Publications

mitochondrial distribution and glycogen dynamics suggest diffusion constraints in muscle fibers of the blue crab, callinectes sapidus.	the scaling of mitochondrial distribution, citrate synthase activity, and post-contractile glycogen recovery was examined in muscle fibers of the blue crab, callinectes sapidus. the fast-twitch muscle fibers of c. sapidus can reach extremely large dimensions, which may impose constraints on aerobic metabolic processes. however, muscle cells from small crabs are not giant, meaning that during development muscle fibers cross and greatly exceed the surface area to volume (sav) and diffusion thresho ...	2003	12911109
mercury accumulation and flux across the gills and the intestine of the blue crab (callinectes sapidus).	this paper details the results of perfusion experiments examining the accumulation of inorganic and methylmercury (hg and mmhg) into the gill and intestine tissue of the blue crab, callinectes sapidus. additionally, the flux across the tissue to an internal medium, representative of crab tissue or haemolymph, during the perfusion was also measured. the accumulation and transfer processes were studied for each form by exposing the organs to a wide range of hg and mmhg water concentrations, as wel ...	2002	11856578
effect of ligands and other metals on the uptake of mercury and methylmercury across the gills and the intestine of the blue crab (callinectes sapidus).	using the perfusion method, we compared the accumulation and flux of inorganic mercury (hg) and methylmercury (ch(3)hg) across the gills and intestine of the blue crab, callinectes sapidus. the accumulation and transfer processes were studied for each form by exposing the organs in the presence of specific ligands and other metals. while binding of hg and ch(3)hg to organic ligands reduced the rate of uptake in most instances, the differences in accumulation could not be explained only in terms ...	2002	11879786
the genomic organization of the open reading frame of the red pigment concentrating hormone gene in the blue crab callinectes sapidus.	the open reading frame (orf) of the gene for the precursor of the octapeptide red pigment concentrating hormone (rpch) from the blue crab callinectes sapidus was cloned by pcr with oligonucleotides targeted to the initiation and the end of the translation coding sequences. a 272 bp intron was characterized between nucleotides 343 and 344 of the reported cdna, present in the region coding for the last amino acids of the precursor related peptide of rpch. the intron genomic structure here describe ...	2002	11897398
toxicity of methyl tert-butyl ether to marine organisms: ambient water quality criteria calculation.	in response to increasing concerns over the detection of methyl tert-butyl ether (mtbe) in groundwater and surface water and its potential effects in aquatic ecosystems, industry and the united states environmental protection agency (usepa) began to collaborate in 1997 to develop aquatic toxicity databases sufficient to derive ambient water quality criteria for mtbe consistent with usepa requirements. acute toxicity data for seven marine species, chronic toxicity data for an invertebrate, and pl ...	2002	11996128
osmotic effects on arginine kinase function in living muscle of the blue crab callinectes sapidus.	flux was examined through the reaction catalyzed by arginine kinase in intact blue crab (callinectes sapidus) muscle during simulated changes in salinity. isolated dark levator muscles from the swimming leg were superfused with a saline solution that had an osmolarity equivalent to that of the hemolymph under different salinity regimes. animals were acclimated for 7 days to a salinity of 5, 17 or 35 per thousand, which corresponds to a hemolymph osmolarity of 640, 720 or 960 mosmoll(-1), respect ...	2002	12042336
antipeptide antibodies for detecting crab (callinectes sapidus) molt-inhibiting hormone.	in crustaceans, the synthesis of ecdysteroid molting hormones is regulated by molt-inhibiting hormone (mih), a neuropeptide produced by an eyestalk neuroendocrine system, the x-organ/sinus gland complex. using sequence analysis software, two regions of the blue crab (callinectes sapidus) mih peptide were selected for antibody production. two 14-mer peptides were commercially synthesized and used to generate polyclonal antisera. western blot analysis revealed that each antiserum bound to proteins ...	2002	12084515
development of an 18s rrna gene-targeted pcr-based diagnostic for the blue crab parasite hematodinium sp..	the 18s rrna gene from hematodinum sp., a parasitic dinoflagellate that infects blue crabs, was amplified, cloned, and sequenced. the sequence showed a high similarity (95% at the nucleotide level) to sequences obtained from other dinoflagellate species, including both free-living and symbiotic species. sequence similarity was much lower when compared with parasites of other marine invertebrates with similar life histories and with the 18s rrna gene from the blue crab. based on comparison of seq ...	2002	12093043
a trophic cascade regulates salt marsh primary production.	nutrient supply is widely thought to regulate primary production of many ecosystems including salt marshes. however, experimental manipulation of the dominant marsh grazer (the periwinkle, littoraria irrorata) and its consumers (e.g., blue crabs, callinectes sapidus, terrapins, malaclemys terrapin) demonstrates plant biomass and production are largely controlled by grazers and their predators. periwinkle grazing can convert one of the most productive grasslands in the world into a barren mudflat ...	2002	12149475
behavioral observations and computer simulations of blue crab movement to a chemical source in a controlled turbulent flow.	the behavior of crabs tracking odor in turbulent chemical plumes was compared to the performance of computer simulations of search behavior operating in similar chemical signal environments. the movement of blue crabs (callinectes sapidus) towards a source of food odor was studied in controlled flow conditions in a flume. the evolving chemical stimulus field of a similar chemical source in an equivalent flow environment was captured by recording concentration patterns of a fluorescent tracer. hy ...	2002	12324548
orientation of the fiddler crab, uca cumulanta: responses to chemical and visual cues.	behavioral responses of the fiddler crab uca cumulanta to flat geometric shapes mimicking natural objects were measured in a circular arena by using zonal recovery as a behavioral measurement. crabs were tested either in presence or absence of odors from two common predator species, the blue crab callinectes sapidus, and the pufferfish sphoeroides testudineus. the study tested the hypothesis that u. cumulanta have different behavioral responses to visual cues in the presence of chemical cues ass ...	2002	12449506
inhibition of carbonic anhydrase in the gills of two euryhaline crabs, callinectes sapidus and carcinus maenas, by heavy metals.	two subcellular fractions of gill tissue, cytoplasm and basolateral membranes, from two species of euryhaline decapod crustaceans, callinectes sapidus and carcinus maenas, acclimated to low salinity, were isolated via differential centrifugation. carbonic anhydrase activity from both fractions was titrated against a variety of heavy metals in vitro. the metals ag(+), cd(2+), cu(2+) and zn(+) showed inhibitory action against the enzyme. ki values for these metals against cytoplasmic ca from c. sa ...	2002	12458188
