| the hemolymph proteins of the blue crab, callinectes sapidus. ii. a lipoprotein serologically identical to oocyte lipovitellin. | | 1969 | 4978665 |
| ultrastructural study of microsporidian development. i. nosema sp. sprague, 1965 in callinectes sapidus rathbun. | | 1970 | 4986525 |
| [comparative study of the ultrastructure of androgenic glands from normal and eyestalkless crabs during larval life or after puberty in the species: rhithropanopeus harrisii (gould) and callinectes sapidus rathbun]. | | 1971 | 5157128 |
| sterols, fatty acids and sterol content in eggs and hepatopancreas of the blue crab callinectes sapidus (rathbun). | | 1969 | 5372851 |
| biological relationship of callinectes sapidus (rathbun) with carcinonemerteans, bryozoan, and barnacles. | | 1970 | 5412351 |
| electrical properties of axons of callinectes sapidus. | | 1970 | 5459481 |
| ultrastructural study of the neurosecretory granules in the sinus gland of the blue crab, callinectes sapidus. | | 1971 | 5543303 |
| steroidogenesis in the blue crab callinectes sapidus rathbun. | | 1971 | 5559128 |
| conversion of progesterone to 11-deoxycorticosterone by the androgenic gland of the blue crab (callinectes sapidus rathbun). | | 1969 | 5765442 |
| volume control by muscle fibers of the blue crab. volume readjustment in hypotonic salines. | single isolated muscle fibers from the walking legs of the blue crab, callinectes sapidus act as boyle-van't hoff osmometers with an osmotically inactive volume of 33 %. fibers in hypotonic salines undergo a spontaneous volume readjustment toward the initial volumes of the cells found in isotonic salines. the volume readjustment is initiated by the increase in cell volume in hypotonic salines and appears to be dependent on the duration of exposure of the fiber to external sodium, the sodium conc ... | 1969 | 5767335 |
| vibrio parahaemolyticus from the blue crab callinectes sapidus in chesapeake bay. | strains of vibrio parahaemolyticus, the etiologic agent of "shirasu" food poisoning in japan, were isolated from moribund blue crabs callinectes sapidus and identified by biochemical and serological techniques. | 1969 | 5770620 |
| the hemolymph proteins of the blue crab, callinectes sapidus. i. hemocyanins and certain other major protein constituents. | | 1969 | 5788602 |
| a disease of blue crabs (callinectes sapidus) in maryland and virginia. | | 1966 | 5939400 |
| ultrastructural studies of sperm morphology and sperm-egg interaction in the decapod callinectes sapidus. | | 1966 | 5948806 |
| free amino acids in developing stages of two crabs, callinectes sapidus rathbun and rhithropanopeus harrisii (gould). | | 1966 | 6013506 |
| the glucuronic acid pathway in the blue crab, callinectes sapidus rathbun: the enzymes of the udpglucose to glucuronic acid portion of the pathway. | | 1967 | 6035559 |
| effect of single and continuous exposures of gamma radiation on the survival and growth of the blue crab, callinectes sapidus. | | 1967 | 6066585 |
| shell disease of the blue crab, callinectes sapidus. | | 1967 | 6070691 |
| calcium and the tonic release of transmitter at a non-impulsive synapse in the crab. | depolarization-transmitter release coupling was studied in the promotor stretch receptor/motoneuron synapse of the crab. callinectes sapidus, a preparation in which presynaptic action potentials do not occur. intracellular microelectrode recordings were made from the presynaptic terminal and from the somata of postsynaptic motoneurons while injecting current pulses into the peripheral stretch receptor dendrite with the aid of the sucrose-gap. 1. for short current pulses, the relationship between ... | 1980 | 6109020 |
| salinity adaptation of hco3--dependent atpase activity in the gills of blue crab (callinectes sapidus). | a bicarbonate-dependent atpase (ec 3.6.1.3) was found in microsomal preparations from blue crab gills. when the crabs were transferred to low salinity (200 mosmolal) from seawater (1000 mosmolal), the hco3- dependent atpase increased in all gill pairs, reaching its new steady state in 2 weeks. the greatest increase occurred in the sixth and seventh gill pairs (approx. 2.5-fold). maximal enzyme activity was observed at an mg2+ concentration of 2 mm and an optimal ph of 7.8. the apparent ka for hc ... | 1982 | 6125214 |
| microsomal cytochromes p-450 from marine crabs. | cytochromes p-450 were isolated from the hepatopancreas of several species of crabs (libinia emarginata, callinectes sapidus, menippe mercenaria and uca minax). elution profiles from an ion exchange column showed similar profiles for all species, indicating one broad cytochrome p-450 peak eluting at 0.2 m k cl. hydroxyapatite chromatography resolved the p-450 into three forms (cytochromes p-450i, p-450ii and p-450iii). the forms of cytochrome p-450 in the different crabs were compared with respe ... | 1984 | 6149863 |
