The TATA-binding Protein DNA-binding domain of eukaryotic parasites is a potentially druggable target.

The TATA-binding protein (TBP) is a central transcription factor in eukaryotes that interacts with a large number of different transcription factors; thus, affecting these interactions will be lethal for any living being. In this work, we present the first structural and dynamic computational study of the surface properties of the TBP DNA-binding domain for a set of parasites involved in diseases of worldwide interest. The sequence and structural differences of these TBPs, as compared with human TBP, were proposed to select representative ensembles generated from molecular dynamics simulations and to evaluate their druggability by molecular ensemble-based docking of drug-like molecules. We found that potential druggable sites correspond to the NC2-binding site, N-terminal tail, H2 helix, and the interdomain region, with good selectivity for Plasmodium falciparum, Necator americanus, Entamoeba histolytica, Candida albicans, and Taenia solium TBPs. The best hit compounds share structural similarity among themselves and have predicted dissociation constants ranging from nM to µM. These can be proposed as initial scaffolds for experimental testing and further optimization. In light of the obtained results, we propose TBP as an attractive therapeutic target for treatment of parasitic diseases.

Steroid Sulfates from Ophiuroids (Brittle Stars): Action on Some Factors of Innate and Adaptive Immunity.

The action of seven polyhydroxylated sterol mono- and disulfates (1-7), isolated from ophiuroids, on innate and adaptive immunity was examined in in vitro and in vivo experiments. At least, three of them (1, 2 and 4) increased the functional activities of neutrophils, including levels of oxygen-dependent metabolism, adhesive and phagocytic properties, and induced the expression of pro-inflammatory cytokines TNF-α and IL-8. Compound 4 was the most active for enhancing the production of antibody forming cells in the mouse spleen.

Mechanism of p27 Unfolding for CDK2 Reactivation.

Cell-cycle regulatory protein, CDK2 is active when bound to its complementary partner protein, CyclinA or E. Recent discovery of the Kip/Cip family of proteins has indicated that the activity of CDK2 is also regulated by a member protein, p27. Although, the mechanism of CDK2 inhibition by p27 binding is known from crystal structure, little is known about the mechanism of CDK2 reactivation. Here, we execute classical and accelerated molecular dynamics simulations of unphosphorylated- and phosphorylated-p27 bound CDK2/CyclinA to unravel the CDK2 reactivation mechanism at molecular-to-atomic detail. Results suggest that the phosphorylation of p27 Y88 residue (pY88-p27) first disrupts the p27/CDK2 hybrid ß-sheet and subsequently ejects the p27 310 helix from CDK2 catalytic cleft. The unbinding of p27 from CDK2/CyclinA complex, thus, follows a two-step unfolding mechanism, where the 310 helix ejection constitutes the rate-limiting step. Interestingly, the unfolding of p27 leaves CDK2/CyclinA in an active state, where the prerequisite CDK2-CyclinA interfacial contacts were regained and ATP achieved its native position for smooth transfer of phosphate. Our findings match very well with NMR chemical shift data that indicated the flip-out of p27 310 helix from CDK2 pocket and kinetic experiments that exhibited significant kinase activity of CDK2 when saturated with pY88-p27.

A dietary polyunsaturated fatty acid improves consumer performance during challenge with an opportunistic bacterial pathogen.

A dietary deficiency in polyunsaturated fatty acids (PUFAs) and/or sterols can severely constrain growth and reproduction of invertebrate consumers. Single nutrients are potentially assigned to different physiological processes, for example to support defence mechanisms; therefore, lipid requirements of healthy and pathogen-challenged consumers might differ. In an oral exposure experiment, we explored the effects of dietary PUFAs and cholesterol on growth, reproduction and survival of an aquatic key herbivore (Daphnia magna) exposed to an opportunistic pathogen (Pseudomonas sp.). We show that healthy and pathogen-challenged D. magna are strongly albeit differentially affected by the biochemical composition of their food sources. Supplementation of a C20 PUFA-deficient diet with arachidonic acid (ARA) resulted in increased survival and reproduction of pathogen-challenged D. magna. We propose that the observed benefit of consuming an ARA-rich diet during pathogen challenge is conveyed partially via ARA-derived eicosanoids. This study is one of the first to consider the importance of dietary PUFAs in modifying fitness parameters of pathogen-challenged invertebrate hosts. Our results suggest that dietary PUFA supply should receive increased attention in host-microorganisms interactions and invertebrate disease models to better understand and predict disease dynamics in natural populations.