cardiovascular system of the blue crab callinectes sapidus.	the circulatory system of adult blue crabs, callinectes sapidus, was mapped by either injecting barium sulfate into intact animals followed by radiography or by resin corrosion casts (batsons monomer). seven arteries arise from the heart. the anterior aorta exits from the anterior dorsal surface of the heart and gives rise to the optic arteries; these arteries supply hemolymph to the supraesophageal ganglion and eyestalks. the paired anterolateral arteries also exit from the anterior dorsal surf ...	2002	11746465
expression of crustacean (callinectes sapidus) molt-inhibiting hormone in insect cells using recombinant baculovirus.	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 insect cells using recombinant baculovirus. insect sf9 cells were transfected with recombinant baculovirus containing a dna insert encoding the c. sapidus mih prohormone (signal sequence plus mature hormone). the construct was designed to yield a mature, fully processed recombinant mih (recmih). several ba ...	2002	11754021
role of a copper-specific metallothionein of the blue crab, callinectes sapidus, in copper metabolism associated with degradation and synthesis of hemocyanin.	we have identified three mt encoding genes in the blue crab: mt-i, inducible by cadmium, zinc and copper; mt-ii, inducible by cadmium and zinc; and mt-iii, inducible by copper only [syring et al., comp. biochem. physiol. c, 125 (2000) 325-332]. to examine the role of the cumt-i and cumt-iii isoforms in copper metabolism associated with the synthesis and degradation of the oxygen-binding copper protein, hemocyanin, we (1) cloned and sequenced hemocyanin cdna, (2) examined interaction of the cumts ...	2002	11803044
na(+)+k(+)-atpase in gills of the blue crab callinectes sapidus: cdna sequencing and salinity-related expression of alpha-subunit mrna and protein.	many studies have shown that hyperosmoregulation in euryhaline crabs is accompanied by enhanced na(+)+k(+)-atpase activity in the posterior gills, but it remains unclear whether the response is due to regulation of pre-existing enzyme or to increased gene transcription and mrna translation. to address this question, the complete open reading frame and 3' and 5' untranslated regions of the mrna coding for the alpha-subunit of na(+)+k(+)-atpase from the blue crab callinectes sapidus were amplified ...	2001	11807118
sequencing and amplified restriction fragment length polymorphism analysis of ribonucleotide reductase large subunit gene of the white spot syndrome virus in blue crab (callinectes sapidus) from american coastal waters.	in the present study, the existence of white spot syndrome virus (wssv) in blue crab (callinectes sapidus) collected from 3 different american coastal waters (new york, new jersey, and texas) was confirmed by 2-step diagnostic polymerase chain reaction and in situ hybridization analysis. when geographic isolates were also compared using a gene that encodes the wssv ribonucleotide reductase large subunit rr1 (wssv rr1), a c(1661)-to-t point mutation was found in the new jersey wssv isolated. this ...	2001	14961379
novel subcellular and molecular tools to study ca(2+) transport mechanisms during the elusive moulting stages of crustaceans: flow cytometry and polyclonal antibodies.	our understanding of calcium homeostasis during the crustacean moulting cycle derives from research on intermoult animals that has been extrapolated to other stages. in terms of transepithelial ca(2+) flux, the more interesting stages are those surrounding ecdysis since crustaceans experience a sizeable negative calcium balance in immediate premoult and a significant positive calcium balance in immediate postmoult. these stages are elusive in the sense that larger species such as lobsters are ra ...	2001	11171419
factors influencing planktonic, post-settlement dispersal of early juvenile blue crabs (callinectes sapidus rathbun).	an emerging body of literature points to post-settlement, planktonic dispersal as a key determinant of distribution and abundance patterns of aquatic organisms, yet little is known about mechanisms inducing such dispersal. recent evidence suggests that early juvenile blue crabs (callinectes sapidus rathbun) may use planktonic emigration as a means of post-settlement dispersal. the goal of this study was to identify mechanisms inducing post-settlement, planktonic dispersal of early juvenile blue ...	2001	11245875
effects of periodic hypoxia on mortality, feeding and predation in an estuarine epifaunal community.	the york river estuary, a tributary of the chesapeake bay, usa, experiences periodic low oxygen stress (hypoxia), yet epifaunal species form dense communities there. we studied hypoxia tolerance of common epifaunal species in the york river by exposing sessile and mobile epifauna to high and low oxygen concentrations in laboratory aquaria. mortality in hypoxia varied among species, ranging from 0% to 100%, with trends of decreased tolerance by mobile species relative to sessile species. while mo ...	2001	11278013
glycosidase activity in the post-ecdysial cuticle of the blue crab, callinectes sapidus.	we have previously demonstrated a marked change in sugar moieties of glycoproteins of the cuticle of the blue crab, callinectes sapidus, between 0.5 and 3 h post-ecdysis. the present study has identified a glycosidase that appears in the cuticle during the early post-ecdysial hours. the enzyme has affinities for p-nitrophenyl derivatives of both n-acetylglucosamine and n-acetylgalactosamine. both activities are competitively inhibited by chitobiose, suggesting that the enzyme could be a n-acetyl ...	2001	11290450
effects of exogenous n-acetylhexosaminidase on the structure and mineralization of the post-ecdysial exoskeleton of the blue crab, callinectes sapidus.	a cuticular glycosidase with characteristics of n-acetyl-beta-d-hexosaminidase (hexnacase) was identified in post-ecdysial crab cuticle. its appearance coincided with changes in cuticular glycoproteins and the onset of mineralization. to test if hexnacase might be the causative agent in the alteration of the glycans and initiation of calcification, newly molted crab cuticle was treated with exogenous hexnacase. treating cuticular extracts from crabs at 0 h post-ecdysis with exogenous hexnacase m ...	2001	11290451
early carbonic anhydrase induction in the gills of the blue crab, callinectes sapidus, during low salinity acclimation is independent of ornithine decarboxylase activity.	carbonic anhydrase (ca) induction in the gills of the euryhaline blue crab, callinectes sapidus, was measured in response to lowered environmental salinity. simultaneous measurements of ornithine decarboxylase (odc) activity were made in gills and nonbranchial tissues to determine whether odc activity and the resultant synthesis of polyamines played a role in the initiation and regulation of ca induction. ca induction in the seventh gill pair (g7) was proportional to the decrease in ambient sali ...	2001	11351322
exposure assessment of dioxins/furans consumed in dairy foods and fish.	dioxins/furans are ubiquitous environmental contaminants whose primary route of human exposure occurs via the consumption of fatty foods of animal origin. the us fda conducted a market basket survey of dairy products and commercial fish and shellfish to obtain data on levels of 17 dioxin/furan congeners (2, 3, 7, 8-congeners) in the us. the dairy products sampled included various cheeses (american, cheddar, swiss, cottage), ice cream, yogurt, butter, and milk. the finfish and shellfish (molluscs ...	2001	11358181
quadrupole ion storage tandem mass spectrometry and high-resolution mass spectrometry: complementary application in the measurement of 2,3,7,8-chlorine substituted dibenzo-p-dioxins and dibenzofurans in us foods.	the us food and drug administration has simultaneously utilized both high-resolution mass spectrometry (hrms) and quadrupole ion storage tandem mass spectrometry (qistms) in the measurement of polychlorinated dibenzo-p-dioxins/dibenzofurans (pcdd/fs) in 147 food samples collected in 1998 and 1999 in the us. in 1998, 20 egg samples, six scallop, 10 blue crab, eight american lobster, 10 pollack, 15 striped bass, five rockfish, 10 crawfish, seven aqua-cultured and 13 wild-caught salmon, along with ...	2001	11372820
