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We present a genome assembly from a specimen of Bugula neritina (the ruby bryozoan; Bryozoa; Gymnolaemata; Cheilostomatida; Bugulidae). The genome sequence has total length of 216.00 megabases. Most of the assembly is scaffolded into 9 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 15.25 kilobases in length. Gene annotation of this assembly on Ensembl identified 20,264 protein-coding genes.

Transgenerational plasticity (TGP)-when a parent or previous generation's environmental experience affects offspring phenotype without involving a genetic change-can be an important mechanism allowing for rapid adaptation. However, despite increasing numbers of empirical examples of TGP, there appears to be considerable variation in its strength and direction, yet limited understanding of what causes this variation. We compared patterns of TGP in response to stress across two populations with high versus low historical levels of stress exposure. Specifically, we expected that exposure to acute stress in the population experiencing historically high levels of stress would result in adaptive TGP or alternatively fixed tolerance (no parental effect), whereas the population with low levels of historical exposure would result in negative parental carryover effects. Using a common sessile marine invertebrate, Bugula neritina, and a split brood design, we exposed parents from both populations to copper or control treatments in the laboratory and then had them brood copper-naïve larvae. We then exposed half of each larval brood to copper and half to control conditions before allowing them to grow to maturity in the field. Maternal copper exposure had a strong negative carryover effect on adult offspring growth and survival in the population without historical exposure, especially when larvae themselves were exposed to copper. We found little to no maternal or offspring treatment effect on adult growth and survival in the population with a history of copper exposure. However, parents from this population produced larger larvae on average and were able to increase the size of their larvae in response to copper exposure, providing a potential mechanism for maintaining fitness and suggesting TGP through maternal provisioning. These results indicate that the ability to adjust offspring phenotype via TGP may be a locally adapted trait and potentially influenced by past patterns of exposure.

Marine natural products are promising sources of green antifoulants. Here, a new compound (1) was isolated from the soft coral Sinularia flexibilis. This compound, another nine cembranoids (2–10) from S. flexibilis, and three eunicellin-type diterpenoids (11–13) from the gorgonian Muricella sp. were tested for antifouling activity against larval settlement of the bryozoan Bugula neritina. Compounds 2, 3, 4, 9, 12, and 13 exhibited significant antifouling activity, with EC50 values of 18.2, 99.7, 67.9, 35.6, 33.9, and 49.3 μM, respectively. Analysis of the structure-activity relationships suggested that the hydroxy group at C-13 in compound 4 reduced its antifouling activity. [ABSTRACT FROM AUTHOR]

Abstract Transgenerational plasticity (TGP)—when a parent or previous generation's environmental experience affects offspring phenotype without involving a genetic change—can be an important mechanism allowing for rapid adaptation. However, despite increasing numbers of empirical examples of TGP, there appears to be considerable variation in its strength and direction, yet limited understanding of what causes this variation. We compared patterns of TGP in response to stress across two populations with high versus low historical levels of stress exposure. Specifically, we expected that exposure to acute stress in the population experiencing historically high levels of stress would result in adaptive TGP or alternatively fixed tolerance (no parental effect), whereas the population with low levels of historical exposure would result in negative parental carryover effects. Using a common sessile marine invertebrate, Bugula neritina, and a split brood design, we exposed parents from both populations to copper or control treatments in the laboratory and then had them brood copper‐naïve larvae. We then exposed half of each larval brood to copper and half to control conditions before allowing them to grow to maturity in the field. Maternal copper exposure had a strong negative carryover effect on adult offspring growth and survival in the population without historical exposure, especially when larvae themselves were exposed to copper. We found little to no maternal or offspring treatment effect on adult growth and survival in the population with a history of copper exposure. However, parents from this population produced larger larvae on average and were able to increase the size of their larvae in response to copper exposure, providing a potential mechanism for maintaining fitness and suggesting TGP through maternal provisioning. These results indicate that the ability to adjust offspring phenotype via TGP may be a locally adapted trait and potentially influenced by past patterns of exposure.

We present a genome assembly from a specimen of Bugula neritina (the ruby bryozoan; Bryozoa; Gymnolaemata; Cheilostomatida; Bugulidae). The genome sequence has total length of 216.00 megabases. Most of the assembly is scaffolded into 9 chromosomal pseudomolecules. The mitochondrial genome has also been assembled and is 15.25 kilobases in length. Gene annotation of this assembly on Ensembl identified 20,264 protein-coding genes., Competing Interests: No competing interests were disclosed., (Copyright: © 2024 Uhl R et al.)

