cu (his84, 86, 101, and 163) and zn (his101, 109, and 121, and asp 1 ...200817949815
human and crab exposure to mercury in the caribbean coastal shoreline of colombia: impact from an abandoned chlor-alkali plant.human hair samples from male and female people aged 6-85 years, as well as muscle of crabs (callinectes sapidus and callinectes bocourti) were collected from different fishing places along the caribbean coastal shoreline of colombia and analyzed for total mercury (t-hg) in order to establish the impact of mercury-polluted sediments in cartagena bay on the ecosystem. hair t-hg in inhabitants varied between 0.1 and 21.8 microg/g, with average and median of 1.52 microg/g and 1.1 microg/g, respectiv ...200818155151
functional studies of crustacean hyperglycemic hormones (chhs) of the blue crab, callinectes sapidus - the expression and release of chh in eyestalk and pericardial organ in response to environmental stress.the rapid increase in the number of putative cdna sequences encoding crustacean hyperglycemic hormone (chh) family in various tissues [either from the eyestalk (es) or elsewhere] underscores a need to identify the corresponding neuropeptides in relevant tissues. moreover, the presence of provided structural chh implies the level of the complexity of physiological regulation in crustaceans. much less is known of the functions of non-es chh than of those of its counterpart present in ess. in the b ...200818190527
to paddle or not: context dependent courtship display by male blue crabs, callinectes sapidus.the nature of the courtship signalling used by a species is shaped by many factors, one of which is its habitat. male blue crabs, callinectes sapidus, have a courtship display in which they elevate their body by standing high on their legs, open their chelae and paddle their swimming legs. this courtship display is not reported in other swimming (portunid) crabs and is rarely expressed in laboratory experiments on male blue crabs. in this study, we characterised this display, which we call ;cour ...200818375848
simulated predator extinctions: predator identity affects survival and recruitment of oysters.the rate of species loss is increasing at a global scale, and human-induced extinctions are biased toward predator species. we examined the effects of predator extinctions on a foundation species, the eastern oyster (crassostrea virginica). we performed a factorial experiment manipulating the presence and abundance of three of the most common predatory crabs, the blue crab (callinectes sapidus), stone crab (menippe mercenaria), and mud crab (panopeus herbstii) in estuaries in the eastern united ...200818409432
comparison of fatty acid and proximate compositions of the body and claw of male and female blue crabs (callinectes sapidus) from different regions of the mediterranean coast.fatty acid and proximate compositions of the body and claw of male and female blue crabs from akyatan lagoon and hurma strait were investigated. male blue crab meat had a higher protein and fat content, and lower moisture and ash content, than that of the female from akyatan lagoon. moreover, there were variations of protein and fat amounts in both female crab meats between akyatan lagoon and hurma strait. the dominant saturated fatty acids were palmitic acid (16:0; range from approximately 12% ...200819382333
a trehalose 6-phosphate synthase gene of the hemocytes of the blue crab, callinectes sapidus: cloning, the expression, its enzyme activity and relationship to hemolymph trehalose levels.trehalose in ectoderms functions in energy metabolism and protection in extreme environmental conditions. we structurally characterized trehalose 6-phosphate synthase (tps) from hemocytes of the blue crab, callinectes sapidus. c. sapidus hemo tps (cashemotps), like insect tps, encodes both tps and trehalose phosphate phosphatase domains. trehalose seems to be a major sugar, as it shows higher levels than does glucose in hemocytes and hemolymph. increases in hemotps expression, tps enzyme activit ...200819077285
habitat complexity influences cascading effects of multiple predators.although multiple predator effects and trophic cascades have both been demonstrated in a wide variety of ecosystems, ecologists have yet to incorporate these studies into an experimental framework that also manipulates a common and likely important factor, spatial heterogeneity. we manipulated habitat complexity, the presence of two top predators (toadfish and blue crabs), and one intermediate predator (mud crabs) to determine whether habitat complexity influences the strength of multiple predat ...200819137947
clearance of vibrio campbellii injected into the hemolymph of callinectes sapidus, the atlantic blue crab: the effects of prior exposure to bacteria and environmental hypoxia.the atlantic blue crab, callinectes sapidus (rathbun), lives in a bacteria-rich environment that experiences daily fluctuations in water quality. in the present study, we tested the hypothesis that crustaceans with prior or ongoing exposure to bacteria in their hemolymph have an increased susceptibility to subsequent infections, and that acute exposure to low dissolved oxygen (hypoxia) and elevated carbon dioxide levels (hypercapnia) may further confound the ability of blue crabs to counter a su ...200818964085
decoding modulation of the neuromuscular transform.when modulators of neuromuscular function alter the motor neuron spike patterns that elicit muscle contractions, it is predicted that they will also retune correspondingly the connecting processes of the neuromuscular transform. here we confirm this prediction by analyzing data from the cardiac neuromuscular system of the blue crab. we apply a method that decodes the contraction response to the spike pattern in terms of three elementary building-block functions that completely characterize the n ...200719763188
[temporal and spatial distribution of the crab callinectes sapidus (decapoda: portunidae) in chetumal bay, quintana roo, mexico].in order to determine temporal and spatial distribution patterns of callinectes sapidus, samplings were carried out during the cold-front (january-february), dry (may-june) and rainy (august-september, 2002) climatic seasons, in 30 sampling stations of chetumal bay, grouped in sectors a (14 stations), b (eight stations) and c (eight stations). in each sampling station crabs were collected from two transects parallel to the coast, each with three traps, separated by 30 m. sediments were calcareou ...200718457132
mechanical properties of the rigid and hydrostatic skeletons of molting blue crabs, callinectes sapidus rathbun.molting in crustaceans involves significant changes in the structure and function of the exoskeleton as the old cuticle is shed and a new one is secreted. the flimsy new cuticle takes several days to harden and during this time crabs rely on a hydrostatic skeletal support system for support and movement. this change from a rigid to a hydrostatic skeletal support mechanism implies correlated changes in the function, and thus mechanical properties, of the cuticle. in particular, it must change fro ...200718055616