effects of anabaena spiroides (cyanobacteria) aqueous extracts on the acetylcholinesterase activity of aquatic species.	the effects of aqueous extracts from a cyanobacteria species, anabaena spiroides, on fish (odontesthes argentinensis), crab (callinectes sapidus), and purified eel acetylcholinesterase (ache) activity were studied. in vitro concentrations of a. spiroides aqueous extract that inhibited 50% of enzyme activity (ic50) were 23.0, 17.2, and 45.0 mg/l of lyophilized cyanobacteria for eel, fish, and crab ache, respectively. eel ache inhibition follows pseudo-first-order kinetics, the same expected for o ...	2001	11392132
carbonic anhydrase isozyme distribution and characterization in metabolic fiber types of the dorsal levator muscle of the blue crab, callinectes sapidus.	carbonic anhydrase (ca) distribution and characterization were examined in white and light pink fibers of the dorsal levator muscle of the blue crab. white fibers were structurally and metabolically characterized as fast twitch glycolytic, while the light pink fibers were fast oxidative. all subcellular fractions of both fiber types had significant levels of ca activity; cytoplasmic and microsomal activity was significantly higher in light pink vs white fibers. cytoplasmic ca from both fiber typ ...	2001	11479903
flux of heavy metal accumulation in various organs of the intertidal marine blue crab, portunus pelagicus (l.) from the kuwait coast after the gulf war.	the metal levels of arsenic, chromium, copper, lead, magnesium, manganese, selenium, vanadium, and zinc concentrations were determined in various body organs, viz., hepatopancreas, gills, gonad, gastric stomach, and muscle of the blue crab, portunus pelagicus (crustacea: decapoda) to assess the bioaccumulation of metals associated with petroleum input a decade after the 1991 gulf war oil spillage. sample solutions prepared were analyzed using an atomic absorption spectrophotometry. high concentr ...	2001	11686643
identification and ultrastructural characterization of a novel virus from fish.	during routine investigations on fish, a virus (isolate df 24/00) with novel morphological features and hitherto undescribed morphogenesis was isolated from a white bream (blicca bjoerkna l.; teleostei, order cypriniformes). cell-free virions consist of a rod-shaped nucleocapsid (120-150x19-22 nm) similar to that seen in baculoviruses. the virion has a bacilliform shape (170-200x75-88 nm) reminiscent of rhabdoviruses with an envelope containing coronavirus-like spikes (20-25 nm). df 24/00 replic ...	2001	11714959
molt-inhibiting hormone immunoreactive neurons in the eyestalk neuroendocrine system of the blue crab, callinectes sapidus.	the production of ecdysteroid molting hormones by crustacean y-organs is negatively regulated by a neuropeptide, molt-inhibiting hormone. it is generally agreed that molt-inhibiting hormone is produced and released by the eyestalk neuroendocrine system. in the present study, immunocytochemical methods were used to detect molt-inhibiting hormone immunoreactive neurons in eyestalk ganglia of the blue crab, callinectes sapidus. the primary antiserum used was generated against molt-inhibiting hormon ...	2001	18088946
trophic accumulation and depuration of mercury by blue crabs (callinectes sapidus) and pink shrimp (penaeus duorarum).	mercury concentrations in blue crabs (callinectes sapidus) collected from an area of mercury-contaminated sediments in lavaca bay, tx, usa, are more than an order of magnitude greater than concentrations in penaeid shrimp from the same area. laboratory feeding experiments using mercury-contaminated fish as food showed that both blue crabs and pink shrimp (penaeus duorarum) could accumulate mercury concentrations comparable to those in their food in 28 days. calculated mercury assimilation effici ...	2000	11285721
integrated physiological responses to feeding in the blue crab callinectes sapidus.	the passage of a barium meal (15 % by mass) was followed through the digestive system of the blue crab callinectes sapidus by flash-freezing crabs at set intervals, followed by radiography of specimens. food moved from the oesophagus into the stomach region within 15 min. after 1-2 h, food was visible in the midgut, at 6 h it had reached the hindgut, and material was still present in the stomach at this time. the stomach was emptied between 8 and 10 h after feeding, and the entire digestive syst ...	2000	10607545
electrospray ionization mass spectrometry of zinc, cadmium, and copper metallothioneins: evidence for metal-binding cooperativity.	electrospray ionization (esi) mass spectra of both well-characterized and novel metallothioneins (mts) from various species were recorded to explore their metal-ion-binding modes and stoichiometries. the esi mass spectra of the zinc- and cadmium-binding mts showed a single main peak corresponding to metal-to-protein ratios of 4, 6, or 7. these findings combined with data obtained by other methods suggest that these mts bind zinc or cadmium in a single predominant form and are consistent with the ...	2000	10716192
reproductive ecology of the blue crab, callinectes danae smith, 1869 in the conceição lagoon system, santa catarina isle, brazil.	abundance of ovigerous females, size of the first gonadal maturation and the possible migration, route of the blue crab callinectes danae from the conceição lagoon system, santa catarina isle, brazil, are described. this lagoon is connected with the coastal area through a canal. a total of 1,124 crabs was caught during a 19 month sampling period. the reproduction and recruitment of juveniles occurred all year-round, with two peaks of abundance (february and september), correlated with the presen ...	2000	10838920
expression of arginine kinase enzymatic activity and mrna in gills of the euryhaline crabs carcinus maenas and callinectes sapidus.	phosphagen kinases catalyze the reversible dephosphorylation of guanidino phosphagens such as phosphocreatine and phosphoarginine, contributing to the restoration of adenosine triphosphate concentrations in cells experiencing high and variable demands on their reserves of high-energy phosphates. the major invertebrate phosphagen kinase, arginine kinase, is expressed in the gills of two species of euryhaline crabs, the blue crab callinectes sapidus and the shore crab carcinus maenas, in which ene ...	2000	10903154
crab stomach pyloric muscles display not only excitatory but inhibitory and neuromodulatory nerve terminals.	movements of the foregut in crustaceans are produced by striated muscles that are innervated by motor neurons in the stomatogastric ganglion (stg). firing of the stg motor neurons generates excitatory junctional potentials (ejps) in the stomach muscles. we now provide evidence for the existence of separate inhibitory and neuromodulatory innervations of some pyloric muscles in the foregut of several crabs, callinectes sapidus, cancer magister, and cancer borealis. electron microscopic examination ...	2000	10940943
polychlorinated naphthalenes in soil, sediment, and biota collected near a former chloralkali plant in coastal georgia, usa.	concentrations of total polychlorinated naphthalenes (pcns) as high as 23 micrograms/g, dry wt, were found in sediments contaminated by the disposal of wastes from chlor-alkali processes. concentrations of total pcns in blue crab, fish and birds were 3- to 5-orders of magnitude less than that in sediments. the profile of pcn congeners in biota was predominated by tetra- or penta-chloronaphthalenes, while hepta- and octa-chloronaphthalenes were dominant in sediments. the 2,3,7,8-tetrachlorodibenz ...	2000	10943435