| uptake and survival of enteric viruses in the blue crab, callinectes sapidus. | uptake of poliovirus 1 by the blue crab, callinectes sapidus, was measured to assess the likelihood of contamination by human enteric viruses. virus was found in all parts of the crab within 2 h after the crab was placed in contaminated artificial seawater. the highest concentrations of virus were found in the hemolymph and digestive tract, but the meat also contained virus. the concentration of virus in the crabs was generally less than in the surrounding water. changes in salinity did not subs ... | 1981 | 6261683 |
| concentration of rotavirus and enteroviruses from blue crabs (callinectes sapidus). | a simple method for concentration and detection of rotavirus and enteroviruses in the blue crab is described. virus was separated from tissue homogenates at ph 9.5, concentrated by adsorption to protein precipitates at ph 3.5, and recovered by elution of precipitates at ph 9.2. test samples of 12 to 15 ml were produced from an initial 100 g of crab tissues. cat-floc precipitation was used to remove sample toxicity for cell cultures. recovery effectiveness averaged 52% with poliovirus 1, echoviru ... | 1983 | 6318667 |
| trace metal residues in shellfish from maryland waters, 1976-1980. | levels of seven heavy metal residues, arsenic, cadmium, chromium, copper, lead, mercury and zinc were monitored in samples of the american oyster (crassostrea virginica), the soft shell clam (mya arenaria), the hard shell clam (mercinaria mercinaria) and the blue crab (callinectes sapidus). samples were taken from the maryland section of the chesapeake bay and its tributaries over a five year period (1976-80). this study was undertaken to provide an estimate of a baseline for values of trace hea ... | 1984 | 6501792 |
| organochlorine residues in shellfish from maryland waters, 1976-1980. | shellfish samples, including the american oyster (craessostrea virginica), the soft shell clam (mya arenaria), the hard shell clam (mercenaria mercenaria) and the blue crab (callinectes sapidus), were taken from the maryland section of the chesapeake bay and its tributaries over a five year period (1976-80) and analyzed to determine residue levels of various organochlorine pesticides. qualitative and quantitative information was obtained for a variety of polychlorinated hydrocarbons. the purpose ... | 1984 | 6501793 |
| acid-base regulation during exercise and recovery in the blue crab, callinectes sapidus. | during swimming activity callinectes sapidus incurred a severe hemolymph acidosis due to elevated levels of pco2 and lactate. although hemolymph lactate concentration rose steadily during 1 h of exercise, hemolymph ph was maximally depressed within the first 15 min. a discrepancy between the quantities of lactate and h+ released from the tissues into the hemolymph is explained by a large apparent efflux of h+ into the ambient seawater, presumably via a branchial ion exchange process. ammonia exc ... | 1984 | 6528111 |
| metal ion interactions with limulus polyphemus and callinectes sapidus hemocyanins: stoichiometry and structural and functional consequences of calcium(ii), cadmium(ii), zinc(ii), and mercury(ii) binding. | hemocyanins are oligomeric metalloproteins containing binuclear copper centers that reversibly combine with oxygen molecules. the structural stability and functional properties of these proteins are modified by divalent cations. equilibrium dialysis was used to study the reversible interaction of callinectes sapidus and limulus polyphemus hemocyanins with the divalent cations calcium, cadmium, zinc, copper, and mercury. the number of binding sites and association constants for each cation were o ... | 1983 | 6626526 |
| recognition of xenogeneic proteins by the blue crab: dissociation of the clearance and degradation reactions and lack of involvement of circulating hemocytes and humoral factors. | blue crabs clear foreign proteins from the circulation to the gills in a manner that can be explained by postulating the participation of a finite number of naturally occurring quasi-specific receptors. the rate of this clearance reaction is not increased by previous exposure to the foreign protein although recovery to the normal rate of clearance after high level blockade is quite rapid. the cleared foreign proteins are degraded in the gills in a relatively nonspecific fashion suggestive of a c ... | 1984 | 6724091 |
| total lipid and cholesterol content in the blue crab, callinectes sapidus rathbun. | total lipid and cholesterol concentrations in hepatopancreas, gonad and muscle were analyzed for 70 blue crabs. the concentrations were highest in hepatopancreas, then gonad, and muscle was the lowest. in male crabs, the concentrations decreased from the immature stage (feeding and growth stage) to the mature stage (breeding stage), and from august to september (breeding period) in mature males. in female crabs, the concentrations were comparatively high for peelers (pre-molting stage) and matur ... | 1984 | 6744830 |