regulation of the crab heartbeat by fmrfamide-like peptides: multiple interacting effects on center and periphery.we are studying the functional "logic" of neuromodulatory actions in a simple central pattern generator (cpg)-effector system, the heart of the blue crab callinectes sapidus. the rhythmic contractions of this heart are neurogenic, driven by rhythmic motor patterns generated by the cardiac ganglion (cg). here we used anatomical and physiological methods to examine the sources and actions on the system of the fmrfamide-like peptides (flps) tnrnflrfamide (f(1)), sdrnflrfamide (f(2)), and gynrsflrfa ...200717804580
a comparison of blue crab and bivalve delta15n tissue enrichment in two north carolina estuaries.stable isotope analyses (delta(15)n) were used to examine invertebrate tissue enrichment in two north carolina estuaries with differing amounts of nutrient loading. bivalves collected from a nutrient sensitive estuary yielded a significant difference in mean nitrogen isotopic composition of tissue (10.4 per thousand+/-0.82; n=66) compared to bivalves collected from a less nutrient sensitive estuary (6.4 per thousand+/-0.63; n=45). similarly, blue crabs from nutrient sensitive sites had a nitroge ...200716714075
accumulation of organic and inorganic contaminants in shellfish collected in estuarine waters near pensacola, florida: contamination profiles and risks to human consumers.we conducted a screening level assessment of contaminants in blue crabs (callinectes sapidus) and oysters (crassostrea virginica) from bays and bayous in the pensacola, fl area. tissue samples were analyzed for 17 dioxins/furans, 12 dioxin-like pcb (dl-pcbs) congeners, mercury, and various metals. contaminant levels were compared to screening values (sv) calculated using u.s. epa recommendations for establishing consumption advisories. all sampling locations exceeded the sv (0.098pgg(-1)) for di ...200716872729
the mitochondrial manganese superoxide dismutase gene in chinese shrimp fenneropenaeus chinensis: cloning, distribution and expression.manganese superoxide dismutase (mnsod) plays an important role in crustacean immune defense reaction by eliminating oxidative stress. knowledge on mnsod at molecular level allows us to understand its regulatory mechanism in crustacean immune system. a novel mitochondrial manganese superoxide dismutase (mmnsod) was cloned from hepatopancreas of chinese shrimp fenneropenaeus chinensis by 3' and 5' rapid amplification of cdna ends (race) pcr. the full-length cdna consists of 1185bp with a 660bp ope ...200717097141
differences in enzyme activities between two species of hematodinium, parasitic dinoflagellates of crustaceans.parasitic dinoflagellates of the genus hematodinium infect several commercially important decapod crustaceans. different species of hematodinium have different levels of virulence in their respective hosts. enzyme activities were studied from two species of hematodinium, one isolated from the norway lobster (nephrops norvegicus) and the other from the american blue crab (callinectes sapidus). we report the identification of differences in secretion of acid phosphatase (ap) and leucine arylamidas ...200717156792
molecular cloning, characterization and expression of a masquerade-like serine proteinase homologue from black tiger shrimp penaeus monodon.a full-length cdna of a masquerade-like serine proteinase homologue (pmmassph) of penaeus monodon was cloned and characterized by rapid amplification cdna end (race) method. the complete cdna sequence of 1958bp contains an open reading frame (orf) of 1572bp, encoding a 523 amino acid protein including a 19 amino acid signal peptide. the calculated molecular mass of the mature protein (504 amino acids) is 51.58kda with an estimated pi of 4.86. pmmassph has most of the structural characteristics o ...200717174571
differential expression of eight transcripts and their roles in the cuticle of the blue crab, callinectes sapidus.eight cuticle protein transcripts from callinectes sapidus were sequenced and their expression determined across the molt cycle in both calcifying and arthrodial cuticle hypodermis using quantitative pcr, northern blots, and in situ hybridization. four transcripts, designated csamp, are found only in non-calcifying arthrodial membrane hypodermis. they all code for a rebers-riddiford-1 motif, known to bind chitin. csamp9.3 is most likely an exocuticle constituent since it is expressed only during ...200717188921
k+ and nh4(+) modulate gill (na+, k+)-atpase activity in the blue crab, callinectes ornatus: fine tuning of ammonia excretion.to better comprehend the mechanisms of ionic regulation, we investigate the modulation by na+, k+, nh4(+) and atp of the (na+, k+)-atpase in a microsomal fraction from callinectes ornatus gills. atp hydrolysis obeyed michaelis-menten kinetics with km=0.61+/-0.03 mmol l(-1) and maximal rate of v=116.3+/-5.4 u mg(-1). stimulation by na+ (v=110.6+/-6.1 u mg(-1); k0.5=6.3+/-0.2 mmol l(-1)), mg2+ (v=111.0+/-4.7 u mg(-1); k0.5=0.53+/-0.03 mmol l(-1)), nh4(+) (v=173.3+/-6.9 u mg(-1); k0.5=5.4+/-0.2 mmo ...200717276114
regulation of the crab heartbeat by crustacean cardioactive peptide (ccap): central and peripheral actions.in regulating neurophysiological systems, neuromodulators exert multiple actions at multiple sites in such a way as to control the activity in an integrated manner. we are studying how this happens in a simple central pattern generator (cpg)-effector system, the heart of the blue crab callinectes sapidus. the rhythmic contractions of this heart are neurogenic, driven by rhythmic motor patterns generated by the cardiac ganglion (cg). in this study, we used anatomical and physiological methods to ...200717303813
antilipopolysaccharide factor (alf) of mud crab scylla paramamosain: molecular cloning, genomic organization and the antimicrobial activity of its synthetic lps binding domain.antilipopolysaccharide factors (alfs) are small basic proteins that can bind and neutralize lipopolysaccharide (lps) and have broad spectrum antimicrobial activities. in this study, we describe the isolation of the full-length cdna encoding for alf peptide (alfsp) of mud crab, scylla paramamosain by sequencing a hemocyte cdna library and using the rapid amplification cdna end (race) method. a full-length alfsp cdna of 614 bp contains an open reading frame (orf) of 372 bp, encoding 123 amino acid ...200717368541
vitellogenin and its messenger rna during ovarian development in the female blue crab, callinectes sapidus: gene expression, synthesis, transport, and cleavage.blue crab vitellogenin (vtg) cdna encodes a precursor that, together with two other brachyuran vtgs, forms a distinctive cluster within a phylogenetic tree of crustacean vtgs. using quantitative rt-pcr, we found that vtg was primarily expressed in the hepatopancreas of a vitellogenic female, with minor expression in the ovary. vtg expression in the hepatopancreas correlated with ovarian growth, with a remarkable 8000-fold increase in expression from stage 3 to 4 of ovarian development. in contra ...200717409377