Shifting nutrient-mediated interactions between algae and bacteria in a microcosm: evidence from alkaline phosphatase assay.

The impacts of different nutrient additions (N + P, N + P + C, 4N + P, 4N + P + C, N + 2P) on the growth of algae and bacteria were studied in a microcosm experiment. Since alkaline phosphatase activity (APA) provides an indication of phosphorus deficiency, the higher value for algal APA in the treatments with excess nitrogen and for bacterial APA in the treatments with excess carbon suggested that, algal and bacterial phosphorus-limited status were induced by abundant nitrogen and carbon input, respectively. Bacterial phosphorus-limited status was weakened due to higher bacterial competition for phosphorus, compared to algae. In comparison with the bacterial and specific bacterial APA, higher values of algal and specific algal APA were found, which showed a gradual increase that coincided with the increase of chlorophyll a concentration. This fact indicated not only a stronger phosphorus demand by algae than by bacteria, but also a complementary relationship for phosphorus demand between algae and bacteria. However, this commensalism could be interfered by glucose input resulting in the decline of chlorophyll a concentration. Furthermore, the correlation between bacterial numbers and chlorophyll a concentration was positive in treatments without carbon and blurry in treatments with carbon. These observations validate a hypothesis that carbon addition can stimulate bacterial growth justifying bacterial nutrient demand, which decreases the availability of nutrients to algae and affects nutrient relationship between algae and bacteria. However, this interference would terminate after algal and bacterial adaption to carbon input.

Safety evaluation of Algal Oil from Schizochytrium sp.

The safety of Algal Oil from Schizochytrium sp. was evaluated by testing for gene mutations, clastogenicity and aneugenicity, and in a subchronic 90-day Sprague-Dawley rat dietary study. The results of all genotoxicity tests were negative. The 90-day study involved dietary exposure to 0.5, 1.5, and 5 wt.% of Algal Oil and two control diets: a standard low-fat basal diet and a basal diet supplemented with 5 wt.% menhaden oil (the fish oil control). There were no treatment-related effects of Algal Oil on clinical observations, body weight, food consumption, behavior, hematology, clinical chemistry, coagulation, or urinalysis parameters. Increased mean liver weights and alveolar histiocytosis were observed in both the fish oil control and the high-dose Algal Oil-treated animals and were not considered to be adverse. Algal Oil was bioavailable as demonstrated by the dose-related increase of DHA and EPA levels in tissues and plasma. The no observable adverse effect level (NOAEL) for Algal Oil under the conditions of this study was 5 wt.% in the diet, equivalent to an overall average Algal Oil intake of 3250 mg/kg bw/day for male and female rats. Based on the body surface area, the human equivalent dose is about 30 g Algal Oil/day for a 60 kg adult.

Safety and toxicological evaluation of AlgaeCal (AC), a novel plant-based calcium supplement.

The present study was conducted to examine the safety of a novel plant-based calcium supplement, derived from marine algae and containing high levels of calcium, magnesium, and other bone supporting minerals (commercially known as AlgaeCal (AC)). The present study evaluated the broad-spectrum safety of AC using a variety of toxicological assays including acute oral, acute dermal, primary skin irritation, and primary eye irritation toxicity. Under the conditions of the study, the acute oral LD(50) of AC was found to be greater than 5000 mg/kg body weight in rats, while the single acute dermal LD(50) was greater than 2000 mg/kg body weight. The primary skin irritation index of AC was found to be 0.4 and classified as slightly irritating to the skin. In primary eye irritation studies, the maximum mean total score of AC was observed to be 13.7 and classified as mildly irritating to the eye. Furthermore, another independent set of studies was conducted to obtain preliminary data for the teratogenic effects of AC in pregnant rats likely to arise from repeated gestational exposure, via oral gavage, over a test period of implantation through gestation (gestation days 5-19). Under the conditions of this pilot study, the effect of daily administration of AC by oral gavage at dose levels of 0, 500, 2500, and 5000 mg/kg/day during gestation days 5-19 of a 21-day pregnancy has appeared to result in no adverse toxicological effects to the pregnant rat or its developing offspring. A slight, non-significant increase in the incidence of incomplete sterna ossification (5(th) center) was observed. Under the conditions of the study, a no-observed-adverse effect level (NOAEL) of 5000 mg/kg/day of AC during pregnancy of the rat was observed. Overall, no significant toxicities of AC were observed in these toxicity models. Therefore, the results from the current study demonstrate a broad-spectrum safety profile of AC.

Distribution and abundance of MAAs in 33 species of microalgae across 13 classes.

We provide a direct comparison of the distribution and abundance of mycosporine-like amino acids (MAAs) in a diverse range of microalgal cultures (33 species across 13 classes) grown without supplementary ultraviolet radiation (UV). We compare the MAAs in cultures with those present in characterised natural phytoplankton populations from the English Channel. We detected 25 UV absorbing compounds including at least two with multiple absorption maxima. We used LC-MS to provide chemical characterisation of the six most commonly occurring MAAs, namely, palythene, palythine, mycosporine-glycine, palythenic acid, porphyra-334 and shinorine. MAAs were abundant (up to 7 pg MAA cell(-1)) in 10 species, with more minor and often unknown MAAs in a further 11 cultures. Shinorine was the most frequently occurring and abundant MAA (up to 6.5 pg cell(-1)) and was present in all but two of the MAA-containing species. The study provides further insight into the diversity and abundance of MAAs important from an ecological perspective and as potential source of natural alternatives to synthetic sunscreens.

In vitro potential of Ascophyllum nodosum phenolic antioxidant-mediated alpha-glucosidase and alpha-amylase inhibition.

Ascophyllum nodosum is a brown seaweed that grows abundantly in the Northeast coastal region. In this study, the potential of A. nodosum for type 2 diabetes management through antioxidant-mediated alpha-glucosidase and alpha-amylase inhibition was investigated. After the initial screening of 4 locally harvested seaweeds, A. nodosum was chosen for its highest phenolic content and was subjected to water extraction. Among extraction ratios of 50 g to 100 to 1000 mL at room temperature, 50 g/400 mL yielded the highest phenolic content of 4.5 mg/g wet weight. For evaluation of extraction temperature ranging from 20 to 80 degrees C, 50 g/400 mL was chosen as a minimum amount of extractant. Among temperatures studied, extraction at 80 degrees C resulted in the highest total phenolic contents (4.2 mg/g wet weight). All extracts had similar levels of antioxidant activity in the range of 60% to 70% in terms of 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity. The 80 degrees C extract had the highest alpha-glucosidase and alpha-amylase inhibitory activity with IC(50) of 0.24 and 1.34 microg phenolics, respectively, compared to the IC(50) of acarbose, reference inhibitor, being 0.37 and 0.68 microg. The results show that fresh A. nodosum has strong alpha-glucosidase and mild alpha-amylase inhibitory activities that correlated with phenolic contents. This study suggests a nutraceutical potential of A. nodosum based on phytochemical antioxidant and antihyperglycemia activities.

Effect of lyophilized water extracts of Melissa officinalis on the stability of algae and linseed oil-in-water emulsion to be used as a functional ingredient in meat products.

Previous work pointed out the possibility to enhance the nutritional value of meat products using long chain omega-3 PUFA enriched emulsions. Oil-in-water emulsions elaborated with a mixture of algae and linseed oils (15:10) in order to be used as functional ingredient were stabilized with BHA (butylhydroxyanisol) or with a lyophilized water extract of Melissa officinalis L. (Lemon balm). The lipid profile of the oil mixture showed a high amount of DHA (31.7%), oleic (25.4%) and alpha-linolenic acid (12.7%) resulting in a very low omega-6/omega-3 ratio (0.12). The lyophilized extract of M. officinalis showed a high antioxidant activity (being 62ppm of the lyophilized water extract of Melissa equivalent to 200ppm of BHA, using the DPPH assay as reference), and high total phenolic content. Studying the oxidation process in the emulsions during 15days at room temperature, it could be concluded that this extract was as efficient as BHA in order to control the thiobarbituric acid reactive substances (TBARS) formation.