| the intracellular partitioning of trace metals in marine shellfish. | marine organisms have evolved a number of metabolic strategies to deal with potentially toxic trace metals. to determine how "detoxification" mechanisms such as metal-binding proteins and concretions are involved in the intracellular partitioning of trace metals in marine shellfish, the oyster, crassostrea virginica, and the blue crab, callincetes sapidus, were exposed to controlled levels of trace metals. oysters accumulated cadmium readily and produced specific low molecular weight, cadmium-bi ... | 1983 | 6879150 |
| specificity for tail fibers of a humoral crab factor neutralizing t2 bacteriophage. | it is now becoming clear that invertebrates, animals lacking the ability to make humoral antibodies, are capable of recognizing self from non-self. in several instances this recognition is manifest in normal ("unimmunized") animals by a rapid clearance of certain foreign materials from the circulation one example of such a rapid innate reaction involves the clearance of t2 bacteriophage from the blue crab (1). other studies have indicated that blue crab plasma contained a factor capable of neutr ... | 1982 | 7067888 |
| heavy metal ion interactions with callinectes sapidus hemocyanin: structural and functional changes induced by a variety of heavy metal ions. | hemocyanins are oligomeric proteins that reversibly bind oxygen. the oxygen binding site is a binuclear copper center bound to the protein by amino acid side chains. the hemocyanin of the blue crab, callinectes sapidus, occurs in vivo as a mixture of 25s dodecamers and 16s hexamers, whose oxygen binding properties are identical. four heavy metals have been used as probes of structure and function in this hemocyanin system. divalent cations of cadmium, copper, mercury, and zinc induced an indefin ... | 1982 | 7093201 |
| incidence of vibrio species associated with blue crabs (callinectes sapidus) collected from galveston bay, texas. | bacteria were readily isolated from the hemolymph of a majority (88%) of the blue crabs collected from galveston bay, texas. the hemolymph of most crabs contained moderate (greater than 10(3) bacteria/ml) to heavy (greater than (10(5) bacteria/ml) infections. large variances were observed in the bacterial number associated with individual crabs, but no significant difference was observed between the mean bacterial levels in the hemolymph of crabs collected during different seasons of the samplin ... | 1982 | 7103475 |
| cadmium-binding proteins from blue crabs (callinectes sapidus) environmentally exposed to cadmium. | | 1982 | 7106072 |
| diurnal changes in compound eye fine structure in the blue crab callinectes. 1. differences between noon and midnight retinas on an ld 11:13 cycle. | | 1982 | 7200529 |
| subunit structure and dissociation of callinectes sapidus hemocyanin. | the hemocyanin of the blue crab, callinectes sapidus has two major components sedimenting with approximate sedimentation coefficients of 17 s and 25 s. molecular weight data based on light scattering and sedimentation equilibrium measurements at ph 7.8 suggest that the two components have molecular weights of approximately 450 000 and 900 000 in the presence of stabilizing ca2+. in the absence of ca2+, the molecular weights are found to be about 5% lower, suggesting some dissociation of the hemo ... | 1981 | 7213799 |
| toxicity of ozonated estuarine water to juvenile blue crabs (callinectes sapidus) and juvenile atlantic menhaden (brevoortia tyrannus). | | 1981 | 7248539 |
| effect of the amino acid histidine on the uptake of cadmium from the digestive system of the blue crab, callinectes sapidus. | | 1981 | 7296034 |
| amiloride-sensitive ammonium and sodium ion transport in the blue crab. | in the estuarine crab, callinectes sapidus, net nh4+ efflux was twice as high in animals acclimated to 17% salinity seawater (sw) (0.495 +/- 0.084 mumol . h-1 . g wet wt-1, n = 7) than in animals acclimated to full-strength 35% sw (0.212 +/- 0.028 mumol . h-1 . g-1, n = 7). amiloride (3 x 10(-4) m) in the external sw reversibly inhibited these effluxes by 63 +/- 6% (n = 6) and 67 +/- 6% (n = 5), respectively. unidirectional na+ influx was reversibly inhibited 42 +/- 6% (n = 7) by amiloride in 17 ... | 1981 | 7304782 |
| 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 |
| 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 |
| 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 |
| 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 |
| hemolymph lectins of the blue crab, callinectes sapidus, recognize selected serotypes of its pathogen vibrio parahaemolyticus. | | 1994 | 8192339 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |