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1.
The association between the red macroalga Jania adhaerens J. V. Lamour. and the sponge Haliclona caerulea is the most successful life‐form between 2 and 4 m depth in Mazatlán Bay (Mexican Pacific). J. adhaerens colonizes the rocky intertidal area and penetrates into deeper areas only when it lives in association with H. caerulea. The aposymbiotic form of the sponge has not been reported in the bay. To understand the ecological success of this association, we examined the capacity of J. adhaerens to acclimate in Mazatlán Bay using transplant experiments. The transplanted aposymbiotic J. adhaerens did not survive the first 2 weeks; however, J. adhaerens when living in association with H. caerulea, acclimated easily to depth, showing no sign of mortality during the 103 d of the experiment. We conclude that the ability of J. adhaerens to colonize in deeper areas in this hydrodynamic environment may in part rely on the protection provided by the sponge to the algal canopy. Both species contribute to the shape of the associated form. Nevertheless, the morphological variation in the association appears to be dominated by the variation in J. adhaerens canopy to regulate pigment self‐shading under light‐limited conditions and/or tissue resistance under high hydrodynamics. Consequently, our results are consistent with light as the abiotic controlling factor, which regulates the lower depth distribution of the association in Mazatlán Bay, through limiting the growth rate of J. adhaerens. Hydrodynamics may determine the upper limit of the association by imposing high mass losses. 相似文献
2.
Evariquinone,isoemericellin, and stromemycin from a sponge derived strain of the fungus Emericella variecolor 总被引:2,自引:0,他引:2
From a strain of the fungus Emericella variecolor derived from the marine sponge Haliclona valliculata, two new natural products, evariquinone and isoemericellin, were isolated after HPLC-UV, -MS, and -NMR studies of the extract and their structures were elucidated by mass spectrometry and NMR experiments. Evariquinone showed antiproliferative activity towards KB and NCI-H460 cells at a concentration of 3.16 microg/ml. Furthermore, the fungus was found to produce the known metabolites stromemycin, shamixanthone, and 7-hydroxyemodin. Chemical degradation, NMR decoupling experiments, and spin-system simulation provided evidence for the double bonds in stromemycin to be all E-configured. ROESY experiments established the monosaccharide moiety to be glucose. 相似文献
3.
P.W. Baker J. Kennedy J. Morrissey F. O’Gara A.D.W. Dobson J.R. Marchesi 《Journal of applied microbiology》2010,108(5):1668-1675
Aims: The conversion of cheap cellulosic biomass to more easily fermentable sugars requires the use of costly cellulases. We have isolated a series of marine sponge‐derived fungi and screened these for cellulolytic activity to determine the potential of this unique environmental niche as a source of novel cellulase activities. Methods and Results: Fungi were isolated from the marine sponge Haliclona simulans. Phylogenetic analysis of these and other fungi previously isolated from H. simulans showed fungi from three phyla with very few duplicate species. Cellulase activities were determined using plate‐based assays using different media and sea water concentrations while extracellular cellulase activities were determined using 3,5‐dinitrosalicylic acid (DNSA)‐based assays. Total and specific cellulase activities were determined using a range of incubation temperatures and compared to those for the cellulase overproducing mutant Hypocrea jecorina QM9414. Several of the strains assayed produced total or relative endoglucanase activities that were higher than H. jecorina, particularly at lower reaction temperatures. Conclusions: Marine sponges harbour diverse fungal species and these fungi are a good source of endoglucanase activities. Analysis of the extracellular endoglucanase activities revealed that some of the marine‐derived fungi produced high endoglucanase activities that were especially active at lower temperatures. Significance and Impact of the Study: Marine‐derived fungi associated with coastal marine sponges are a novel source of highly active endoglucanases with significant activity at low temperatures and could be a source of novel cellulase activities. 相似文献
4.
Sponge secondary metabolites have been investigated to find potential lead compounds for the development of commercially interesting products. During the Camellia project entitled Environmentally compatible antifouling coatings for the protection of ships, water systems, fish cages and other immersed structures against aquatic growth, several analogues of terpenes containing isocyano, thioisocyano, thiocyano and formamide functionalities were synthesized and evaluated for their antifouling activity against the settlement of the barnacle Balanus amphitrite. The best activities were obtained with N-formylated alkylamines the length of the carbon chain of which is comprised between C-11 and C-14. In the aromatic series, the isocyano derivatives showed high antifouling activities. But they were too toxic against many microorganisms to be incorporated in paint formulations. During the Symbiosponge project entitled Biology of sponge natural products the methanolic extract of about 230 sponges were submitted to bioassays guided fractionation to isolate bioactive compounds. Several cytostatic sesquiterpene quinones and tryptamine-derived alkaloids were isolated from 4 sponges of the genus Hyrtios. A new 4-sphingenine analogue and a novel polyacetylenic derivative were found to be responsible for the bioactivities of the methanolic extracts of Haliclona vansoesti and Callyspongia pseudoreticulata, respectively. 相似文献
5.
Four new polyhydroxylated sterols, named halicrasterols A–D (1–4), together with six known analogs (5–10) were isolated from the marine sponge Haliclona crassiloba. Compounds 1 and 2 represented rare examples of steroids featuring 17(20)E-double bonds. The structures of 1–10 were elucidated by spectroscopic analysis and comparison with reported data. This is the first report of a steroid profile for this species. The antimicrobial activities of 1–10 were evaluated against a panel of bacterial and fungal strains in vitro, and compounds 4 and 9 showed moderate activity against some of the Gram-positive strains with MICs ranging from 4 to 32 μg/mL. 相似文献
6.
In vitro sponge cultures are considered as legitimate alternatives for utilizing marine sponges (Porifera) to yield bioactive
molecules. Optimization of culture methodologies for enhancing sponge survival is in progress for the identification of the
factors regulating sponge survival in vitro. Dissolved oxygen (DO) is an essential factor promoting sponge survival. However,
the effects of variable DO levels on the in vitro survival responses of sponges are not fully understood. Hence, we have investigated
the effects of variable DO levels on the survival of the marine sponge, Haliclona pigmentifera (Demospongiae), with no external nutritional supplementation in closed type incubator chambers. Our results indicate that,
under hypoxic conditions (1.5-2.0 ppm DO), H. pigmentifera with intact ectodermal layers and subtle oscula show adherent growth for 42±3 days. Sponges with prominent oscula, foreign
material, and damaged pinacoderm exhibit poor survival under similar conditions. Complete mortality occurs within 2 days under
anoxia (<0.3 ppm DO), and survival for a few days has been observed at >4.0 ppm DO without adhesion. Cellular differences
between the outer and inner zones and collagen-like extracellular matrix have been identified in adherent sponges. Based on
the hypothesis that hypoxia-inducible factor1-α (HIF-1α) is a ubiquitous protein promoting hypoxic survival in animals, we
have detected, by Western blot, a protein band corresponding to human HIF-1α-like protein from sponges exposed to hypoxia
and to hypoxia-mimicking agents. We thus report, for the first time, adhesive growth and a protein band corresponding to human
HIF-1α-like protein in sponges surviving hypoxia in vitro.
This work was supported by the “Task Force Network Programme (CMM-004)” of the Council of Scientific and Industrial Research
(CSIR), Government of India and by the Department of Ocean Development. CSIR is also acknowledged for providing a Senior Research
Fellowship to V.G.G. 相似文献
7.
8.
Grant AJ Trautman DA Menz I Hinde R 《Biochemical and biophysical research communications》2006,348(1):92-98
Two distinct cell signals have been isolated from the sponge host of the tropical sponge/macroalga symbiotic association Haliclona cymiformis/Ceratodictyon spongiosum. These water soluble cell signals (M(r) between 500 and 1000) modify separate steps in the carbon metabolism in both C. spongiosum and the microalga, Symbiodinium from the coral Plesiastrea versipora. The first signal, host release factor (HRF), stimulates the release of compounds derived from algal photosynthesis; the second signal, photosynthesis inhibiting factor (PIF), partially inhibits photosynthesis. Both HRF from the sponge H. cymiformis and HRF from the coral P. versipora stimulated the release of glycerol from Symbiodinium suggesting that they act at a similar step in the metabolism of this alga. This is the first time that such cell signals have been isolated from a sponge. We suggest that they belong to a family of similar cell signals from symbiotic invertebrates that modify algal carbon metabolism. 相似文献
9.
Phelan RW O'Halloran JA Kennedy J Morrissey JP Dobson AD O'Gara F Barbosa TM 《Journal of applied microbiology》2012,112(1):65-78
Aims: Despite the frequent isolation of endospore‐formers from marine sponges, little is known about the diversity and characterization of individual isolates. The main aims of this study were to isolate and characterize the spore‐forming bacteria from the marine sponge Haliclona simulans and to examine their potential as a source for bioactive compounds. Methods and Results: A bank of presumptive aerobic spore‐forming bacteria was isolated from the marine sponge H. simulans. These represented c. 1% of the total culturable bacterial population. A subgroup of thirty isolates was characterized using morphological, phenotypical and phylogenetic analysis. A large diversity of endospore‐forming bacteria was present, with the thirty isolates being distributed through a variety of Bacillus and Paenibacillus species. These included ubiquitous species, such as B. subtilis, B. pumilus, B. licheniformis and B. cereus group, as well as species that are typically associated with marine habitats, such as B. aquimaris, B. algicola and B. hwajinpoensis. Two strains carried the aiiA gene that encodes a lactonase known to be able to disrupt quorum‐sensing mechanisms, and various isolates demonstrated protease activity and antimicrobial activity against different pathogenic indicator strains, including Clostridium perfringens, Bacillus cereus and Listeria monocytogenes. Conclusions: The marine sponge H. simulans harbours a diverse collection of endospore‐forming bacteria, which produce proteases and antibiotics. This diversity appears to be overlooked by culture‐dependent and culture‐independent methods that do not specifically target sporeformers. Significance and Impact of Study: Marine sponges are an as yet largely untapped and poorly understood source of endospore‐forming bacterial diversity with potential biotechnological, biopharmaceutical and probiotic applications. These results also indicate the importance of combining different methodologies for the comprehensive characterization of complex microbial populations such as those found in marine sponges. 相似文献
10.
The interest in sponges has increased rapidly since the discovery of potential new pharmaceutical compounds produced by many sponges. A good method to produce these compounds by using aquaculture of sponges is not yet available, because there is insufficient knowledge about the nutritional needs of sponges. To gain more insight in the nutritional needs for growth, we studied the growth rate of Haliclona oculata in its natural environment and monitored environmental parameters in parallel. A stereo photogrammetry approach was used for measuring growth rates. Stereo pictures were taken and used to measure volumetric changes monthly during 1 year. Volumetric growth rate of Haliclona oculata showed a seasonal trend with the highest average specific growth rate measured in May: 0.012 +/- 0.004 day(-1). In our study a strong positive correlation (p < 0.01) was found for growth rate with temperature, algal biomass (measured as chlorophyll a), and carbon and nitrogen content in suspended particulate matter. A negative correlation (p < 0.05) was found for growth rate with salinity, ammonium, nitrate, nitrite, and phosphate. No correlation was found with dissolved organic carbon, suggesting that Haliclona oculata is more dependent on particulate organic carbon. 相似文献