Algal-based immobilization process to treat the effluent from a secondary wastewater treatment plant (WWTP).

Algal-based immobilization process was applied to treat the effluent from a secondary wastewater treatment plant. Batch test proved that algae could attach onto fiber-bundle carrier in 7 days, and then the algal-based immobilization reactor could reduce TN (total nitrogen) and TP (total phosphorus) significantly within 48 h. Based on the above investigations, the hydraulic retention time (HRT) of the algal-based immobilization reactor in continuous operation mode was determined to be 2 days. During the 91 days of experiment on the treating secondary effluent of Guang-Rao wastewater treatment plant, it was found that the fiber-bundle carrier could collect the heterobacteria and nitrifying bacteria gradually, and thus improved the COD removal efficiency and nitrification performance step by step. Results of the continuous operation indicated that the final effluent could meet the Chinese National First A-level Sewage Discharge Standard when the algal-based immobilization reactor reached steady state.

Inhibitory effect of diphlorethohydroxycarmalol on melanogenesis and its protective effect against UV-B radiation-induced cell damage.

In this study, potential inhibitory effect of 21 species of marine algae on melanogenesis was assessed via tyrosinase inhibitory effect. The Ishige okamurae extract tested herein evidenced profound tyrosinase inhibitory effect, compared to that exhibited by other marine algae extracts. Thus, I. okamurae was selected for use in further experiments, and was partitioned with different organic solvents. Profound tyrosinase inhibitory effect was detected in the ethyl acetate fraction, and the active compound was identified as the carmalol derivative, diphlorethohydroxycarmalol (DPHC), which evidenced higher levels of activity than that of commercial whitening agent. Intracellular reactive oxygen species (ROS) induced by ultraviolet (UV)-B radiation was reduced by the addition of DPHC and cell viability was dose-dependently increased. Moreover, DPHC demonstrated strong protective properties against UV-B radiation via damaged DNA tail length and morphological changes in fibroblast. Hence, these results indicate that DPHC isolated from I. okamurae has potential whitening effects and prominent protective effects on UV-B radiation-induced cell damages which might be used in pharmaceutical and cosmeceutical industries.

Comparative effects of a novel plant-based calcium supplement with two common calcium salts on proliferation and mineralization in human osteoblast cells.

Calcium is an essential mineral to support bone health and serves as a major therapeutic intervention to prevent and delay the incidence of osteoporosis. Many individuals do not obtain the optimum amount of calcium from diets and depend on bioavailable calcium supplements. The present study was conducted to examine the effect of a novel plant-based calcium supplement, derived from marine algae, and contains high levels of calcium, magnesium, and other bone supporting minerals [commercially known as AlgaeCal (AC)], on proliferation, mineralization, and oxidative stress in cultured human osteoblast cells, and compared with inorganic calcium carbonate and calcium citrate salts. Cultured human fetal osteoblast cells (hFOB 1.19) were treated with AC (0.5 mg/ml, fixed by MTT assay), calcium carbonate, or calcium citrate. These cells were harvested after 4 days of treatment for ALP activity, PCNA expression, and DNA synthesis, and 2 days for Ca(2+) deposition in the presence and absence of vitamin D3 (5 nM). The ability of AC to reduce H(2)O(2) (0.3 mM)-induced oxidative stress was assessed after 24 h of treatment. ALP activity was significantly increased with AC treatment when compared to control, calcium carbonate, or calcium citrate (4.0-, 2.0-, and 2.5-fold, respectively). PCNA expression (immunocytochemical analysis), DNA synthesis (4.0-, 3.0-, and 4.0-fold, respectively), and Ca(2+) deposition (2.0-, 1.0-, and 4.0-fold, respectively) were significantly increased in AC-treated cells when compared with control, calcium carbonate, or calcium citrate treatment. These markers were further enhanced following additional supplementation of vitamin D3 in the AC-treated group cells. AC treatment significantly reduced the H(2)O(2)-induced oxidative stress when compared to calcium carbonate or calcium citrate (1.5- and 1.4-fold, respectively). These findings suggest that AC may serve as a superior calcium supplement as compared to other calcium salts tested in the present study. Hence, AC may be developed as a novel anti-osteoporotic supplement in the near future.

