Lagenidium Callinectes Research Articles

Design and synthesis of marine natural product-based 1H-indole-2,3-dione scaffold as a new antifouling/antibacterial agent against fouling bacteria

Marine organisms such as seaweeds, sponges and corals protect their own surfaces from fouling by their high anesthetic, repellant, and settlement inhibition properties. Within the marine ecosystem, evolution has allowed for the development of certain antifouling properties. Isatin is a biologically active chemical produced by an Alteromonas sp. strain inhibiting the surface of embryos of the cardiean shrimp Palaemon macrodectylus, which protect them from the pathogenic fungus Lagenidium callinectes. In present study, an antibacterial activity of isatin and its synthetic analogues were evaluated against different fouling bacteria in order to explore the structure activity relationships for the first time. The synthesized compounds along with parent isatin were tested against different ecologically relevant marine microorganisms by using the Kirby–Bauer disc diffusion method. Few synthetically modified isatin exhibited potent inhibitory activity at concentration of 2μg/disc against Planococcus donghaensis, Erythrobacter litoralis, Alivibrio salmonicida, Vibrio furnisii. Overall, the modified analogues showed stronger activity than the parent marine natural product (isatin) and hence 1H-indole-2,3-dione scaffold has immense potential as future antibacterial/antifouling candidate.

Lagenidium callinectes INFECTION ON ROTIFERS Brachionus sp.

Milkfish, Chanos chanos and humpback grouper, Cromileptes altivelis hatcheries have developed at Gondol, Bali since 1995 and until now still rely on rotifers, the main natural food, supply. Recent problem on mass culture of rotifer, Brachionus sp. is harvest failure caused by fungus infection. Under light microscope, infected eggs and bodies of the rotifers was filled with numerous aseptate hyphae. Two isolates of fungi were isolated from rotifer eggs and carcass on June 21st, 2004 and on June 25th, 2004 obtained from milkfish and humpback grouper hatcheries at Gondol. Based on its morphological characteristics, the pathogenic fungus was identified as Lagenidium callinectes which grows optimally at 25°C and survives in 1.0%, 2.5%, and 5.0% NaCl as well as in 1.0% and 2.5% KCl. Both of the present isolates utilize only 8 out of 26 carbohydrates and derivatives tested as carbon, nutrition and energy sources. This finding is the first report on rotifer, Brachionus sp. infected with L. callinectes causing up to 100% mortality.

Identification of lower fungi isolated from larvae of mangrove crab, Scylla serrate, in Indonesia

Since 1992, seed production of mangrove crab,Scylla serrata, has been attempted at the Gondol Research Station for Coastal Fisheries, Bali, Indonesia. During the production process, almost all of the larvae have died due to fungal infection. Fungi isolated from the larvae with fungal infection were classified into three species in the order Lagenidiales:Lagenidium callinectes, Haliphthoros milfordensis andHalocrusticida baliensis sp. nov. based on detailed morphological characteristics. The effects of temperature, pH and mineral content of the water on their growth were also examined.

Pathogenicity of fungi isolated from the larvae of the mangrove crab, Scylla serrata, in Indonesia

Heavy mortality reaching almost 100% occurred in the larvae of the mangrove crab,Scylla serrata, from July to December 1997 at the hatchery of Gondol Research Station for Coastal Fisheries in Bali, Indonesia. Mortality was observed in larvae after hatching from the eggs. The affected larvae were whitish and filled with numerous aseptate hyphae. Three fungi belonging to the order Lagenidiales,Lagenidium callinectes, Haliphthoros milfordensis, andHalocrusticida sp., were isolated from the infected larvae. Pathogenicity tests of the infected fungi against the larvae of mangrove crab demonstrated that all isolates were pathogenic.

Lagenidium callinectes (Couch, 1942) infection and its control in cultured larval Indian tiger prawn, Penaeus monodon Fabricius

AbstractA mycosis in larval tiger prawn, Penaeus monodon Fabricius, is described for the first time from India. The hyphae of Lagenidium callinectes are contorted, irregularly branched, sparingly septate, and contain a cell wall and membrane, vacuoles, mito chondria, ribosomes, small and large vesicles, and Woronin bodies. The spores occur singly or in pairs. The fungal mycelium may either invade and embed itself in the tissues, or alternatively, replace all the muscle tissues of the infected larval P. monodon. Fungus infected, untreated populations of nauplii, zoea and myksis exhibited mortalities of 5.33 ± 0.55%, 24.68 ± 4.58% and 47.89 ± 0.27%, respectively. A 0.5 ppm treatment with trifluralin significantly reduced the mortality of infected larval populations (i.e. 1.1% nauplii, 3.28% zoea and 5.21% myksis mortality). Lagenidium sp. exhibited growth in potato dextrose agar medium and in Sabouraud's agar at 28 °C.

Three species of Lagenidiales isolated from the eggs and zoeae of the marine crab Portunus pelagicus

Three species of Lagenidiales were isolated from the eggs and zoeae of the marine crabPortunus pelagicus. One of them,Lagenidium callinectes, is reported for the first time in Japan, with fungal infection in the eggs.Haliphthoros milfordensis was discovered from a zoea of the crab.Atkinsiella okinawaensis was also isolated from a zoea of the crab and described as a new species. Growth temperature range and optimum temperature of the fungi were examined. All of the isolates grew at various concentrations of NaCl or KCl, and optimum growth was observed on PYGS agar containing seawater. Pathogenicity to zoeae of the swimming crabPortunus trituberculatus was demonstrated by using a zoospore suspension of each fungus at 25°C.

Presqualene metabolism in two species of Lagenidium.

The fate of precursors of the isoprenoid pathway was studied in the sterol auxotroph Lagenidium giganteum and in the positive control organism Lagenidium callinectes. Acetate derived from glucose and mevalonic acid was converted to sterols and fatty acids in L. callinectes. Lagenidium giganteum converted mevalonic acid to sterols and fatty acids, but glucose-derived acetate was not utilized for sterol synthesis. The results showed that the defect in the isoprenoid pathway of L. giganteum occurs at the level of the beta-hydroxy-beta-methylglutarylcoenzyme A reductase-synthase complex. Various aspects of this defect are discussed relative to metabolism of the organism.

Squalene metabolism in two species of Lagenidium.

Squalene metabolism of the sterol auxotroph Lagenidium giganteum was studied and compared with that of the positive control Lagenidium callinectes. Application of experimentally derived precautions ensured both the stability and the purity of squalene during incubations. Under these conditions mycelia of L. giganteum converted squalene to squalene oxide and to a sterol-like compound. Cell-free and microsomal preparations also converted squalene to the oxide, which was identified by thin layer chromatography with five different solvent systems, by co-chromatography with authentic oxide, and by conversion to the glycol. Supporting evidence for the production of squalene oxide was obtained by gas-liquid chromatography, high performance liquid chromatography, and autoradiography. The squalene oxide produced was identified by mass spectrometry.

Embryos of Homarus americanus are Protected by Epibiotic Bacteria.

Embryos of the American lobster, Homarus americanus, are remarkably resistant to infection by the fungus Lagenidium callinectes, a pathogen of many crustaceans. The surfaces of healthy lobster embryos are covered almost exclusively by a single, Gram-negative bacterium, which grows in a dense mosaic pattern. In culture, this bacterium produces a compound that completely inhibits the growth of the pathogenic fungus in vitro at 10 mcg/ml. Large-scale fermentation, extraction, and subsequent chromatographic purification led to the identification of the antifungal substance as 4-hydroxyphenethyl alcohol (tyrosol), an antibiotic substance known to be produced by terrestrial fungi.

Hyphal Wall Chemistry of Lagenidium callinectes and Lagenidium chthamalophilum

The chemical composition of mechanically isolated hyphal walls of the marine fungi Lagenidium callinectes and Lagenidium chthamalophilum was determined using biochemical, cytochemical, and x-ray diffraction analysis. In both fungi, the primary wall constituents were β-glucans, containing predominately (1→3)- and (1→6)-linked glucosyl residues; glucan accounted for 79% of wall dry weight in L. callinectes and 66% of wall dry weight in L. chthamalophilum. Cellulose was demonstrated by cytochemical and x-ray diffraction analysis and accounted for 7.8% and 7.5% of wall dry weight in L. callinectes and L. chthamalophilum, respectively. Additionally, hyphal walls contained mannose, protein, ash (inorganic), and lipid. Respectively, these constituents were found to account for 0.7%, 5.4%, 3.5%, and 5.8% of wall dry wreight in L. callinectes and 2.7%, 9.8%, 2.9% of wall dry weight in L. chthamalophilum (...)

