Influence de la température sur quelques activités enzymatiques chez Palaemon serratus

Variation in Esterase 2 C activities, involving the hydrolysis of 2-carboxylic esters, α-glucosidase acetyl-glucosaminidase and alkaline and acid phosphotases, in the hepatopancreas and the abdominal muscle of Palaemon serratus was examined by polyacrylamide gradient gel electrophoresis. Soluble proteins were measured in the hepatopancreas and the abdominal muscle, and trypsin and chymotrypsin activities in the hepatopancreas. The activities and the isoenzymatic variations in shrimps acclimated at 5 different temperatures (between 14 and 30°) were compared and the molecular weight of each isozyme evaluated. It was found that: (a) the concentrations of soluble proteins decrease in the hepatopancreas between 18 and 30°, but remain unchanged in the abdominal muscle; (b) esterase and phosphatase activities increase with temperature but in a more or less random manner, according to the isozyme under consideration; (c) glycosidase activities increase with temperature; and (d) trypsin activity varies in an inverse relation to chymotrypsin activity.     

Influence de l'intensité lumineuse sur quelques activités enzymatiques chez Palaemon serratus

Esterase 2 C activities, involving the hydrolysis of 2-carbon carboxylic esters, α-glucosidase, acetylglucosaminidase, alkaline and acid phosphatases in the hepatopancreas of Palaemon serratus, were examined by polyacrylamide gradient gel electrophoresis. The isoenzymatic equipments of shrimps acclimated at 6 different ligh intensities (1 to 1200 lx) were compared. Enzymatic activities were measured and the molecular weight of each isozyme was evaluated. It was found that (a) the concentration of soluble proteins decreases between 1 and 600 lx; (b) esterase 2 C and alkaline phosphatase activities increase substantially between 1 and 1200 lx; (c) for these two activities, light intensity acts differently according to the isozyme under consideration; (d) α-glucosidase activities vary inversely with acetylglucosaminidase activity at light intensities greater than 150 lux.     

Studies on lactate dehydrogenase activity in the shrimp Palaemon serratus

The influence of seasonal variations in the temperature of the environment on the kinetic parameters of LDH have been followed in the shrimp Palaemon serratus. The results obtained show that this system compensates partially the effects of the temperature on its activity. The complex pattern of the monthly variations of Km values along the year can be resolved into a 2 plateaux system corresponding to the extreme temperature of the environment.     

A redescription of Periclimenaeus fimbriatus Borradaile, 1915, with the designation of a new genus (Crustacea: Decapoda: Palaemonidae)

Specimens of Periclimenaeus fimbriatus Borradaile, 1915, a palaemonid shrimp reported from only three localities in the Western Indian Ocean, are described and illustrated. The species is removed from the genus Periclimenaeus Borradaile and a new genus Paraclimenaeus is designated for its accommodation. The characteristic features of the genus and its relationships are discussed. The palaemonid shrimp genera associated with sponge hosts are reviewed and a key provided for their identification     

Microsatellite loci in the eastern form of the giant freshwater prawn (Macrobrachium rosenbergii)

Six microsatellite loci were identified and characterized in the eastern form of the widespread and commercially important giant freshwater prawn (Macrobrachium rosenbergii). The loci were detected by randomly screening for dinucleotide and trinucleotide repeat units within a partial genomic library developed for the species. In a sample of 29 prawns, number of alleles and heterozygosity per locus ranged from 12 to 18 and from 0.66 to 0.90, respectively. These markers provide powerful tools for the conservation and management of wild stocks, the improvement of cultured stocks of M. rosenbergii, and for investigating evolutionary processes underlying genetic divergence among populations.     