predator-prey relations between age-1+ summer flounder (paralichthys dentatus, linnaeus) and age-0 winter flounder (pseudopleuronectes americanus, walbaum): predator diets, prey selection, and effects of sediments and macrophytes.	laboratory experiments and weekly trammel net surveys in the navesink river, new jersey (usa) were used to examine the predator-prey interaction between age-1+ summer flounder (paralichthys dentatus) and age-0 winter flounder (pseudopleuronectes americanus). winter flounder (24-67 mm tl) were the dominant piscine prey of summer flounder (n=95, 252-648 mm tl) collected in trammel nets. we observed a temporal shift in summer flounder diets from sand shrimp (crangon septemspinosa) and winter flound ...	2000	10958899
sustaining olfaction at low salinities: evidence for a paracellular route of ion movement from the hemolymph to the sensillar lymph in the olfactory sensilla of the blue crab callinectes sapidus.	evidence reported previously suggests that in low-salinity conditions the integrity of the olfactory dendrites of the blue crab is sustained by a diffusion-generated ionic microenvironment within the aesthetascs. diffusion of ions from the hemolymph to the sensillar lymph is proposed to maintain this microenvironment. in this study, using lanthanum as an electron-dense marker of extracellular fluid space, we find morphological evidence for paracellular continuity between the hemolymph and the se ...	2000	10994788
sustaining olfaction at low salinities: mapping ion flux associated with the olfactory sensilla of the blue crab callinectes sapidus.	to test the hypothesis of a diffusion-generated, ionic/osmotic microenvironment within the olfactory sensilla (aesthetascs), flux gradients of ca(2+) and k(+) associated with the external surfaces of these sensilla were spatially mapped using self-referencing, ion-selective microelectrodes. blue crabs (callinectes sapidus) acclimated to low-salinity conditions (15% sea water and fresh water) showed a net efflux of ions from the aesthetascs. the region of maximum flux associated with each aesthet ...	2000	11003825
broad antiviral activity in tissues of crustaceans.	innate antiviral substances occur in vertebrates and may function as host defenses. virus infections are common among invertebrates, but little is known about the ability of invertebrates to control viral infections. pre-existing antiviral substances may be particularly important, since invertebrates lack the antiviral defense conferred by specific immunity. in our study, we found that tissue extracts of blue crab (callinectes sapidus), shrimp (penaeus setiferus), and crayfish (procambarus clark ...	2000	11080539
purification of vitellin from grass shrimp palaemonetes pugio, generation of monoclonal antibodies, and validation for the detection of lipovitellin in crustacea.	much effort has been put into developing vitellogenin antibodies against a wide variety of aquatic vertebrate species to study potential estrogen or anti-estrogen endocrine disrupters. little work has been done on endocrine disruption in aquatic invertebrates. although some antibodies have been produced against blue crab and penaeid shrimp lipovitellin, they have only poor cross-reactivity with the important estuarine grass shrimp, palaemonetes pugio. vitellin was purified from eggs, monoclonal ...	2000	11083030
methodological and biological aspects to be considered in acetylcholinesterase reactivation assays using 2-pam.	kinetic and toxicological characteristics of fish (odontesthes argentinensis) and crab (callinectes sapidus) cholinesterases as well as methodological conditions to perform reactivation assays using pyridine 2-aldoxime (2-pam) were established. according to kinetic and eserine sensitivity data, both cholinesterases can be considered as acetylcholinesterases. the concentration of eserine that inhibited 50% of enzyme activity (ic(50)) was estimated as 15.9x10(-8) and 4.6x10(-8) m for crab and fish ...	2000	11137467
epizootiology of the parasitic dinoflagellate hematodinium sp. in the american blue crab callinectes sapidus.	hematodinium sp. is a parasitic dinoflagellate that infects and kills blue crabs callinectes sapidus. periodic outbreaks of dinoflagellate infections with subsequent high host mortalities prompted a study of the epizootiology and distribution of the crab pathogen. hemolymph samples from over 13000 crabs were assessed for infections over 8 yr. moderate to high prevalences were found at several locations along the atlantic and gulf coasts of the united states. in the coastal bays of maryland and v ...	2000	11145454
cloning and sequencing of cdnas encoding for a novel copper-specific metallothionein and two cadmium-inducible metallothioneins from the blue crab callinectes sapidus.	metallothioneins (mts) are cysteine-rich metal-binding proteins found in micro-organisms, plants and all invertebrate and vertebrate animals. unicellular eukaryotes such as yeast have a copper-mt whose synthesis is induced by a copper-activated transcription factor. most higher organisms have two major cadmium/zinc mt isoforms, whose synthesis is controlled by a zinc-activated transcription factor. the blue crab, callinectes sapidus, has two cadmium-inducible isoforms, cdmt-i and cdmt-ii, and a ...	2000	11790353
callinectin, an antibacterial peptide from blue crab, callinectes sapidus, hemocytes.	this paper describes the isolation of an approximately 3.7 kda, basic, antibacterial peptide (designated callinectin), which represents the major antibiotic activity in blue crab, callinectes sapidus, hemocytes. a single-step purification using low-pressure cation-exchange chromatology yielded a highly purified (>95%) peptide. purity was confirmed by c4 reverse-phase high-performance liquid chromatography (rp-hplc), native gel electrophoresis, sodium dodecyl sulfate-polyacrylamide gel electropho ...	1999	10373609
a food web analysis of the juvenile blue crab, callinectes sapidus, using stable isotopes in whole animals and individual amino acids.	the stable isotope compositions (c and n) of plants and animals of a marsh dominated by spartina alterniflora in the delaware estuary were determined. the study focused on the juvenile stage of the atlantic blue crab, callinectes sapidus, and the importance of marsh-derived diets in supporting growth during this stage. laboratory growth experiments and field data indicated that early juvenile blue crabs living in the delaware bay habitat fed primarily on zooplankton, while marsh-dwelling crabs, ...	1999	28308018
concurrent signals and behavioral plasticity in blue crab (callinectes sapidus rathbun) courtship.	behavioral flexibility and behavioral regulation through courtship signals may both contribute to mating success. blue crabs (callinectes sapidus) form precopulatory pairs after courtship periods that are influenced by female and perhaps male urine-based chemical signals. in this study, male and female crabs were observed in 1.5-m circular outdoor pools for 45 min while the occurrence and sequence of courtship behaviors and pairing outcomes were recorded. these results were then compared with tr ...	1999	28296500
behavioral physiology of four crab species in low salinity.	reports focusing on the behavioral responses of crabs to exposure to low salinity have involved choice chamber experiments or quantification of changes in activity. in addition to describing changes in locomotor activity in four species of crabs of differing osmoregulatory ability, the present study describes six behaviors: increased movement of the mouthparts, cleaning of the mouthparts with the chelae, cleaning of the antennae and antennules with the maxillipeds, flicking of the antennae, retr ...	1999	28296479
biochemical defense mechanisms against copper-induced oxidative damage in the blue crab, callinectes sapidus.	the blue crab (callinectes sapidus) has a very dynamic copper metabolism associated with the biosynthesis and degradation of its respiratory pigment hemocyanin. in this study we report on the cellular defense mechanisms used by the crab to protect itself from copper toxicity. short-term copper-exposure studies, conducted by incubating hepatopancreas tissue explants in copper-containing medium, show that copper taken up by the cells during the first 60 min combines with low-molecular-weight coppe ...	1998	9514663
female behaviour, sexual competition and mate guarding in the blue crab, callinectes sapidus	blue crabs mate immediately after the female's final moult. we tested the influence of female moult stage, sex ratio and male size on the pre-mating behaviour of both sexes, and the ability of males to pair with females and aggressively compete for access to females. we observed crabs in field enclosures and surveyed pre-copulatory mate-guarding patterns in the field. female behaviour changed as they progressed through the final moult cycle, such that early moult-stage females avoided males, but ...	1998	9514672
molecular cloning of a cdna encoding molt-inhibiting hormone of the crab, cancer magister.	a neuropeptide molt-inhibiting hormone (mih) negatively regulates crustacean molting glands (y-organs). we report here the molecular cloning of a cdna encoding putative mih of the dungeness crab, cancer magister. a cdna library was commercially prepared using poly (a+) rna isolated from c. magister eyestalk neural ganglia. the library was screened using as probe a previously cloned portion of a cdna encoding mih of the blue crab, callinectes sapidus. dna sequence analysis of one positive clone r ...	1998	9548218
molt-inhibiting hormone mrna levels and ecdysteroid titer during a molt cycle of the blue crab, callinectes sapidus.	synthesis of ecdysteroid molting hormones by crustacean y-organs is believed to be regulated by a neuropeptide, molt-inhibiting hormone (mih), produced in eyestalk neural ganglia. in the present study, steady-state mih mrna and hemolymph ecdysteroid levels were determined by northern blot and radioimmunoassay, respectively, during the molt cycle of the blue crab, callinectes sapidus. the level of mih mrna dropped steadily during premolt (d1-d4), reaching a minimum in d3/d4, then increased by 10- ...	1998	9731186
pcr cloning and expression of the molt-inhibiting hormone gene for the crab (charybdis feriatus).	a pcr-based genomic dna walking technique was used to clone the gene for the molt-inhibiting hormone of the crab, charybdis feriatus. several overlapping genomic clones were isolated, and the mih gene for the crab was reconstructed. dna sequence determination of the overlapping clone reveals that the mih gene spans 4.3kb and consists of three exons and two introns. exons 1 and 2 carry a coding sequence for the signal peptide, and exons 2 and 3 consist of coding sequence for the mature peptide. t ...	1998	9931416
perireceptor mechanisms sustaining olfaction at low salinities: insight from the euryhaline blue crab callinectes sapidus	as the blue crab callinectes sapidus moves from sea water to fresh water, the 'exposed' chemosensory dendrites in the olfactory sensilla (aesthetascs) undergo changes in length that are positively correlated with environmental salinity. in this study, we demonstrate the following. (1) the responses of the olfactory receptor cells of freshwater-acclimated crabs are reduced relative to those of seawater-acclimated animals, but increase with a time course comparable to the increase in dendrite leng ...	1997	9318098
the paradigm that all oxygen-respiring eukaryotes have cytosolic cuzn-superoxide dismutase and that mn-superoxide dismutase is localized to the mitochondria does not apply to a large group of marine arthropods.	the enzyme superoxide dismutase (sod), which catalyzes the dismutation of the superoxide radical, is present in the cytosol and mitochondria of all oxygen-respiring eukaryotes. the cytosolic form contains copper and zinc (cuznsod), whereas the mitochondrial form contains manganese (mnsod). the latter protein is synthesized in the cytosol as a mnsod precursor, containing an n-terminal mitochondrial-targeting sequence. cuznsod is sensitive toward cyanide (cn) and hydrogen peroxide (h2o2), but mnso ...	1997	9341231
analysis of metals in blue crabs, callinectes sapidus, from two connecticut estuaries.		1997	8975810
respiratory, acid-base, and metabolic responses of the christmas island blue crab, cardisoma hirtipes (dana), during simulated environmental conditions.	the dependency of the christmas island blue crab, cardisoma hirtipes, on fresh water for respiratory gas exchange and transport was investigated in laboratory simulations. the gas exchange rates of air-breathing c. hirtipes were similar to those of other land crabs but decreased to 20% in submerged crabs. crabs with access to air maintained arterial and pulmonary o2 content (co2) and partial pressure (po2), while in submerged crabs the po2 and co2 rapidly decreased (by 50%). there was no anaerob ...	1997	9231382
synaptic exocytosis of dense-core vesicles in blue crab (callinectes sapidus) stomach muscles.	neuromuscular terminals of a single motoneuron to four muscles (cpv7a, gm5a, cv2, and cv3) in the stomach of the blue crab callinectes sapidus showed structural evidence for the exocytotic release of dense-core vesicles exclusively at synapses. the primary evidence was the appearance of dense cores in the synaptic cleft, accompanied by indentations of the presynaptic or postsynaptic membrane. in their simplest form, these consisted of an omega-shaped figure of the presynaptic membrane enclosing ...	1997	9232830
effects of experience on crab foraging in a mobile and a sedentary species	the effects of experience on prey and prey-patch choice were compared between two species of marine predatory crabs. the blue crab, callinectes sapidus rathbun, is highly mobile and forages in a variety of estuarine and lagoonal habitats. the atlantic mud crab, panopeus herbstii h. milne-edwards, is smaller and less mobile and is found mostly in oyster reefs and on shelly bottoms. in the laboratory, crabs were offered a choice between two prey types (juvenile hard clams, mercenaria mercenaria li ...	1997	9236012
structural-functional differences of a crab motoneuron to four stomach muscles.	a motor unit in the stomach of the blue crab, callinectes sapidus, consists of four separate muscles involved in different aspects of the trituration and filtering of food. motor nerve terminals to two of the muscles (cpv7a and gm5) release small amounts of transmitter (low-output) while those to the other two muscles (cv2 and cv3) release between three and five-fold greater amounts (high-output). structural features underlying the disparity in synaptic strength were analysed with thin serial-se ...	1997	9278868
preliminary assessment of pcb risks to human and ecological health in the lower passaic river.	concentrations of aroclor mixtures and specific polychlorinated biphenyl (pcb) congeners were measured in surface sediments and aquatic biota (striped bass fillet, mummichog, and blue crab muscle and hepatopancreas) collected from the lower passaic river. several of the 47 surface sediment samples contained aroclor concentrations that exceeded a national oceanic and atmospheric administration (noaa) benchmark level for "total pcbs" (22.7 micrograms/kg). each of the 18 pcb congeners analyzed in a ...	1997	9310144
dynamic responses of series force receptors innervating the opener muscle apodeme in the blue crab, callinectes sapidus.	receptors monitoring muscle force innervate the opener muscle apodeme in the walking legs of the blue crab, callinectes sapidus. biocytin backfills reveal 9-15 bipolar neurons with somata as large as 60 micrometer m positioned at the distal end of the apodeme. sensory endings insert into the apodeme and are in series with the opener muscle. the axons of these neurons form the opener apodeme sensory nerve that merges with the most distal branch of the opener motor nerve. recordings reveal that th ...	1997	10866551
phylogeny of the haplosporidia (eukaryota: alveolata) based on small subunit ribosomal rna gene sequence.	the phylogenetic position of the phylum haplosporidia was investigated with the complete small subunit rrna gene sequences from 5 species in the phylum: haplosporidium nelsoni and haplosporidium costale, parasites of the eastern oyster crassostrea virginica; haplosporidium louisiana, a parasite of the mudcrab panopeus herbstii; minchinia teredinis, a parasite of shipworms (teredo spp.) and urosporidium crescens, a hyperparasite found in metacercariae of the trematode megalophallus sp. in the blu ...	1996	8691370
proctolinlike immunoreactivity and identified neurosecretory cells as putative substrates for modulation of courtship display behavior in the blue crab, callinectes sapidus.	pheromonally stimulated courtship display (cd) behavior in male blue crabs (callinectes sapidus) is characterized by rhythmic waving of the fifth legs. the waving of the fifth legs is modulated by proctolin in freely moving crabs and in reduced preparations. to begin to identify an anatomical substrate for cd behavior we have localized putative proctolinergic cells and described the morphology of neurosecretory neurons known to oscillate during pheromonal stimulation of reduced preparations. pro ...	1996	8725299
complete primary structure of the molt-inhibiting hormone (mih) of the mexican crayfish procambarus bouvieri (ortmann).	the amino acid sequence of mih was elucidated by means of digestions with specific proteases, manual edman degradation, and mass spectrometry. mih consists of a 72-residue peptide chain (molecular mass 8322 da) with six cysteines forming three disulfide bridges that connect residues 7-43, 23-39, and 26-52. it has blocked n- and c-termini and lacks tryptophan, histidine, and methionine. mih shows striking similarity to the crustacean hyperglycemic hormone (chh) isomorphs of procambarus bouvieri ( ...	1996	8735961
antimicrobial susceptibility and plasmid-mediated streptomycin resistance of plesiomonas shigelloides isolated from blue crab.	five plesiomonas shigelloides strains isolated from retail or wild-catch louisiana blue crabs (callinectes sapidus) were examined for resistance to selected antibiotics and presence of plasmids. three agar media, macconkey, salmonella-shigella and a modification of inositol brilliant green bile salt (ibb), were evaluated for isolation of p. shigelloides. of these, ibb was most satisfactory for distinguishing between p. shigelloides and the related species aeromonas hydrophila. isolates were susc ...	1996	8760329
distribution of dopamine-like immunoreactivity suggests a role for dopamine in the courtship display behavior of the blue crab, callinectes sapidus.	injection of dopamine initiates a posture in the blue crab, callinectes sapidus, identical to courtship display behavior of the male crab. the threshold for proctolin-induced rhythmic components of courtship display is lowered in preparations when dopamine is co-applied with proctolin. to elucidate the anatomical substrate of this behavior, immunocytochemistry was used to map dopamine-immunoreactive neurons. courtship display is sex-specific, and dependent on the hormonal, developmental, and sea ...	1996	8766168
risk of clostridium botulinum type e toxin production in blue crab meat packaged in four commercial-type containers.	the aim of this investigation was to determine if a risk of clostridium botulinum growth and toxin production existed in four different packaged crabmeat products. freshly picked blue crab meat was inoculated with 10(3) to 10(4) spores per g of a mixed pool of four strains of c. botulinum type e (beluga, minnesota, g21-5, and 070). the lump crabmeat was packaged in four different packaging containers: (i) 12-oz copolymer polyethylene cups currently used by most crab processors; (ii) 12-oz copoly ...	1996	10463443
quality characteristics of fresh blue crab meat held at 0 and 4 degrees c in tamper-evident containers.	there has been a regulatory movement toward the required use of tamper-evident containers for fresh blue crab meat. north carolina passed tamper-evident regulations in 1993. blue crab processors had little information on possible changes in head-space gases, microbial growth, chemical decomposition, sensory quality, or shelf life caused by the new containers. chemical, microbiological, physical, and sensory changes in fresh crab meat were monitored during 18 days of storage in ice and 13 days of ...	1996	10463450
chlordane contamination in selected estuarine and coastal marine finfish and shellfish of new jersey, usa.	analysis of chlordane contamination in selected finfish and shellfish species from estuarine and coastal marine waters of new jersey, usa, indicates consistently highest organochlorine pesticide levels in samples from the north and northeast regions of the state. gas chromatographic analysis of tissue samples from four finfish species (american eel, anguilla rostrata; bluefish, pomatomus saltatrix; striped bass, morone saxatilis; and weakfish, cynoscion regalis) and one shellfish species (blue c ...	1996	15093520
atrial natriuretic peptide gene expression within invertebrate hearts.	the present investigation was designed to (1) determine if atrial natriuretic factor gene expression occurs within invertebrates as well as within vertebrates; (2) determine whether the product of this gene expression is the 126-amino-acid atrial natriuretic factor prohormone or some other molecular species; and (3) evaluate within the same invertebrates if the products of atrial natriuretic factor gene expression are released into their circulation. utilizing a very sensitive rnase protection a ...	1995	8575660
a comparison of the gill physiology of two euryhaline crab species, callinectes sapidus and callinectes similis: energy production, transport-related enzymes and osmoregulation as a function of acclimation salinity	callinectes sapidus and c. similis co-occur in estuarine waters above 15 salinity. callinectes sapidus also inhabits more dilute waters, but c. similis is rarely found below 15 . previous work suggests that c. sapidus may be a better hyperosmoregulator than c. similis. in this study, energy metabolism and the levels of transport-related enzymes in excised gills were used as indicators of adaptation to low salinity. oxygen consumption rates and mitochondrial cytochrome content of excised gills in ...	1995	9317943
a comparison of calcium binding in callinectes sapidus premolt and postmolt cuticle homogenates: implications for regulation of biomineralization.	cuticle tissue homogenates (cths) from callinectes sapidus premolt cuticle bound approximately 367% more ca2+ ions than did those from the postmolt cuticle. the ph-stat assay which was used to compare in vitro caco3 nucleation times confirmed that the premolt cths had greater inhibitory activity than did the postmolt cths. this inhibitory activity was indicated by caco3 nucleation times in excess of control values. premolt nucleation times exceeded those of postmolt samples by approximately 340% ...	1995	8747426