Abstract Kin associations increase the potential for inbreeding. The potential for inbreeding does not, however, make inbreeding inevitable. Numerous factors influence whether inbreeding preference, avoidance, or tolerance evolves, and, in hermaphrodites where both self‐fertilization and biparental inbreeding are possible, it remains particularly difficult to predict how selection acts on the overall inbreeding strategy, and to distinguish the type of inbreeding when making inferences from genetic markers. Therefore, we undertook an empirical analysis on an understudied type of mating system (spermcast mating in the marine bryozoan, Bugula neritina) that provides numerous opportunities for inbreeding preference, avoidance, and tolerance. We created experimental crosses, containing three generations from two populations to estimate how parental reproductive success varies across parental relatedness, ranging from self, siblings, and nonsiblings from within the same population. We found that the production of viable selfed offspring was extremely rare (only one colony produced three selfed offspring) and biparental inbreeding more common. Paternity analysis using 16 microsatellite markers confirmed outcrossing. The production of juveniles was lower for sib mating compared with nonsib mating. We found little evidence for consistent inbreeding, in terms of nonrandom mating, in adult samples collected from three populations, using multiple population genetic inferences. Our results suggest several testable hypotheses that potentially explain the overall mating and dispersal strategy in this species, including early inbreeding depression, inbreeding avoidance through cryptic mate choice, and differential dispersal distances of sperm and larvae.

In the search for new medicines, no realm of the globe holds more intrigue than that of the sea. Many of the more complex, novel and interestingc ompounds discovered in the last decade have been extracted from marine organisms—typically soft corals and sponges, marine algae, even bacteria.

This dissertation investigates the identity and function of a bacterial symbiont described in the marine bryozoan Bugula neritina by R.M. Woollacott in 1981. B. neritina is the source of bryostatins, unique cytotoxins suspected to have a bacterial source, and is considered a single species throughout its cosmopolitan temperate range. Bryostatins found from different collections of B. neritina vary, and only certain populations produce bryostatins that possess an octa-2,4-dienoate substituent. In this dissertation the bacterial symbionts of the larvae are identified by small subunit ribosomal rRNA {SSU) gene sequences and named "Candidatus Endobugula sertula." The variable regions of these genes were used to design oligonucleotides specific to the symbiont. These specific oligonucleotides were used for in situ hybridization to the bacteria in the pallial sinus to confirm the origin of the sequence, and for specific amplification of symbiont SSU rRNA genes by PCR. Then the mitochondrial cytochrome c oxidase subunit I gene was used to identify two distinct species of B. neritina each harboring a different symbiont as determined by SSU rRNA sequence. Variation in the bryostatin profiles is associated with this genetic difference. Only one B. neritina/"E. sertula" association can produce bryostatins with an octa-2,4-dienoate substituent (bryostatins 1-3, 12 and 15). In order to elucidate the possible involvement of the symbiont in production of bryostatins, experiments were conducted to eliminate "E. sertula" from R. neritina to determine whether B. neritina can continue to grow normally without the symbiont, and/or continue to produce equivalent levels of bryostatins. Symbiont levels were estimated using a symbiont-specific PCR assay, then bryostatin activity levels were compared between control and treated B. neritina colonies. When symbiont levels were greatly reduced, bryostatin activity declined by approximately 50%. Genetic evidence was discovered that indicates "E. sertuld" has the potential to synthesize complex polyketides like bryostatin. Finally evidence was gathered to address the hypothesis that bryostatins serve as defensive compounds for the bryozoan host. The distribution of bryostatins in the colonies is suggestive of a defense, and it was found that predatory nudibranchs of B. neritina sequester bryostatins and concentrate them in their egg ribbons. In summary, the symbiont's most likely function is to provide a chemical defense, bryostatins, for the host.

Kin associations increase the potential for inbreeding. The potential for inbreeding does not, however, make inbreeding inevitable. Numerous factors influence whether inbreeding preference, avoidance, or tolerance evolves, and, in hermaphrodites where both self‐fertilization and biparental inbreeding are possible, it remains particularly difficult to predict how selection acts on the overall inbreeding strategy, and to distinguish the type of inbreeding when making inferences from genetic markers. Therefore, we undertook an empirical analysis on an understudied type of mating system (spermcast mating in the marine bryozoan, Bugula neritina) that provides numerous opportunities for inbreeding preference, avoidance, and tolerance. We created experimental crosses, containing three generations from two populations to estimate how parental reproductive success varies across parental relatedness, ranging from self, siblings, and nonsiblings from within the same population. We found that the production of viable selfed offspring was extremely rare (only one colony produced three selfed offspring) and biparental inbreeding more common. Paternity analysis using 16 microsatellite markers confirmed outcrossing. The production of juveniles was lower for sib mating compared with nonsib mating. We found little evidence for consistent inbreeding, in terms of nonrandom mating, in adult samples collected from three populations, using multiple population genetic inferences. Our results suggest several testable hypotheses that potentially explain the overall mating and dispersal strategy in this species, including early inbreeding depression, inbreeding avoidance through cryptic mate choice, and differential dispersal distances of sperm and larvae. [ABSTRACT FROM AUTHOR]

Abstract The increasing number of anthropogenic areas in the marine environment results in significant impact to adjacent ecosystems. In fact, the presence of marinas modifies the original environmental conditions and ends up disturbing the faunal community. However, despite the essential role displayed by the macrofauna on marinas' fouling biota, certain taxa such as polychaetes have been poorly studied. The present study provides the first spatial characterization of the epibiont polychaete fauna associated with the bryozoan Bugula neritina in marinas along the Iberian Peninsula and the north of Morocco. A total of 32 polychaete species were identified, with Syllidae being the most diverse family. Furthermore, the environmental factors involved in the occurrence and abundance of the dominant species Salvatoria clavata were also analyzed by Generalized Linear Models; results showed that the highest predicted values of S. clavata abundance appeared at marinas with high levels of nutrient enrichment and of heavy metals concentration. Highlights • A total of 32 polychaete species were found in the studied area. • Syllids were the dominant epibiont polychaete family in Iberian Peninsula marinas. • Pollutants were the most relevant factors in the polychaete assemblage structure. • Salvatoria clavata was the dominant polychaete associated to Bugula neritina. • Higher predicted values of S. clavata abundance occurred at more polluted marinas. [ABSTRACT FROM AUTHOR]

The bryozoan, Bugula neritina, is one of the most widespread sessile marine invasive species. Since its first discovery in Korea in 1978, the gradual increase in the distribution and abundance of this species resulted in a significant damage to growth of aquaculture. Environmental DNA (eDNA) is a potentially useful tool for species detection including rare, invasive and threatened native species. In this study, species-specific primers and probe were designed to amplify a 185−bp region based on mitochondrial COI of B. neritina for monitoring, and tested on environmental samples from 35 harbors of Korea in 2017. Among 35 sites monitored, B. neritina colonies were detected in 27 sites during field survey. However, B. neritina DNA was detected in all examined eDNA isolated from seawater. These results suggested that eDNA-based methods coupled with simple seawater sampling could be suitable for determining the distribution and abundance of B. neritina as complementary traditional monitoring. [ABSTRACT FROM AUTHOR]

The bryozoan Bugula neritina is a cosmopolitan marine fouling species that causes major fouling problems in sub-tropical waters. Settlement of B. neritina larvae can be triggered without an obvious external cue. Here, the negative regulatory role of nitric oxide (NO) during larval settlement of B. neritina was demonstrated to be mediated by cyclic guanosine monophosphate (cGMP). Although the regulatory role of the NO-p38 MAPK signaling axis in larval settlement was not evident, inhibition of nitric oxide synthase (NOS) led to the deactivation of p38 MAPK. Exclusive localization of NO and NO signaling components in sensory-related organs of the larvae is consistent with its signal transduction function in metamorphosis. Overall, this study provides new insights into the regulatory roles of the NO-p38MAPK/cGMP pathway in B. neritina settlement. [ABSTRACT FROM AUTHOR]

Five new ceramides, neritinaceramides A (1), B (2), C (3), D (4) and E (5), together with six known ceramides (6–11), two known alkyl glycerylethers (12 and 13) and a known nucleoside (14), were isolated from marine bryozoan Bugula neritina, which inhabits the South China Sea. The structures of the new compounds were elucidated as (2S,3R,3′S,4E,8E,10E)-2-(hexadecanoylamino)-4,8,10-octadecatriene-l,3,3′-triol (1), (2S,3R,2′R,4E,8E,10E)-2-(hexadecanoylamino)-4,8,10-octadecatriene-l,3,2′-triol (2), (2S,3R,2′R,4E,8E,10E)-2-(octadecanoylamino)-4,8,10-octadecatriene-l,3,2′-triol (3), (2S,3R,3′S,4E,8E)-2-(hexadecanoylamino)-4,8-octadecadiene-l,3,3′-triol (4) and (2S,3R,3′S,4E)-2-(hexadecanoylamino)-4-octadecene-l,3,3′-triol (5) on the basis of extensive spectral analysis and chemical evidences. The characteristic C-3′S hydroxyl group in the fatty acid moiety in compounds 1, 4 and 5, was a novel structural feature of ceramides. The rare 4E,8E,10E-triene structure in the sphingoid base of compounds 1–3, was found from marine bryozoans for the first time. The new ceramides 1–5 were evaluated for their cytotoxicity against HepG2, NCI-H460 and SGC7901 tumor cell lines, and all of them exhibited selective cytotoxicity against HepG2 and SGC7901 cells with a range of IC50 values from 47.3 μM to 58.1 μM. These chemical and cytotoxic studies on the new neritinaceramides A–E (1–5) added to the chemical diversity of B. neritina and expanded our knowledge of the chemical modifications and biological activity of ceramides.