九香虫血淋巴及其纯化蛋白抑菌活性的研究

对九香虫AsporgopuschinensisDallas血淋巴及其血淋巴蛋白质分离物的抗菌活性进行了研究,抗菌活性检测指示菌为大肠杆菌Escherichiacoli和金黄色葡萄球菌Staphilocalliesacereus。测定结果表明,九香虫血淋巴及其离心上清液都具有明显的抗菌活性。用凝胶过滤法从血淋巴蛋白分离提纯获得一种小分子肽,SDS PAGE电泳为单一带,分子量约为1～1 4 4kD。该小分子蛋白对大肠杆菌和金黄色葡萄球菌都有抑菌作用,与血淋巴对2种细菌的抗菌性一致,表明其是九香虫血淋巴中具抗菌作用的主要物质之一。     

九香虫血淋巴对肿瘤细胞凋亡相关蛋白表达的影响

探索九香虫血淋巴诱导肿瘤细胞凋亡的作用通路。利用Bradford法检测九香虫血淋巴浓度并将其作用于体外培养的人乳腺癌MCF-7细胞、人胃癌SGC-7901细胞,Western blot法检测经九香虫血淋巴干预后肿瘤细胞凋亡相关蛋白Caspase-3、Caspase-8、Caspase-9、Bcl-2、Bax等的表达。结果显示,九香虫血淋巴作用的SGC-7901、MCF-7细胞中Caspase-3、Caspase-9、Bax蛋白的表达较对照组细胞明显上调;两种细胞的Bcl-2蛋白,较对照组细胞表达明显下调;两种细胞的Caspase-8蛋白,较对照组细胞表达无明显差异。结果表明,经九香虫血淋巴诱导的SGC-7901、MCF-7细胞可能通过触发其线粒体凋亡途径使肿瘤细胞发生不可逆的凋亡。     

Bacteria-induced haemolymph proteins of Manduca sexta pupae and larvae

The haemolymph of Manduca sexta larvae and pupae has been analyzed for proteins potentially associated with the bacterial defence response of the insect. Five proteins, M13, M18, M20, M23, and M24 in pupae, and M4, M11, M13, M18 and M23 in larvae, are induced by the injection of bacteria into the haemolymph. Proteins M4 and M11 are always present at high levels in uninjected pupae. Proteins M20 and M24 could not be induced in larvae. These proteins, as well as those not showing a response to bacterial challenge or injury, were also analyzed for presence of disulphide bonds and carbohydrate moieties, and their apparent molecular weights determined.     

Eclosion hormone activity in haemolymph of eclosing silkmoth, Bombyx mori

The presence of eclosion hormone in the haemolymph of eclosing adults of the silkworm, Bombyx mori, was demonstrated to provide evidence that the hormone is involved in the induction of eclosion of this insect.The eclosion of the adult occurred within 55–75 min after light-on, when the pupae had been kept under conditions of 16 h light and 8 h dark during adult development. The hormone became detectable in the haemolymph 10–20 min after light-on, followed by eclosion 40 min later. The hormonal activity increased sharply to a maximal level (30 units/ml haemolymph) at 30 min prior to the eclosion and then fell rapidly: detectable eclosion hormone was present in the haemolymph for only 15–20 min. The hormone was partially purified from the haemolymph of eclosing animals and a 400-fold purification was achieved. The preparation was rather stable against heat treatment, and the molecular weight was estimated to be 5,000–10,000 by gel-filtration on a Sephadex G-50 (superfine). The origin of eclosion hormone in the haemolymph is discussed.     

Acides aminés de microsporidies parasites de crustacés décapodes marins

The amino acids of four species of Microsporidia parasitizing crustaceans were investigated: three species — Thelohania maenadis, Ormieresia carcini and Ameson pulvis — are parasites of Carcinus mediterraneus; Inodosporus sp. is a parasite of Palaemon serratus. Seventeen protein amino acids were identified of which aspartic acid, glutamic acid and lysine were quantitatively the most important, being quantitatively similar in all four parasites. The relative amounts of the next most abundant amino acids were found to vary and might serve as a systematic criterion at the genus level. For example, phenylalanine is predominant in Ormieresia and leucine in Inodosporus: serine in Thelohania and glycine in Ameson are also predominant, but to a lesser extent. The free amino acids composition shows little qualitative variation among the four genera, but quantitative differences are found in the composition of Microsporidia parasitizing the same host species; this may reflect variations in the amino acid metabolism of the parasite. The urea cycle in Ormeresia is most remarkable in this connection. The free amino acid level in the parasites was generally found to be in inverse proportion to the level in the host; the amino acids which are found to exist at high levels in the parasites correspond to essential amino acids of the Crustacea. Metabolic and adaptative relations are discussed.     

Crustacea Decapoda of the Paripe River Estuary, Pernambuco, Brazil

The Paripe river estuary is located in Itamaracá Island, north coast of Pernambuco, northeastern Brazil. Its Crustacea Decapoda fauna was studied during several years. In the estuary there are mangroves, mud- and sandbanks, and tidal creeks. The fauna comprises a total of 64 species in 20 families. The coexistence of these species confirms the ecological importance of this small estuary, only 1.6 km long and 0.5 km wide. The ecology of each species in the estuary is presented.     

Behavioral and morphological aspects of decorating in Oregonia gracilis (Brachyura: Majoidea)

Abstract. Decorator crabs (Brachyura: Majoidea) are known for attaching sessile organisms to specialized velcro-like hooked setae. Here we describe behavioral and morphological aspects of decorating for a common northern Pacific majoid, Oregonia gracilis . Members of O. gracilis decorate with a diverse array of sessile organisms. These are attached to hooked setae, and also physically interact with long, pappose setae that occur in the same body regions as hooked setae. We describe these pappose setae and document the occurrence of similar setae in 36 other decorating majoids across seven families. In O. gracilis , the density of pappose and hooked setae independently covary with decoration amount, which is sexually dimorphic—juveniles and adult females decorate heavily, whereas adult males decorate sparsely. Adult males have reduced numbers of hooked and pappose setae, but the ontogenetic patterns for the two setal types are different, suggesting that they are quasi-independent characters. We experimentally ablated pappose setae to ask if they functionally contribute to decorating in O. gracilis . Surprisingly, we found that pappose setae are not necessary for decorating under laboratory conditions. Pappose setae could play an auxiliary mechanical role or a sensory role in decorating, or may have another as-yet-unidentified function distinct from decorating.     

Larval development of the subantarctic king crabs<Emphasis Type="Italic"> Lithodes santolla</Emphasis> and<Emphasis Type="Italic"> Paralomis granulosa</Emphasis> reared in the laboratory

The larval development and survival in the two subantarctic lithodid crabs Lithodes santolla (Jaquinot) and Paralomis granulosa (Molina) from the Argentine Beagle Channel were studied in laboratory cultures. In L. santolla, larval development lasted about 70 days, passing through three zoeal stages and the megalopa stage, with a duration of approximately 4, 7, 11 and 48 days, respectively. The larval development in P. granulosa is more abbreviated, comprising only two zoeal stages and the megalopa stage, with 6, 11 and 43 days' duration, respectively. In both species, we tested for effects of presence versus absence of food (Artemia nauplii) on larval development duration and survival rate. In P. granulosa, we also studied effects of different rearing conditions, such as individual versus mass cultures, as well as aerated versus unaerated cultures. No differences in larval development duration and survival were observed between animals subjected to those different rearing conditions. The lack of response to the presence or absence of potential food confirms, in both species, a complete lecithotrophic mode of larval development. Since lithodid crabs are of high economic importance in the artisanal fishery in the southernmost parts of South America, the knowledge of optimal rearing conditions for lithodid larvae is essential for future attempts at repopulating the collapsing natural stocks off Tierra del Fuego.Communicated by H.-D. Franke     

Effects of haemolymph free cations on blowfly taste receptor responses

Ionic composition of the haemolymph and electrophysiological responses of tarsal taste hairs were determined for individual flies of the species Calliphora vicina, in order to test the hypothesis that electrophysiological response values of individual flies are correlated with the ionic composition. Instead of flame photometry we used isotachophoresis to determine the ionic composition; only non-bound ions contribute to the result. Because of this we found lower concentration values than those reported so far. There was a strong correlation between the concentrations of the cations Na⁺, K⁺ and Mg²⁺, while Ca²⁺ was not related with any other cation. A significant correlation was shown to exist between the response of taste cells and the Na⁺, K⁺ and Ca²⁺ content in the haemolymph. These correlations explain, at least partly, the systematic differences in taste cell responses between flies, as reflected in interindividual variability.     