primary structure and tissue-specific expression of blue crab (callinectes sapidus) metallothionein isoforms.	in aquatic animals, synthesis of the metal-binding protein metallothionein (mt) can be induced through exposure to elevated levels of metals in food or water. whether the different routes of exposure lead to expression of different metallothionein isoforms in different tissues in unknown. in this study we examined the induction of metallothionein isoforms in the hepatopancreas and gills of the blue crab callinectes sapidus. when blue crabs are exposed to cadmium in their diet, the metal accumula ...	1995	7487904
molecular cloning of a cdna encoding putative molt-inhibiting hormone from the blue crab, callinectes sapidus.	a cdna library was constructed using poly(a+) rna isolated from eyestalk neural ganglia of the blue crab, callinectes sapidus. the library was screened using a probe generated by pcr based on the published amino acid sequence of molt-inhibiting hormone from the shore crab, carcinus maenas. dna sequence analysis of one positive clone revealed a 339 bp open reading frame encoding a 78-residue putative molt-inhibiting hormone and a 35-residue signal peptide. the deduced amino acid sequence of c. sa ...	1995	7537497
a highly conserved red pigment-concentrating hormone precursor in the blue crab callinectes sapidus.	a cdna library was established from the eyestalk ganglia of the blue crab callinectes sapidus. one clone was isolated (644 bp excluding the poly(a) tail) which encodes the red pigment-concentrating hormone (rpch)-precursor, consisting of the 25 amino acid residue signal peptide, the rpch, and a 73 amino acid residue rpch-precursor related peptide. this clone displays high sequence similarity with a clone isolated from an eyestalk cdna library of the shore crab carcinus maenas, in accordance with ...	1995	7611999
coordination and neuromuscular control of rhythmic behaviors in the blue crab, callinectes sapidus.	the stereotypical courtship display (cd) behavior of the male blue crab, callinectes sapidus, includes an unusual component: the rhythmic waving of the swimming appendages above the carapace. this behavior occurs in a unique context but it resembles two other rhythmic behaviors performed using the swimming legs: sideways swimming and backward swimming. as a first step to understanding the mechanisms that allow the expression of apparently different rhythmic motor patterns, we have examined these ...	1995	7643320
modulation of behavior by biogenic amines and peptides in the blue crab, callinectes sapidus.	using the blue crab callinectes sapidus as a model system, we have investigated the effects of potential neuromodulators on freely behaving animals. of interest is the modulatory effect of a number of drugs on three rhythmic behaviors of the blue crab: courtship display (cd) of the male crab, sideways swimming and backward swimming. the drugs tested were proctolin, dopamine, octopamine, serotonin, and norepinephrine. injection of each drug elicited a unique posture or combination of limb movemen ...	1995	7643321
neuromodulation of rhythmic motor patterns in the blue crab callinectes sapidus by amines and the peptide proctolin.	the blue crab callinectes sapidus, provides an opportunity to study neuromodulation of three variations of rhythmic behavior produced by the same appendages. these behaviors are sideways swimming, backward swimming and courtship display (cd). each behavior has a different context, and despite similarities among them, each is quantifiably distinguishable. cd behavior occurs in males, is stimulated naturally by pheromone, and elements of the behavior are evoked by proctolin and dopamine. sideways ...	1995	7643322
three-dimensional solution structure of callinectes sapidus metallothionein-1 determined by homonuclear and heteronuclear magnetic resonance spectroscopy.	metallothionein is a cysteine-rich metal-binding protein whose biosynthesis is closely regulated by the level of exposure of an organism to zinc, copper, cadmium, and other metal salts. the metallothionein from callinectes sapidus is known to bind six divalent metal ions in two separate metal-binding clusters. heteronuclear 1h-113cd and homonuclear 1h-1h nmr correlation experiments have been used to establish that the two clusters reside in two distinct protein domains. the three-dimensional sol ...	1995	7819257
distribution and characterization of angiotensin-converting enzyme-like activity in tissues of the blue crab callinectes sapidus.	angiotensin-converting enzyme-like activity (acela) was determined in tissue homogenates of the blue crab, callinectes sapidus, using the synthetic substrate hippuryl-histidyl-leucine (hip-his-leu) and the specific inhibitor, captopril. acela was highest in gill homogenates followed by the hepatopancreas and hemolymph with specific activities of 1.69, 0.37 and 0.10 nmol/min/mg protein, respectively. gill enzyme activity was membrane-associated and no difference in activity was noted between ante ...	1994	7915656
evaluation of lactic acid bacterium fermentation products and food-grade chemicals to control listeria monocytogenes in blue crab (callinectes sapidus) meat.	fresh blue crab (callinectes sapidus) meat was obtained from retail markets in florida and sampled for viable listeria monocytogenes. the pathogen was found in crabmeat in three of four different lots tested by enrichment and at levels of 75 cfu/g in one of the same four lots by direct plating. next, crabmeat was steam sterilized, inoculated with a three-strain mixture of l. monocytogenes (ca. 5.5 log10 cfu/g), washed with various lactic acid bacterium fermentation products (2,000 to 20,000 arbi ...	1994	7944362
subunit composition of hemocyanins of callinectes sapidus: phenotypes from naturally hypoxic waters and isolated oligomers.	the electrophoretic banding pattern of hemocyanin monomers in blue crabs caught in natural waters indicate that the phenotypes associated with normoxia or hypoxia in the laboratory can also be found in those conditions in nature. page of pure fractions of 1 x 6-mers isolated by hplc revealed only the two invariant plus one slightly variable band. in contrast, the 2 x 6-mer fraction contained those three plus the three highly variable bands. these results support the hypothesis formulated by earl ...	1994	7953073
molecular cloning of two pigment-dispersing hormone (pdh) precursors in the blue crab callinectes sapidus reveals a novel member of the pdh neuropeptide family.	a cdna library was established from the eyestalk ganglia of the blue crab callinectes sapidus. screening resulted in the isolation of a clone (497 bp excluding poly(a) tail) which encodes a beta-pdh previously found in several crustacean species. it displays high sequence similarity with a clone isolated from an eyestalk cdna library of the shore crab carcinus maenas, indicating the close phylogenetic relationship of both species. a second clone (414 bp exclusive of the poly(a) tail) encodes a n ...	1994	7999056
hemolymph lectins of the blue crab, callinectes sapidus, recognize selected serotypes of its pathogen vibrio parahaemolyticus.		1994	8192339
enterotoxigenic escherichia coli and staphylococcus aureus in fish and seafood from the southern region of brazil.	an investigation to evaluate the microbiological condition and safety of fish and seafood commonly harvested at the coast of santa catarina state and sold in florianópolis was undertaken. one hundred and seventy-five samples of fish and fish fillets (cynoscion leiarchus), shrimp tails (peneaus paulensis), shellfish-meat (anomalocardia brasiliensis and metilus edulis), and crab-meat (callinectes sapidus) were collected from markets and examined within 4 h of purchase. for isolation and enumeratio ...	1994	7703011