risk of handling as a route of exposure to infectious waterborne cryptosporidium parvum oocysts via atlantic blue crabs (callinectes sapidus).commercial atlantic blue crabs (callinectes sapidus) were exposed to 2.0x10(4) infectious waterborne oocysts of cryptosporidium parvum. the study demonstrated that blue crabs can transfer c. parvum oocysts to persons involved in handling or preparing crabs and that they may contaminate other surfaces or products during storage.200717449680
characterization of a shrimp serine protease homolog, a binding protein of yellow head virus.a serine protease homolog (sph) cdna namely sph516 was identified via a yeast two-hybrid screen between yellow head virus (yhv) proteins and hemocyte proteins of the black tiger shrimp penaeus monodon. initially, the c-terminal region of sph516 (sph516-c) was found to interact with a putative metal ion-binding domain (mib) encoded by open-reading of frame orf1b of the yhv genome. subsequently, the full-length of sph516 cdna was obtained using 5' rapid amplification of cdna ends (5' race) and it ...200717451807
salinity-stimulated changes in expression and activity of two carbonic anhydrase isoforms in the blue crab callinectes sapidus.two isoforms of the enzyme carbonic anhydrase (ca) in the blue crab gill, cascag and cascac, were identified, sequenced, and found to match the membrane-associated and cytoplasmic isoforms, respectively. the membrane-associated isoform is present in much higher levels of mrna expression in both anterior and posterior gills in crabs acclimated to high salinity (35 p.p.t.), but expression of the cytoplasmic isoform in the posterior gill undergoes a significantly greater degree of up-regulation aft ...200717575037
biological studies on the blue crab portunus pelagicus and its parasitic infection in kuwaiti waters.the study investigated the parasites of symbiotic fauna of the blue crab, portunus pelagicus and the environmental factors, which was lacking in kuwait. p. pelagicus feeding habits was studied by examination of the digestive tract. the foregut (stomach) contents of 250 crabs (110 male & 140 female) collected from fish-market, souq-sharq, edelyia capital governorate were investigated. a barnacle, balanus sp. and staked barnacle octolasmis sp. (crustacea: cirripedia) were found strongly firmly to ...200717580579
a sex-specific metabolite identified in a marine invertebrate utilizing phosphorus-31 nuclear magnetic resonance.hormone level differences are generally accepted as the primary cause for sexual dimorphism in animal and human development. levels of low molecular weight metabolites also differ between men and women in circulating amino acids, lipids and carbohydrates and within brain tissue. while investigating the metabolism of blue crab tissues using phosphorus-31 nuclear magnetic resonance, we discovered that only the male blue crab (callinectes sapidus) contained a phosphorus compound with a chemical shi ...200717712428
superfund dredging restoration results in widespread regional reduction in cadmium in blue crabs.a nickel-cadmium battery factory released about 53 tons of mostly cadmium and nickel hydroxide suspended solid waste between 1953 and 1979 into foundry cove, which is tidally connected to the hudson river estuary. a major superfund dredging cleanup in 1994-1995 removed most of the cadmium from the sediment from within foundry cove. here, we demonstrate that the cleanup reduced cadmium tissue concentrations (hepatopancreas and leg muscle) in an important fishery species, the blue crab callinectes ...200617256500
a reaction-diffusion analysis of energetics in large muscle fibers secondarily evolved for aerobic locomotor function.the muscles that power swimming in the blue crab, callinectes sapidus, grow hypertrophically, such that in juvenile crabs the cell diameters are <60 microm, whereas fibers of the adult crabs often exceed 600 microm. thus, as these animals grow, their muscle fibers greatly exceed the surface area to volume ratio and intracellular diffusion distance limits of most cells. previous studies have shown that arginine phosphate (ap) recovery in the anaerobic (light) fibers, which demonstrate a fiber siz ...200616943501
immune defense reduces respiratory fitness in callinectes sapidus, the atlantic blue crab.crustacean gills function in gas exchange, ion transport, and immune defense against microbial pathogens. hemocyte aggregates that form in response to microbial pathogens become trapped in the fine vasculature of the gill, leading to the suggestion by others that respiration and ion regulation might by impaired during the course of an immune response. in the present study, injection of the pathogenic bacterium vibrio campbellii into callinectes sapidus, the atlantic blue crab, caused a dramatic ...200616946241
expression profiles of na+,k+-atpase during acute and chronic hypo-osmotic stress in the blue crab callinectes sapidus.during acclimation to dilute seawater, the specific activity of na+,k+-atpase increases substantially in the posterior gills of the blue crab callinectes sapidus. to determine whether this increase occurs through regulation of pre-existing enzyme or synthesis of new enzyme, mrna and protein levels were measured over short (<24 h) and long (18 days) time courses. na+,k+-atpase expression, both mrna and protein, did not change during the initial 24-h exposure to dilute seawater (10 ppt salinity). ...200616946242
metal concentrations in blue crab (callinectes sapidus) and mullet (mugil cephalus) in iskenderun bay, northern east mediterranean, turkey. 200616977519
identification and developmental expression of mrnas encoding crustacean cardioactive peptide (ccap) in decapod crustaceans.full-length cdnas encoding crustacean cardioactive peptide (ccap) were isolated from several decapod (brachyuran and astacuran) crustaceans: the blue crab callinectes sapidus, green shore crab carcinus maenas, european lobster homarus gamarus and calico crayfish orconectes immunis. the cdnas encode open reading frames of 143 (brachyurans) and 139-140 (astacurans) amino acids. apart from the predicted signal peptides (30-32 amino acids), the conceptually translated precursor codes for a single co ...200616985202
expression of crustacean (callinectes sapidus) molt-inhibiting hormone in escherichia coli: characterization of the recombinant peptide and assessment of its effects on cellular signaling pathways in y-organs.a neuropeptide, molt-inhibiting hormone (mih), negatively regulates the synthesis of ecdysteroid molting hormones by crustacean y-organs. we report here the expression of blue crab (callinectes sapidus) mih in escherichia coli. bacteria were transformed with an expression plasmid containing a cdna insert encoding mih. after induction of protein synthesis, recombinant mih (recmih) was detected in the insoluble fraction of cell lysates. the insoluble recmih was refolded and purified by reversed-ph ...200616790313
clamming up: environmental forces diminish the perceptive ability of bivalve prey.the lethal and nonlethal impacts of predators in marine systems are often mediated via reciprocal detection of waterborne chemical signals between consumers and prey. local flow environments can enhance or impair the chemoreception ability of consumers, but the effect of hydrodynamics on detection of predation risk by prey has not been investigated. using clams as our model organism, we investigated two specific questions: (1) can clams decrease their mortality by responding to predators? (2) do ...200616869434
effect of salinity on osmoregulatory patch epithelia in gills of the blue crab callinectes sapidus.in euryhaline crabs, ion-transporting cells are clustered into osmoregulatory patches on the lamellae of the posterior gills. to examine changes in the branchial osmoregulatory patch in the blue crab callinectes sapidus in response to change in salinity and to correlate these changes with other osmoregulatory responses, crabs were acclimated to a range of salinities between 10 and 35 ppt. when crabs that had been acclimated to 35 ppt were subsequently transferred to 10 ppt, both the size of the ...200616641518
when r-selection may not predict introduced-species proliferation: predation of a nonnative oyster.predicting outcomes of species introductions may be enhanced by integrating life-history theory with results of contained experiments that compare ecological responses of exotic and analogue native species to dominant features of the recipient environment. an asian oyster under consideration for introduction to the chesapeake bay, usa, the rapidly growing suminoe oyster (crassostrea ariakensis), may not be as successful an invader as its r-selected life history suggests if the trade-off for rapi ...200616711058
the effects of hypoxia and ph on phenoloxidase activity in the atlantic blue crab, callinectes sapidus.in its natural coastal and estuarine environments, the blue crab, callinectes sapidus, often encounters hypoxia, accompanied by hypercapnia (increased co2) and an associated decrease in water ph. previous studies have shown that exposure to hypercapnic hypoxia (hh) impairs the crab's ability to remove culturable bacteria from its hemolymph. in the present study we demonstrate that the activity of phenoloxidase (po), an enzyme critical to antibacterial immune defense in crustaceans, is decreased ...200616616537
cloning and characterisation of mitochondrial manganese superoxide dismutase (mtmnsod) from the giant freshwater prawn macrobrachium rosenbergii.a cdna encoding a mitochondrial manganese superoxide dismutase (mtmnsod) was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by rapid amplification of cdna end (race) pcr method. analysis of nucleotide sequence revealed that the mtmnsod full-length cdna consists of 1202bp containing an open reading frame of 654bp, which encodes a protein c ...200616621606
molecular cloning of a cdna encoding a crustacean hyperglycemic hormone from eyestalk ganglia of the blue crab, callinectes sapidus.crustacean hyperglycemic hormone (chh), a polypeptide with multiple physiological effects, was first identified in the x-organ/sinus gland neurosecretory system of the eyestalks. in studies reported here, we used a pcr-based cloning strategy (rt-pcr followed by 5'- and 3'-race) to clone from blue crab (callinectes sapidus) eyestalk ganglia a cdna (cschh-1) encoding a putative chh preprohormone. sequence analysis revealed the preprohormone included all structural features previously reported for ...200616631756
molecular cloning and characterisation of copper/zinc superoxide dismutase (cu,zn-sod) from the giant freshwater prawn macrobrachium rosenbergii.a copper/zinc superoxide dismutase (cu,zn-sod) cdna was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription-polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by the rapid amplification of cdna ends method. analysis of nucleotide sequence revealed that the cu,zn-sod cdna clone consists of 845 bp with an open reading frame of 603 bp encoding a protein of 201 amino acids with a 22 amino acid sig ...200616356736
effects of eyestalk ablation on carbonic anhydrase activity in the euryhaline blue crab callinectes sapidus: neuroendocrine control of enzyme expression.carbonic anhydrase (ca) activity in the gills of the euryhaline blue crab, callinectes sapidus, was measured in response to acute low-salinity transfer and treatment with eyestalk ablation (esa) in an attempt to elucidate potential regulatory mechanisms of salinity-mediated ca induction. esa alone resulted in an approximate doubling of ca activity in the posterior, ion-transporting gills of crabs acclimated to 35 ppt. transfer of intact crabs to 28 ppt, a salinity at which the blue crab is still ...200616358277
the utilization of lipovitellin during blue crab (callinectes sapidus) embryogenesis.embryos of the blue crab callinectes sapidus develop in egg sacs carried on the abdomen of the female. they develop over a period of 10-13 days at 28 degrees c and are nutritionally dependent on yolk until they emerge from the egg sacs as free-swimming zoeae. the principal component of blue crab yolk is lipovitellin (lpii), a water-soluble lipoprotein composed of approximately equal amounts of lipid and protein. we followed changes in the concentration of apoproteins of lpii during embryogenesis ...200616406827
molecular cloning of a putative receptor guanylyl cyclase from y-organs of the blue crab, callinectes sapidus.crustacean molt-inhibiting hormone (mih), a polypeptide produced by neurosecretory cells in eyestalk ganglia, suppresses the synthesis of ecdysteroid molting hormones by paired y-organs. data from several sources indicate the effects of mih are mediated, at least in part, by a cgmp second messenger. based on these and related findings, our working hypothesis is that the mih receptor is a receptor guanylyl cyclase (rgc). in studies reported here, we used a pcr-based cloning strategy (rt-pcr follo ...200616426608
gill area, permeability and na+ ,k+ -atpase activity as a function of size and salinity in the blue crab, callinectes sapidus.juvenile blue crabs, callinectes sapidus, extensively utilize oligohaline and freshwater regions of the estuary. with a presumptively larger surface-area-to-body weight ratio, juvenile crabs could experience osmo- and ionoregulatory costs well in excess of that of adults. to test this hypothesis, crabs ranging over three orders of magnitude in body weight were acclimated to either sea water (1,000 mosm) or dilute sea water (150 mosm), and gill surface area, water and sodium permeabilities (calcu ...200616432886
regulation of protein synthesis in y-organs of the blue crab (callinectes sapidus): involvement of cyclic amp.paired y-organs secrete ecdysteroid hormones that control cycles of growth and molting in crustaceans. y-organs are regulated, at least in part, by molt-inhibiting hormone (mih), a polypeptide produced and released by the x-organ/sinus gland complex of the eyestalks. in the present studies, crab (callinectes sapidus) y-organs were incubated in vitro in the presence of [(35)s]methionine, and cyclic nucleotide analogs or experimental agents that influence the camp signaling pathway. in 4-hr incuba ...200616493643