Circadian rhythms of melatonin in haemolymph and optic lobes of Chinese mitten crab (Eriocheir sinensis) and Chinese grass shrimp (Palaemonetes sinensis)

This study is the first to examine the circadian rhythms of melatonin in Eriocheir sinensis and Palaemonetes sinensis, two economically important crustaceans. We collected haemolymph and optic lobes from both species every 4 h over a whole day cycle. Melatonin content was measured with high-performance liquid chromatography. E. sinensis haemolymph exhibited significant (p < 0.05) peaks in melatonin at 16:00 (0.180 ± 0.020 μg·mL^?1) and 24:00 (0.244 ± 0.055 μg·mL^?1), while eyestalks had significant peaks at 16:00 (72.377 ± 18.100 μg·eyestalk^?1) and 24:00 (98.756 ± 30.271 μg·eyestalk^?1). In P. sinensis, melatonin peaked significantly only at 16:00 in optic lobes (12.493 ± 1.475 μg·eyestalk^?1) (p < 0.05); no significant peaks were present in haemolymph. Thus, both E. sinensis and P. sinensis exhibit species-specific melatonin rhythms. Time of day should therefore be considered when examining the physiological status of both crustaceans, given the potential influence of fluctuating daily melatonin concentrations.     

棉铃虫不同虫态及虫龄血淋巴中酚氧化酶活力的比较

分别测定了棉铃虫Helicoverpa armigeraHübner不同虫态及虫龄血清和血细胞中酚氧化酶(phenoloxidase,PO)的活力。结果显示血清和血细胞中都有酚氧化酶活性,且血细胞中高于血清中。不同虫态及虫龄的血清和血细胞中酚氧化酶活力有很大的不同,血清和血细胞中酚氧化酶活力变化规律一致。3龄幼虫酶活力最高,5龄幼虫最低。酶活力大小依次为:3龄幼虫>预蛹>4龄幼虫>蛹>5龄幼虫     

Circadian variation in the free fatty acid level of abdominal muscle of Palaemon serratus (Pennant 1777) Crustacea, Decapoda]

Free fatty acids extracted from the abdominal muscle of Palaemon serratus (Crustacea, Decapoda) maintained on a L-D: 19-5 photoperiod show important circadian variations, characterised by two diurnal maximums and one nocturnal by the end of dark period. Principal maximum is diurnal and occurs 7 hours after the beginning of the light phase.     

Freeze-tolerance adaptations,including haemolymph protein and lipoprotein nucleators,in the larvae of the cranefly Tipula trivittata

The terrestrial overwintering larvae of the cranefly Tipula trivittata were freeze tolerant (able to survive the freezing of their extracellular body fluids) throughout the winter and spring of 1982–1983 until they pupated in mid-May. The larvae were most cold tolerant (24 h lower lethal temperatures of ?25 to ?30°C) in late January and early February. Sorbitol, at a maximal concentration of ～0.4 M, was the only polyol determined to be present at high levels and sorbitol accounted for most of the seasonal fluctuation in osmotic concentration. Haemolymph inorganic ion (Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl^?) concentrations did not vary seasonally.The supercooling points of the larvae remained constant at ?6 to ?7°C over the study period because of the presence of haemolymph ice nucleating factors. These ice nucleating factors consist not only of haemolymph proteins, as had been demonstrated previously in other insect species, but also lipoproteins.     

Possible involvement of an enzymatic system for superoxide generation in lepidopteran larval haemolymph

The superoxide generative system in Pseudaletia separata larval haemolymph plasma was shown to consist of at least two components, low (LMF) and high (HMF) molecular weight factors using ultrafiltration, dialysis, and gel filtration. The LMF was concluded to be a molecule(s) smaller than 5 kDa while the HMF to be a protein(s) larger than 100 kDa. The total amount of superoxide produced depended on the amount of LMF and was independent of that of HMF added to the reaction mixture. Both the LMF and HMF were required for O₂^? generation. From results in the present article, it was hypothesized that the LMF was a substrate(s) discharging electrons and HMF was an enzyme(s) to mediate the electron transfer to O₂ forming O₂^?. Superoxide production was detected in the haemolymph plasma of 5 lepidopteran species in addition to P. separata. It was concluded that superoxide production is a common phenomenon at least in these lepidopterans. © 1995 Wiley-Liss, Inc.