Comparison of algal and fish sources on the oxidative stability of poultry meat and its enrichment with omega-3 polyunsaturated fatty acids.

Human consumption of long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) is below recommendations, and enriching chicken meat (by incorporating LC n-3 PUFA into broiler diets) is a viable means of increasing consumption. Fish oil is the most common LC n-3 PUFA supplement used but is unsustainable and reduces the oxidative stability of the mat. The objective of this experiment was to compare fresh fish oil (FFO) with fish oil encapsulated (EFO) in a gelatin matrix (to maintain its oxidative stability) and algal biomass at a low (LAG, 11), medium (MAG, 22), or high (HAG, 33 g/kg of diet) level of inclusion. The C22:6n-3 contents of the FFO, EFO, and MAG diets were equal. A control (CON) diet using blended vegetable oil was also made. As-hatched 1-d-old Ross 308 broilers (144) were reared (21 d) on a common starter diet then allocated to treatment pens (4 pens per treatment, 6 birds per pen) and fed treatment diets for 21 d before being slaughtered. Breast and leg meat was analyzed (per pen) for fatty acids, and cooked samples (2 pens per treatment) were analyzed for volatile aldehydes. Concentrations (mg/100 g of meat) of C20:5n-3, C22:5n-3, and C22:6n-3 were (respectively) CON: 4, 15, 24; FFO: 31, 46, 129; EFO: 18, 27, 122; LAG: 9, 19, 111; MAG: 6, 16, 147; and HAG: 9, 14, 187 (SEM: 2.4, 3.6, 13.1) in breast meat and CON: 4, 12, 9; FFO: 58, 56, 132; EFO: 63, 49, 153; LAG: 13, 14, 101; MAG: 11, 15, 102; HAG: 37, 37, 203 (SEM: 7.8, 6.7, 14.4) in leg meat. Cooked EFO and HAG leg meat was more oxidized (5.2 mg of hexanal/kg of meat) than the other meats (mean 2.2 mg/kg, SEM 0.63). It is concluded that algal biomass is as effective as fish oil at enriching broiler diets with C22:6 LC n-3 PUFA, and at equal C22:6n-3 contents, there is no significant difference between these 2 supplements on the oxidative stability of the meat that is produced.

Screening for bioactive compounds from algae.

In the present work, a comprehensive methodology to carry out the screening for novel natural functional compounds is presented. To do that, a new strategy has been developed including the use of unexplored natural sources (i.e., algae and microalgae) together with environmentally clean extraction techniques and advanced analytical tools. The developed procedure allows also estimating the functional activities of the different extracts obtained and even more important, to correlate these activities with their particular chemical composition. By applying this methodology it has been possible to carry out the screening for bioactive compounds in the algae Himanthalia elongata and the microalgae Synechocystis sp. Both algae produced active extracts in terms of both antioxidant and antimicrobial activity. The obtained pressurized liquid extracts were chemically characterized by GC-MS and HPLC-DAD. Different fatty acids and volatile compounds with antimicrobial activity were identified, such as phytol, fucosterol, neophytadiene or palmitic, palmitoleic and oleic acids. Based on the results obtained, ethanol was selected as the most appropriate solvent to extract this kind of compounds from the natural sources studied.

Subcritical water extraction and characterization of bioactive compounds from Haematococcus pluvialis microalga.

In this work, extraction and characterization of compounds with antioxidant and antimicrobial activity from Haematococcus pluvialis microalga in red phase have been carried out. To do this, subcritical water extraction (SWE) has been combined with analytical techniques such as HPLC-DAD, HPLC-QqQ-MS and GC-MS and in vitro assays (i.e., for antioxidant and antimicrobial activity). The effect of the extraction temperature (50, 100, 150 and 200 degrees C) and solvent polarity has been studied in terms of yield and activity of the extracts. Results demonstrate that the extraction temperature has a positive influence in the extraction yield and antioxidant activity. Thus, the extraction yield achieved with this process was higher than 30% of dry weight at 200 degrees C as extraction temperature. Moreover, the extract obtained at 200 degrees C presented the highest antioxidant activity by far, while temperature does not seem to significatively affect the antimicrobial activity. Chemical composition was determined by HPLC-DAD, HPLC-QqQ-MS and GC-MS. Short chain fatty acids turned out to be responsible of the antimicrobial activity, whereas the antioxidant activity was correlated to vitamin E (present exclusively in the 200 degrees C extract), together with simple phenols, caramelization products and possible Maillard reaction products obtained during the extraction at high temperatures.

Phosphorus-mediated changes in life history traits of the invasive New Zealand mudsnail (Potamopyrgus antipodarum).

Understanding the mechanisms that species use to succeed in new environments is vital to predicting the extent of invasive species impacts. Food quality is potentially important because it can affect population dynamics by affecting life history traits. The New Zealand mudsnail, Potamopyrgus antipodarum, is a worldwide invader. We examined how mudsnail growth rate and fecundity responded to the C:P ratio of algal food in laboratory conditions. Mudsnails fed low-P algae (C:P 1,119) grew more slowly, matured later, produced smaller offspring, and grew to a smaller adult size than snails reared on algae with high levels of P. A relatively small increase in algal C:P (203-270) significantly increased mudsnail age at maturity. We suggest that the relatively high body P requirements of mudsnails make them susceptible to allocation trade-offs between growth and reproduction under P-limited conditions. The elemental composition of algae varies greatly in nature, and over half of the rock biofilms in streams surveyed within the introduced range of mudsnails in the Greater Yellowstone Area had C:P ratios above which could potentially pose P limitation of life history traits. High growth rate and fecundity are common traits of many species that become invasive and are also associated with high-P demands. Therefore, fast-growing consumers with high P demands, such as mudsnails, are potentially more sensitive to P limitation suggesting that limitation of growth and reproduction by food quality is an important factor in understanding the resource demands of invasive species.

Land-based nutrient enrichment of the Buccoo Reef Complex and fringing coral reefs of Tobago, West Indies.

Tobago's fringing coral reefs (FR) and Buccoo Reef Complex (BRC) can be affected locally by wastewater and stormwater, and regionally by the Orinoco River. In 2001, seasonal effects of these inputs on water-column nutrients and phytoplankton (Chl a), macroalgal C:N:P and delta(15)N values, and biocover at FR and BRC sites were examined. Dissolved inorganic nitrogen (DIN, particularly ammonium) increased and soluble reactive phosphorus (SRP) decreased from the dry to wet season. Wet season satellite and Chl a data showed that Orinoco runoff reaching Tobago contained chromophoric dissolved organic matter (CDOM) but little Chl a, suggesting minimal riverine nutrient transport to Tobago. C:N ratios were lower (16 vs. 21) and macroalgal delta(15)N values higher (6.6 per thousand vs. 5.5 per thousand) in the BRC vs. FR, indicating relatively more wastewater N in the BRC. High macroalgae and low coral cover in the BRC further indicated that better wastewater treatment could improve the health of Tobago's coral reefs.

[Addendum and emendation of "China Medicinal Animal Fauna"].

UNLABELLED: To carry out the " China Medicinal Animal Fauna" addenda and revision, with effective assessment, protection, utilization of medicinal animal resources, to promote sustainable modem research and application for medicinal animals and medical materials from animals. METHOD: Keep the original "China Medicinal Animal Fauna" characteristics and peculiarities, combined with nearly 30-year research progress of zoology and medicinal animals, and author's long-standing and rich experience. RESULT: Develop the addenda's general framework, addenda and revision contents, revision methods and technical routes of the "China Medicinal Animal Fauna". CONCLUSION: Based on the research of medicinal animal resource system, fully use of modern molecular biology and other emerging science and technology, rich the scientific connotation of medicinal material from animal, will promote the research and use of medical material from animal to a new level.

Human exposure to cyanobacteria and BMAA.

Cyanobacteria are found worldwide, primarily in aquatic habitats. They are increasing in abundance as a result of increasing nutrient inputs from various human activities. Recent data indicate that most cyanobacteria produce the neurotoxin beta-N-methylamino-L-alanine (BMAA), and this toxin can biomagnify UP some food chains to rather high concentrations in animals used as food by humans. BMAA may pose an increasing human health risk.