two new species of epistylis (ciliophora: peritrichida) on the blue crab (callinectes sapidus) in the gulf of mexico.two epibiotic peritrichs infested the blue crab, callinectes sapidus, from the gulf of mexico, mississippi, usa. epistylis callinectes n. sp. was isolated from the epipods of maxillipeds, bases of gill-cleaning setae, and gills, and epistylis clampi n. sp. was isolated from the exterior surfaces of the exoskeleton. epistylis callinectes has short, symmetrically and dichotomously branched stalks; its zooid is elongate ovoid and conspicuously longer than the individual stalk branches, measuring 40 ...200616579810
hard clams (mercenaria mercenaria) evaluate predation risk using chemical signals from predators and injured conspecifics.hard clams, mercenaria mercenaria, are sessile, filter-feeding organisms that are heavily preyed upon by blue crabs, which find their clam prey using chemical cues. clams may evade blue crabs by reducing their pumping (feeding) behavior when a threat is perceived. the purpose of this study was to determine the type of signals that clams use to detect consumers. clams decreased their pumping time in response to blue crabs and blue crab effluent, but not to crab shells, indicating that chemical si ...200616586040
molecular cloning and characterisation of cytosolic manganese superoxide dismutase (cytmn-sod) from the giant freshwater prawn macrobrachium rosenbergii.a cytosolic manganese superoxide dismutase (cytmn-sod) cdna was cloned from the hepatopancreas of giant freshwater prawn macrobrachium rosenbergii using reverse transcription polymerase chain reaction (rt-pcr) by degenerate primers. both 3'- and 5'-regions were isolated by rapid amplification of cdna end race method. analysis of nucleotide sequence revealed that the cytmn-sod cdna clone consists of 1339 bp with an open reading frame of 858 bp encoding a protein of 286 amino acids. the calculated ...200616154362
expressed sequence tags from normalized cdna libraries prepared from gill and hypodermal tissues of the blue crab, callinectes sapidus.expressed sequence tags (ests) were produced from two normalized cdna libraries from the blue crab, callinectes sapidus. the gill library represented pooled rna from respiratory and transporting gills after acclimation to either high or low salinity. the hypodermis library was from arthrodial and dorsal tissue from both pre- and post-molt crabs. random clones were single-pass sequenced from the 5'-ends, resulting in 11,761 high quality ests averaging 652 bases. all the ests were assembled using ...200620483251
identifying exoskeleton proteins in the blue crab from an expressed sequence tag (est) library.a blue crab (callinectes sapidus) expressed sequence tag project was designed for multiple purposes including discovery of genes for cuticular (exoskeletal) proteins, some of which may regulate mineralization. one of the expression libraries sequenced was from the hypodermis (the epithelium depositing the cuticle). rnas used for cdna synthesis were pooled from arthrodial and mid-dorsal hypodermis at both pre-ecdysis and post-ecdysis. this ensured representation from both calcifying and non-calci ...200621672801
et743: chemical analysis of the sea squirt ecteinascidia turbinata ecosystem.the sea squirt ecteinascidia turbinata produces the powerful drug et743. in this study inductively coupled plasma-atomic emission spectroscopy (icp-aes) and matrix assisted laser desorption ionization-mass spectrometry (maldi-ms) are systematically used to measure elemental and molecular species in a florida keys mangrove ecosystem that contains the sea squirt. icp-aes is used to measure the concentration of 27 elements down to the parts per billion level in 16 organisms and 3 sediment samples t ...200616644544
a review of the parasitic dinoflagellates hematodinium species and hematodinium-like infections in marine crustaceans.parasitic dinoflagellates in the genus hematodinium are important parasites of marine crustacea. outbreaks of these parasites have damaged commercial stocks of norway lobster nephrops norvegicus, snow crab chionoecetes opilio, tanner crab c. bairdi, american blue crab callinectes sapidus, and velvet swimming crab necora puber. species of hematodinium can reach high enough levels to regulate their host populations, but mortalities are also centred on the unfished juveniles and females, hosts not ...200516175968
phylogenetic position of the copepod-infesting parasite syndinium turbo (dinoflagellata, syndinea).sequences were determined for the nuclear-encoded small subunit (ssu) rrna and 5.8s rrna genes as well as the internal transcribed spacers its1 and its2 of the parasitic dinoflagellate genus syndinium from two different marine copepod hosts. syndinium developed a multicellular plasmodium inside its host and at maturity free-swimming zoospores were released. syndinium plasmodia in the copepod paracalanus parvus produced zoospores of three different morphological types. however, full ssu rdna sequ ...200516310746
the decapod crustacean circulatory system: a case that is neither open nor closed.historically, the decapod crustacean circulatory system has been classed as open. however, recent work on the blue crab, callinectes sapidus, suggests the circulatory system may be more complex than previously described. corrosion casting techniques were refined and used to map the circulatory system of a variety of crab species (order: decapoda; family: cancridae) to determine if the complexity observed in the blue crab was present in other species. seven arteries arose from the single chambere ...200515683568
early pattern of calcification in the dorsal carapace of the blue crab, callinectes sapidus.the pattern of calcium carbonate deposition was observed in the dorsal carapace of premolt (d2-d3) and early postmolt (0-48 h) blue crabs, callinectes sapidus, using scanning (sem) and transmission (tem) electron microscopy. samples of dorsal carapace for sem were quick-frozen in liquid nitrogen, subsequently lyophilized, and viewed using secondary and backscattered electrons as well as x-ray maps of calcium. pieces of lyophilized cuticle were also embedded in epoxy resin and subsequently sectio ...200515688443
a comparison of different processing methods for picked blue crab (callinectes sapidus).five methods for producing picked crab meat from cooked blue crab (callinectes sapidus) were evaluated for internal food temperatures and bacterial numbers at various process points. whole shell-on crabs, crab cores ("backed" crabs with carapace removed), and crab meat samples were analyzed for standard plate count, total coliforms, fecal coliforms, escherichia coli, and staphylococcus aureus. for three of the processes, crabs were backed and washed a substantial time before picking; one of the ...200515726982
expression of a serine proteinase homolog prophenoloxidase-activating factor from the blue crab, callinectes sapidus.tanning, or sclerotization, of crustacean cuticle provides initial reinforcement by cross linking cuticular proteins attached to the cuticle chitin-fiber matrix. this process is catalyzed in part by phenoloxidase, which is under the control of a serine protease activation cascade. the cdna of a prophenoloxidase-activating factor (ppaf) was cloned and sequenced from the hypodermal tissue of the blue crab, callinectes sapidus. it codes for a serine proteinase homolog containing a single clip domai ...200515763507
k+-phosphatase activity of gill (na+, k+)-atpase from the blue crab, callinectes danae: low-salinity acclimation and expression of the alpha-subunit.the kinetic properties of a microsomal gill (na(+), k(+)) atpase from the blue crab, callinectes danae, acclimated to 15 per thousand salinity for 10 days, were analyzed using the substrate p-nitrophenylphosphate. the (na(+), k(+))-atpase hydrolyzed the substrate obeying michaelian kinetics at a rate of v=102.9+/-4.3 u.mg(-1) with k(0.5)=1.7+/-0.1 mmol.l(-1), while stimulation by magnesium (v=93.7+/-2.3 u.mg(-1); k(0.5)=1.40+/-0.03 mmol.l(-1)) and potassium ions (v=94.9+/-3.5 u.mg(-1); k(0.5)=2. ...200515776418
isolation and structure elucidation of feeding deterrent diterpenoids from the sea pansy, renilla reniformis.four new briarane diterpenoids, renillins a-d (1-4), and the known compound renillafoulin c (5) were isolated from the sea pansy, renilla reniformis. the structures and relative stereochemistry were elucidated by the interpretation of spectroscopic data. using laboratory feeding assays, all compounds tested at natural concentrations significantly deterred feeding by the predatory lesser blue crab, callinectes similis, while renillins c (3) and d (4) also deterred feeding by the predatory mummich ...200515844939
trimeric g proteins in crustacean (callinectes sapidus) y-organs: occurrence and functional link to protein synthesis.crustacean y-organs produce ecdysteroid molting hormones. regulation of ecdysteroidogenesis appears to be complex, involving regulatory ligands (including but not limited to molt-inhibiting hormone, an eyestalk neurohormone) and the capacity of the y-organs to respond to those ligands. available data indicate cell signaling pathways involving camp, cgmp, or both may be involved in regulation of y-organ function. trimeric g proteins link receptor occupancy to regulation of intracellular camp leve ...200515880757
four differentially expressed cdnas in callinectes sapidus containing the rebers-riddiford consensus sequence.decapod crustaceans such as callinectes sapidus, the blue crab, provide unique opportunities to study proteins involved in biomineralization. subsequent to each molt, the previously deposited soft cuticle is calcified while the postecdysial layers are simultaneously deposited and mineralized. though the majority of the exoskeleton hardens, morphologically similar cuticle at the joints, called arthrodial membrane, remains flexible. it seems reasonable that hypodermal cells producing these cuticle ...200515939643
does intracellular metabolite diffusion limit post-contractile recovery in burst locomotor muscle?post-metamorphic growth in the blue crab entails an increase in body mass that spans several orders of magnitude. the muscles that power burst swimming in these animals grow hypertrophically, such that small crabs have fiber diameters that are typical of most cells (<60 microm) while in adult animals the fibers are giant (>600 microm). thus, as the animals grow, their muscle fibers cross and greatly exceed the surface area to volume ratio (sa:v) and intracellular diffusion distance threshold tha ...200516000534
gill microsomal (na+,k+)-atpase from the blue crab callinectes danae: interactions at cationic sites.euryhaline crustaceans tolerate exposure to a wide range of dilute media, using compensatory, ion regulatory mechanisms. however, data on molecular interactions occurring at cationic sites on the crustacean gill (na+,k+)-atpase, a key enzyme in this hyperosmoregulatory process, are unavailable. we report that na+ binding at the activating site leads to cooperative, heterotropic interactions that are insensitive to k+. the binding of k+ ions to their high affinity sites displaces na+ ions from th ...200516055367
the complete mitochondrial genome of the stomatopod crustacean squilla mantis.animal mitochondrial genomes are physically separate from the much larger nuclear genomes and have proven useful both for phylogenetic studies and for understanding genome evolution. within the phylum arthropoda the subphylum crustacea includes over 50,000 named species with immense variation in body plans and habitats, yet only 23 complete mitochondrial genomes are available from this subphylum.200516091132
critical salinity, sensitivity, and commitment of salinity-mediated carbonic anhydrase induction in the gills of two euryhaline species of decapod crustaceans.two euryhaline species of decapod crustaceans, carcinus maenas and callinectes sapidus, were subjected to a series of acute low-salinity challenges, and changes in carbonic anhydrase (ca) activity in the gills were monitored in order to characterize the nature of salinity-sensitive ca induction. ca activity is uniformly low in all gills of both species at high salinity, but at a critical salinity of 27 ppt, ca induction occurs in the posterior, ion-transporting gills, with ca activity approximat ...200515612006
superoxide dismutase evolution and life span regulation.superoxide is among the most abundant reactive oxygen species (ros) produced by the mitochondria, and is involved in cellular signaling pathways. superoxide and other ros can damage cellular macromolecules and levels of oxidative damage products are positively correlated with aging. superoxide dismutase (sod) enzymes catalyze the breakdown of superoxide into hydrogen peroxide and water and are therefore central regulators of ros levels. genetic and transgenic manipulation of sod activities in mo ...200515664623
incremental ecological exposure risks from contaminated sediments in an urban estuarine river.estuaries in urban regions present unique environmental management challenges. ecosystems in urban estuaries are typically impacted by habitat loss and degradation, watershed modification, and nonpoint and point sources of many chemicals. restoring such systems requires an understanding of the relative contribution of various stressors to overall ecological conditions and an understanding of shifting patterns of stress over time. in this article, we present the results of a multiparameter enviro ...200516639904
ultrastructure, histochemistry, and mineralization patterns in the ecdysial suture of the blue crab, callinectes sapidus.the ecdysial suture is the region of the arthropod exoskeleton that splits to allow the animal to emerge during ecdysis. we examined the morphology and composition of the intermolt and premolt suture of the blue crab using light microscopy and scanning electron microscopy. the suture could not be identified by routine histological techniques; however 3 of 22 fluorescein isothiocyanate-labeled lectins tested (lens culinaris agglutinin, vicia faba agglutinin, and pisum sativum agglutinin) differen ...200517481327