effect of the external concentration of calcium on the postmoult uptake of calcium in blue crabs (callinectes sapidus)	the rate of calcium uptake in blue crabs (callinectes sapidus rathbun) acclimated to 2 sea water with a calcium concentration of 1.4 mmol l-1 was dependent on the magnitude and direction of the electrochemical gradient for calcium. when transferred to water with a high calcium concentration (6 mmol l-1), the electrochemical gradient for calcium favoured diffusive influx, and calcium uptake and apparent h+ excretion increased by approximately 50 %. when transferred to water with a low calcium con ...	1994	9317209
mechanism of the net uptake of water in moulting blue crabs (callinectes sapidus) acclimated to high and low salinities	blue crabs (callinectes sapidus rathbun) acclimated to a salinity of 2 approximately doubled in wet mass (excluding carapace) during the period from 10 h before moult to 2 h after moult. both in blue crabs acclimated to 2 salinity and in crabs acclimated to 28 salinity, the drinking rate increased from approximately 0.4 ml 100 g-1 h-1 at 1 day prior to moult to approximately 8 ml 100 g-1 h-1 during the first hour after moult. the drinking rate had decreased 1 day after moult in both salinities, ...	1994	9317238
post-exercise lactate production and metabolism in three species of aquatic and terrestrial decapod crustaceans	aquatic and terrestrial crustaceans are dependent on both aerobic and anaerobic metabolism for energy production during exercise. anaerobic energy production is marked by an accumulation of lactate in both muscle tissue and haemolymph, but the metabolic fate of lactate is not clear. lactate recycling via gluconeogenesis and the potential role of carbonic anhydrase (ca) in supplying bicarbonate for the carboxylation of pyruvate were investigated in three species of decapod crustaceans: callinecte ...	1994	9317667
crab: snail size-structured interactions and salt marsh predation gradients.	we studied size-structured predator-prey interactions between blue crabs (callinectes sapidus) and marsh periwinkles (littoraria irrorata) with a combination of field studies, laboratory experiments and individual-based modeling. size distributions of littoraria differed among years at the same sites in a salt marsh and could largely be explained by dominance of strong cohorts in the population. at a given site, abundance increased with elevation above tidal datum. size-selective predation by bl ...	1994	28313589
trace elements and organochlorines in the shoalgrass community of the lower laguna madre, texas.	our objectives were to measure concentrations of seven trace elements and 14 organochlorine compounds in sediment and biota of the shoalgrass (halodule wrightii) community of the lower laguna madre of south texas and to determine whether chemicals associated with agriculture (e.g. mercury, arsenic, selenium, organochlorine pesticides) were highest near agricultural drainages. arsenic, mercury, selenium, lead, cadmium, and organochlorines were generally at background concentrations throughout the ...	1993	24225804
coarse woody debris as a refuge from predation in aquatic communities : an experimental test.	this study demonstrates experimentally that coarse woody debris (cwd) can provide refuge from predation in aquatic habitats. in the rhode river subestuary of chesapeake bay, maryland, (usa), we (1) measured the abundance of cwd, (2) examined the utilization of cwd by mobile epibenthic fish and crustaceans, and (3) tested experimentally the value of cwd as a refuge from predation. cwd was the dominant above-bottom physical structure in shallow water, ranging in size from small branches (<2 cm dia ...	1993	28313814
a putative glutathione-binding site in cdzn-metallothionein identified by equilibrium binding and molecular-modelling studies.	glutathione (gsh) has been found to form a complex with both vertebrate and invertebrate copper-metallothionein (cumt) [freedman, ciriolo and peisach (1989) j. biol. chem. 264, 5598-5605; brouwer and brouwer-hoexum (1991) arch. biochem. biophys. 290, 207-213]. in this paper we report on the interaction of gsh with cdznmt-i and cdznmt-ii from rabbit liver and with cdmt-i from blue crab hepatopancreas. ultrafiltration experiments showed that all three mts combined with gsh. the measured binding da ...	1993	8363576
depolarization-activated potentiation of the t fiber synapse in the blue crab.	the blue crab t fiber synapse, associated with the stretch receptor of the swimming leg, has a nonspiking presynaptic element that mediates tonic transmission. this synapse was isolated and a voltage clamp circuit was used to control the membrane potential at the release sites. the dependence of transmitter release on extracellular calcium, [ca]o, was studied over a range of 2.5-40 mm. a power relationship of 2.7 was obtained between excitatory postsynaptic potential (epsp) rate of rise and [ca] ...	1993	8382259
hemocyanin synthesis in the blue crab callinectes sapidus.	1. the synthesis of hemocyanin in the blue crab, callinectes sapidus, was investigated by molecular techniques. 2. polyadenylated mrna was prepared from the hepatopancreas and translated in rabbit reticulocyte lysate. 3. translation products were immunoprecipitated with immobilized antihemocyanin igg. analysis of the igg-bound polypeptides by sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed two polypeptides comigrating with authentic callinectes hemocyanin. 4. a synthetic degener ...	1993	8448995
isolation of antho-rfamide related peptides from the eyestalks of blue crab.	1. two carboxyl-terminally amidated peptides (cp1 and cp2) were isolated from the blue crab (callinectes sapidus) eyestalks by a method of carboxyl-terminal analysis. 2. the peptides were sequenced as pglu-gly-arg-phe-amide (cp1) and pglu-leu-gly-arg-phe-amide (cp2). 3. each carboxyl-terminus of the peptides was precisely determined by amino acid analysis utilizing phenylisothiocyanate derivatives. 4. cp1 was identical to the sea anemone neuropeptide, antho-rfamide.	1993	8462277
induction of metallothionein mrna in the blue crab (callinectes sapidus) after treatment with cadmium.	1. dietary treatment of blue crabs with cadmium led to an increase of cadmium metallothionein in the hepatopancreas. 2. utilizing a unique purification procedure, poly a+ rna was isolated from the hepatopancreas of control and cadmium-treated blue crabs with 260/280 nm ratios of 2.0 or better. 3. poly a+ rna was hybridized with a series of oligonucleotide probes derived from a portion of the amino acid sequence of lobster metallothionein. a single band of approx. 300 base pairs was present in co ...	1993	8098685
shell disease and metal content of blue crabs, callinectes sapidus, from the albemarle-pamlico estuarine system, north carolina.	concentrations of 13 elements were determined for three tissues (gill, hepatopancreas, muscle) in diseased crabs from a contaminated estuary (pamlico river, nc), and in non-diseased crabs from both the contaminated estuary and a relatively uncontaminated area (albemarle sound, nc) during the fall 1989 and summer 1990. the diseased crabs had lesions which completely penetrated their dorsal integument, while the non-diseased crabs lacked lesions. sediments within the contaminated area showed enric ...	1992	1456781
novel protein inhibits in vitro precipitation of calcium carbonate.	organic molecules both coexist and interact with inorganic crystal lattices in biomineralizing tissues. mineral precipitation and crystal morphology are tightly regulated by the actions of these molecules. polyacrylamide gel electrophoresis studies on water soluble extracts from the cuticle of callinectes sapidus (atlantic blue crab) reveal the presence, in unmineralized nascent premolt cuticle, of proteins which are absent in the mineralized postmolt cuticle. in the present studies, homogenates ...	1992	1497356