Potential use of ozone to disinfect sea water of fungi causing diseases of cultured marine crustacea

This report describes the testing of ozone as a treatment of water for the removal of spores of fungi ( Lagenidium callinectes, Haliphthoros milfordensis, and Fusarium solani) having known, severe pathogenicity to cultured marine crustacea. Using a specially designed test apparatus and dry weight analysis of fungal growth at timed intervals, ozone (measured on the basis of total residual oxidant TRO) effected 100% mortality of the test organisms at approximately 6–9 min after initiation of ozone introduction to the system, at a final TRO concentration of approximately 0.8–1.0 ppm. Microscopic examination indicated that death of the spores was due to cellular lysis resulting in total cytoplasmic disruption. Results from the present study are compared with similar tests involving fungi, bacteria, protozoa, and viruses.

Symbiotic marine bacteria chemically defend crustacean embryos from a pathogenic fungus.

Embryos of the shrimp Palaemon macrodactylus are remarkably resistant to infection by the fungus Lagenidium callinectes, a recognized pathogen of many crustaceans. An Alteromonas sp. bacterial strain consistently isolated from the surface of the embryos, produces 2,3-indolinedione (isatin), a compound that inhibits the pathogenic fungus. If exposed to the fungus, bacteria-free embryos quickly die, whereas similar embryos reinoculated with the bacteria or treated only with 2,3-indolinedione live well. The commensal Alteromonas sp. bacteria protect shrimp embryos from fungal infection by producing and liberating the antifungal metabolite 2,3-indolinedione.

AnIn VitroAnalysis of Egg Mortality inCancer anthonyi: The Role of Symbionts and Temperature

Several symbionts occur on crab eggs. These symbionts, and the effect of temperature, have been implicated as causal mechanisms of egg mortality in Cancermagister. The contribution of three symbionts (a fungus, Lagenidium callinectes; bacteria, i.e., Leucothrix sp.; and a nemertean worm, Carcinonemertes epialti) to egg mortality on Cancer anthonyi were investigated in vitro using a multifactorial experimental design at four different temperatures. The nemertean worm was found to contribute most to egg mortality on the individual crab and at the crab population level because its prevalence was high (>95%) and it had a relatively constant feeding rate. Lagenidium callinectes caused from 20-75% egg mortality on individual crabs but its prevalence was nil. A Lagenidium-like fungus had a low prevalence (2.6%) and was not associated with egg mortality. While bacteria were omnipresent, they were found to cause negligible crab egg mortality. Few significant interactions were observed between the symbionts. Temperature had a significant effect on worm feeding rates, worm oviposition, and fungal attack rates. At low temperatures (4 and 10°C), symbionts killed fewer eggs than at higher temperatures (15 and 20°C). Extreme temperatures (4 and 20°C) caused variable degrees of egg mortality, yet some eggs survived at these temperatures. Temperature also had a profound effect on egg development. At 20°C, eggs developed almost twice as fast as those at 10°C. Development appeared to stop at 4°C.

A novel lipoprotein from Oomycete fungi

This work reports on the presence of an endogenous lipoprotein in Lagenidium giganteum and Phytophthora cinnamomi as well as from the related non-sterol-deficient Oomycete species Lagenidium callinectes, and Zoophagus insidians. The lipoproteins comprise 0.2-1.0% of the total cell protein and are easily extracted with 0.2% Tween-80. The lipoprotein is homogeneous following heparin-agarose chromatography and nondenaturing gel electrophoresis. This holoprotein from all species had a molecular mass of 320,000 Da and contained four identical protein subunits of molecular mass 40,600. The lipoprotein exhibited similar physical characteristics to human low-density lipoprotein (LDL) as it comigrated with LDL on agarose gels, coeluted with LDL from heparin-agarose columns, and had a similar buoyant density of 1.006-1.063 g/cm 3. The associated lipids varied quantitatively by species and included dolichol, diglycerides, and phospholipids. The lipoproteins from sterol-deficient species bound exogenous cholesterol without displacement of any of the native lipids of the lipoprotein.

Phylogenetic implications of sterol biosynthesis in the oomycetes

The effects of two fungicides, triarimol and tridemorph, on sterol biosynthesis were examined in Achlya americana, Dictyuchus monosporous, Apodachlyella completa, and Lagenidium callinectes. Cultures grown in the presence of triarimol accumulated lanosterol, with the exception of Lagenidium which had inconclusive results. All tridemorph-treated cultures accumulated Δ 8-sterols, including zymosterol, fecosterol, and stigmasta-8, E-24(28)-dienol. Results point to the intermediacy of lanosterol but not cycloartenol in sterol biosynthesis in the Oomycetes. These data suggest that the evolution of the Oomycetes from photosynthetic algal ancestors is unkikely.

A comparison of cycloartenol and lanosterol biosynthesis and metabolism by the Oomycetes

Representative members in each of the four orders of Oomycetes (Phytophthora cactorum, Peronosporales;Lagenidium callinectes, L. giganteum, Lagenidiales;Saprolegnia ferax, Saprolegniales;Apodachylella completa, Leptomitales) have been examined for their ability to synthesize and polycyclize squalene-oxide (SO) to a tetracyclic product and to differentiate between cycloartenol and lanosterol metabolism to sterols.P. cactorum andL. giganteum failed to synthesize or metabolize SO, cycloartenol or lanosterol. While the other three fungi synthesized sterols via SO and lanosterol, a minor metabolism of added cycloartenol to the 4,4-desmethyl-14α-methylcyclosteroid dehydropollinastanol was observed.

EGGS OFPALAEMON MACRODACTYLUS:III. INFECTION BY THE FUNGUS,LAGENIDIUM CALLINECTES

Eggs of the estuarine shrimp, Palaemon macrodactylus, were studied under various conditions to determine their susceptibility to a known fungal pathogen, Lagenidium callinectes. Eggs exhibited no signs of fungal infection under normal conditions, but were infected when detached from the female or when the female's first pereiopods (cleaning chelipeds) were excised. This implied that preening or egg removal by the first pereiopods halted infection or obviated detection of the fungus. Nutrient addition increased the number of infections and decreased the time to infection. Fertilized eggs were less susceptible to infection than unfertilized, probably the result of the hardened fertilization membrane restricting fungal penetration. Similarly, older embryos with progressively hardened coats were also less susceptible. Defense may have also been provided by antifungal bacteria isolated from embryo surfaces. Two of these epizooic bacteria belong to the marine genus, Alteromonas, and release extracellular enzy...

Ultrastructural changes induced in zoospores of Lagenidium callinectes by exposure to Captan

The effects of the fungicide Captan on growth, development, and fine structure of the marine fungus Lagenidium callinectes Couch are studied. At the minimum lethal concentration (LC100) of Captan for L. callinectes (3.2 ppm active component), zoospores exposed for 30 min failed to encyst or germinate. Ultrastructural changes caused by exposure to Captan included "washing-out" of the mitochondrial matrix and disappearance of many of the cristae, clumping of the chromatin and disappearance of the nuclear matrix, and swelling of the cisternae of the endoplasmic reticulum. Longer exposure of zoospores to Captan resulted ultimately in breakdown of the plasma membrane. These observations were in agreement with those of previous studies which indicated that the toxic action of Captan occurs primarily in mitochondria.

Occurrence and Distribution in North Carolina Waters of Lagenidium callinectes Couch, a Fungal Parasite of Blue Crab Ova

Ovigerous blue crabs,Callinectes sapidus, collected from certain North Carolina waters during the periods June, 1, 1971, to August 1, 1971, and May 1, 1972, to August 1 1972, were examined for infection of the ova with the fungus,Lagenidium callinectes. During the period May 1, 1972, to August 1, 1972, the rate of infection was as high as 95% during the month of May, but declined steadily during June and July with no infected crabs being collected after July 19, 1972. Attempts to correlate infection rate with water temperature and salinity were inconclusive. Other crabs that had ova that were naturally infected withL. callinectes includedPanopeus herbstii andLibinia dubia. Ova ofMenippe mercenaria were susceptible to artificial infection in the laboratory.

The Morphology of Lagenidium Callinectes II. Zoosporogenesis

Zoosporogenesis in the holocarpic marine phycomycete Lagenidium callinectes is initiated when actively growing mycelium is washed free of medium and placed in sea water. Portions of hyphae are wall...