exuviotrophic apostome ciliates from crustaceans of st. andrew bay, florida, and a description of gymnodinioides kozloffi n. sp.gymnodinioides kozloffi n. sp. is described from the eelgrass broken-back shrimp hippolyte zostericola. the species is distinct from others in the apostome genus gymnodinioides in that the trophont ciliature has a small group of kinetosomes located to the right of kinety 9a, and kinety 1 and 2 are divided. other apostome morphologies are described from many decapod crustaceans from st. andrew bay, florida, including gymnodinioides inkystans, hyalophysa chattoni, and variants of both h. chattoni ...200415666721
the lipid composition of hypodermal membranes from the blue crab (callinectes sapidus) changes during the molt cycle and alters hypodermal calcium permeability.crustaceans are covered by a cuticle that does not grow. in order for an individual to grow, the cuticle must periodically be shed (ecdysis). replacement of the old cuticle with a new one depends on processes that require precise timing and control, yet the nature and location of these controls remain unclear. a candidate site for them is within the hypodermal microvilli. these cellular structures extend through pore canals deep into the acellular cuticular matrix. changes in the lipid compositi ...200414990220
metabolic influences of fiber size in aerobic and anaerobic locomotor muscles of the blue crab, callinectes sapidus.diameters of some white locomotor muscle fibers in the adult blue crab, callinectes sapidus, exceed 500 microm whereas juvenile white fibers are <100 microm. it was hypothesized that aerobically dependent processes, such as metabolic recovery following burst contractions, will be significantly impeded in the large white fibers. in addition, dark aerobic fibers of adults, which rely on aerobic metabolism for both contraction and recovery, grow as large as the white fibers. these large aerobic fib ...200415498950
evaluation of a florida coastal golf complex as a local and watershed source of bioavailable contaminants.contaminant fate in coastal areas impacted by golf course runoff is not well understood. this report summarizes trace metal, pesticide and pcb residues for colonized periphyton, ruppia maritima (widgeon grass), callinectes sapidus rathbun (blue crabs) and crassostrea virginica gemlin (eastern oyster) collected from areas adjacent to a florida golf course complex which receive runoff containing reclaimed municipal wastewater. concentrations of 19 chlorinated pesticides and 18 pcb congeners were u ...200414972577
ecological risk assessment of neem-based pesticides.a tiered process was used to evaluate the risks of pure azadirachtin (aza) and two neem-based insecticides (neemix and bioneem) on six aquatic animals [crayfish (procambarus clarkii), white shrimp (penaeus setiferus), grass shrimp (palaemonetes pugio), blue crabs (callinectes sapidus), water fleas (daphnia pulex), and mosquito larvae (culex quinquefasciatus)] through short term acute toxicity tests. the risk was calculated using the level of concern endpoints (q values) and relative hazard index ...200415132337
environmentally-controlled, density-dependent secondary dispersal in a local estuarine crab population.the mechanisms driving the pelagic secondary dispersal of aquatic organisms following initial settlement to benthic habitats are poorly characterized. we examined the physical environmental (wind, diel cycle, tidal phase) and biological (ontogenetic, density-dependent) factors that contribute to the secondary dispersal of a benthic marine invertebrate, the blue crab (callinectes sapidus) in pamlico sound, nc, usa. field studies conducted in relatively large (0.05 km2) seagrass beds determined th ...200415146323
effects of hypoxia on gene and protein expression in the blue crab, callinectes sapidus.increases in hypoxic conditions are one of the major factors responsible for declines in estuarine habitat quality, yet to date there are no indicators for recognizing populations of estuarine organisms that are suffering from chronic hypoxic stress. here we test the hypothesis that alterations in gene and protein expression of antioxidant enzymes and other stress-specific proteins can be used as molecular indicators of hypoxic stress. blue crabs, callinectes sapidus, were exposed to 2-3 ppm do ...200415178114
effects of hypercapnic hypoxia on the clearance of vibrio campbellii in the atlantic blue crab, callinectes sapidus rathbun.callinectes sapidus, the atlantic blue crab, encounters hypoxia, hypercapnia (elevated co(2)), and bacterial pathogens in its natural environment. we tested the hypothesis that acute exposure to hypercapnic hypoxia (hh) alters the crab's ability to clear a pathogenic bacterium, vibrio campbellii 90-69b3, from the hemolymph. adult male crabs were held in normoxia (well-aerated seawater) or hh (seawater with po(2) = 4 kpa; pco(2) = 1.8 kpa; and ph = 6.7-7.1) and were injected with 2.5 x 10(4) vibr ...200415198944
purification of a soluble glycoprotein from the uncalcified ecdysial cuticle of the blue crab callinectes sapidus and its possible role in initial mineralization.a heavily glycosylated soluble protein was purified using a combination of lectin affinity and size exclusion chromatography from a soluble extract of uncalcified dorsal cuticle of blue crab callinectes sapidus removed at ecdysis. similarities in apparent molecular mass and carbohydrate composition suggest that this protein is the same species previously shown to disappear from soluble extracts coincidentally with the onset of mineral deposition in the newly exposed post-molt cuticle. the amino ...200415201291
haemolymph parasite of the shore crab carcinus maenas: pathology, ultrastructure and observations on crustacean haplosporidians.a protozoan parasite with some features of haplosporidians is described from the european shore crab carcinus maenas. the parasite establishes a systemic infection through the haemal sinuses and connective tissues. intracellular stages of the parasite were found within reserve inclusion, connective tissue, and muscle cells, while free forms were present in all haemal spaces. a uninucleate stage appeared to develop to a multinucleate plasmodial stage following multiple mitotic divisions of the nu ...200415212293
modulation of an integrated central pattern generator-effector system: dopaminergic regulation of cardiac activity in the blue crab callinectes sapidus.theoretical studies have suggested that the output of a central pattern generator (cpg) must be matched to the properties of its peripheral effector system to ensure production of functional behavior. one way that such matching could be achieved is through coordinated central and peripheral modulation. in this study, morphological and physiological methods were used to examine the sources and actions of dopaminergic modulation in the cardiac system of the blue crab, callinectes sapidus. immunohi ...200415295014
effects of odor flux and pulse rate on chemosensory tracking in turbulent odor plumes by the blue crab, callinectes sapidus.the ability of animals to track through chemical plumes is often related to properties of evanescent odor bursts and to small-scale mixing process that determine burst properties. however, odor plumes contain variation over a range of scales, and little is known about how variation in the properties of the odor signal on the scale of one to several seconds affects foraging performance. we examined how flux and pulse rate interact to modulate the search behavior of blue crabs, callinectes sapidus ...200415315942
structural basis for salinity-induced alteration in oxygen binding by haemocyanin from the estuarine amphipod chaetogammarus marinus (l.).in the estuarine amphipod chaetogammarus marinus, differences in o(2) binding by haemocyanins (hc) could be related to natural and salinity-related quantitative variation in just one polypeptide subunit (band 2) and not to variations in any of the other seven bands present. band 2 was always present, irrespective of salinity treatment, and naturally makes up 6%-36% of the total hc. however, low salinity exposure (s=4 per thousand for 48-49 h, t=15 degrees c) was accompanied by an increase in the ...200314988799
fluid mechanics produces conflicting, constraints during olfactory navigation of blue crabs, callinectes sapidus.foraging blue crabs must respond to fluid forces imposed on their body while acquiring useful chemical signals from turbulent odor plumes. this study examines how blue crabs manage these simultaneous demands. the drag force, and hence the cost of locomotion, experienced by blue crabs is shown to be a function of the body orientation angle relative to the flow. rather than adopting a fixed orientation that minimizes the drag, blue crabs decrease their relative angle (increase drag) when odor is p ...200312456707
fish tissue quality in the lower mississippi river and health risks from fish consumption.between 1990 and 1994, samples of three shellfish species (i.e. blue crab, callinectes sapidus;crayfish, procambarus acutis; and river shrimp, macrobrachium ohionii) and 16 fish species and were collected at six sites along the lower mississippi river by the louisiana department of environmental quality, office of water resources in coordination with the us environmental protection agency. the fish species included: bigmouth buffalo (ictiobus cyanellus); blue catfish (ictalurus furcatus); carp ( ...200312526903
synthesis of a high-density lipoprotein in the developing blue crab (callinectes sapidus).an important lipoprotein in the hemolymph of crustaceans is lpi. it transports lipid to peripheral tissues and also has a role in crustacean immune recognition. we employed a monoclonal antibody specific for the lpi peptide to demonstrate by elisa, western blot and immunohistochemistry the appearance of lpi during development of callinectes sapidus, the blue crab. lpi was first found in stage 5 embryos and appeared to be synthesized by lateral basophilic cuboidal cells that demonstrated cytoplas ...200312588744
formation of the arthrodial membrane in the blue crab, callinectes sapidus.in this study the pattern of arthrodial membrane deposition in callinectes sapidus was determined by histological and ultrastructural examination of tissues from the carpus joint of the cheliped collected during premolt, ecdysis, postmolt, and intermolt. apolysis in the arthrodial membrane occurs at stage d(0) and is synchronous with apolysis of the calcified cuticle. epicuticle formation begins at early stage d(1) and is completed in late stage d(1). procuticle deposition starts at d(2) and con ...200312655609
gill (na+,k+)-atpase from the blue crab callinectes danae: modulation of k+-phosphatase activity by potassium and ammonium ions.the kinetic properties of a microsomal gill (na(+),k(+))-atpase from the blue crab callinectes danae were analyzed using the substrate p-nitrophenylphosphate. the (na(+),k(+))-atpase hydrolyzed pnpp obeying cooperative kinetics (n=1.5) at a rate of v=125.4+/-7.5 u mg(-1) with k(0.5)=1.2+/-0.1 mmol l(-1); stimulation by potassium (v=121.0+/-6.1 u mg(-1); k(0.5)=2.1+/-0.1 mmol l(-1)) and magnesium ions (v=125.3+/-6.3 u mg(-1); k(0.5)=1.0+/-0.1 mmol l(-1)) was cooperative. ammonium ions also stimul ...200312670789
scaling of gill metabolic potential as a function of salinity in the euryhaline crab, callinectes sapidus rathbun.the body-size scaling pattern of enzymes that are important in energy metabolism was examined in gills of the blue crab as a function of acclimation salinity. we hypothesized that the higher surface-area-to-volume ratio of small crabs would impose a greater metabolic cost for hyperosmoregulation, leading to an increase in the capacity for atp production in gills. postmetamorphic crabs spanning a 2,500-fold range in body mass were examined following a 7-d exposure to a salinity of 35, 17, or 5 pp ...200312695991
the presence and antimicrobial susceptibilities of human-pathogen vibrio spp. isolated from blue crab (callinectes sapidus) in belek tourism coast, turkey.monitoring of vibrio species by blue crabs (callinectes sapidus) was carried out during the winter period in a selected area of the belek, antalya gulf. eighty-three blue crabs were examined for vibrio species. v. alginolyticus (30.1%), v. fluvialis (10.8%), v. damsela (9.6%), v. harveyi (3.6%), v. metschnikovii (3.6%) and v. vulnificus (2.4%) were isolated. v. vulnificus was the highest concentration (5 x 10(8) vibrio ml(-1)) although it was only 2.4% isolated from blue crabs. the strains of di ...200312745351
replacement of a cytosolic copper/zinc superoxide dismutase by a novel cytosolic manganese superoxide dismutase in crustaceans that use copper (haemocyanin) for oxygen transport.the blue crab, callinectes sapidus, which uses the copper-dependent protein haemocyanin for oxygen transport, lacks the ubiquitous cytosolic copper-dependent enzyme copper/zinc superoxide dismutase (cu,znsod) as evidenced by undetectable levels of cu,znsod activity, protein and mrna in the hepatopancreas (the site of haemocyanin synthesis) and gills. instead, the crab has an unusual cytosolic manganese sod (cytmnsod), which is retained in the cytosol, because it lacks a mitochondrial transit pep ...200312769817
coastal seas as a context for science teaching: a lesson from chesapeake bay.lessons that employ authentic environmental data can enhance the ability of students to understand fundamental science concepts. this differs from traditional "environmental education" in that school curricula need not set aside time for educators to teach only environmental topics. rather, the "environment" is used to advance student learning in science and technology. the success of this approach depends on programs that encourage scientists to communicate more effectively with teachers at all ...200312787628
the effects of rapid salinity change on in vivo arginine kinase flux in the juvenile blue crab, callinectes sapidus.the effect of acclimation salinity and salinity changes on the concentration of high-energy phosphate metabolites and arginine kinase (ak) flux was examined in vivo in juvenile blue crabs using 31p-nuclear magnetic resonance (nmr). crabs were acclimated for 7 days to a salinity of 5 or 35 per thousand and then placed in a flow apparatus that could sustain the animals while nmr spectra were acquired. crabs were subjected to either hyperosmotic salinity changes, where an animal acclimated to 5 per ...200312831772
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