A list of thirty-seven non-indigenous species (NIS) or cryptogens likely to appear on marinas or pontoons were targeted during a ten-day survey in 2012 on the north Irish coast. This included four bryozoan species. The non-targeted cryptogen, Bugulina fulva, was found for the first time in the Republic of Ireland. The bryozoans Bugula neritina and Watersipora subatra were found within Northern Ireland for the first time. The survey demonstrated that a rapid approach to sampling marinas and pontoons provides new range records of species likely to occur elsewhere within the region. [ABSTRACT FROM AUTHOR]

To control the spread of non-indigenous species it is necessary to understand how early stages of the invasion process, such as age of propagule at time of entrainment and transport, influence the quality and quantity of propagules delivered to recipient environments (i.e., the propagule pressure). Using ship biofouling as a model pathway scenario and the bryozoan Bugula neritina, the effect of two early-stage selective filters-the age of recruits and the pattern of the voyage-on reproductive output post-arrival were examined. Voyage scenarios were created by manipulating food levels in a series of field experiments. Recruit Age had three levels (1-day, 1-week and 1-month), and Voyage Pattern (four levels) represented vessels that undertake frequent short voyages or infrequent long voyages, plus control treatments. Spawning success, number of larvae and larval size were measured over multiple spawning events after each scenario. One-day and 1-week old colonies that had been exposed to short-voyage scenarios had higher reproductive output than those that had been exposed to longer and less frequent voyages. In contrast, 1-month old colonies did not release larvae under any voyage scenario. The survivorship of bryozoans in all treatments was relatively high, but reproductive output was influenced by colony age and voyage type. Our results suggest that vessels undergoing frequent, short intra-coastal or domestic voyages are able to deliver viable propagules to subsequent destinations even if they have prior port residencies as short as 1 day. At least for bryozoans, juvenile recruits may even pose a higher risk of spread compared to reproductively mature recruits. [ABSTRACT FROM AUTHOR]

In the present study, seven cembrane diterpenes were isolated from the soft coral Sinularia flexibilis by Toyopearl HW-40 column chromatography and High Performance Liquid Chromatography (HPLC). The diterpenes were identified as epoxycembrane A ( 1 ), sinularin ( 2 ), sinulariolide ( 3 ), (1 R ,13 S ,12 S ,9 S ,8 R ,5 S ,4 R )-9-acetoxy-5,8:12,13-diepoxycembr-15(17)-en-16,4-olide ( 4 ), 11-dehydrosinulariolide ( 5 ), (−)14-deoxycrassin ( 6 ) and dihydrosinularin ( 7 ). The antifouling activity of these compounds was examined by settlement assays, using the larvae of the bryozoan Bugula neritina and the barnacle Balanus albicostatus . With the exception of compound 2 , all compounds indicated significant antifouling activity and a variety of EC 50 values. In particular, compound 6 exhibited remarkable anti-settlement activity against the two biofoulers (EC 50 for B. neritina 3.90 μg ml −1 ; EC 50 for B. albicostatus 21.26 μg ml −1 ) as well as low toxicity against B. albicostatus larvae (LC 50 > 100 μg ml −1 ), suggesting its potential as an environmentally friendly antifoulant. This is the first report on the antifouling activity of compounds 1 and 4 – 7 , further demonstrating the involvement of cembrane diterpenes in the chemical defense of soft corals against surface fouling. [ABSTRACT FROM AUTHOR]

Some species of invertebrates especially bryozoans (Bryozoa syn. Ectoprocta) and marine sponges (Porifera) are very important sources of pharmacologically exploitable compounds. These substances are probably produced to protect themselves from fish predators and may be an advantage in competition. The real sources of compounds with these antipredatory effects are probably not marine invertebrates themselves, but microscopic symbionts or food which they feed on. Bryostatins from bryozoan species Bugula neritina are produced by a bacterial symbiont called Candidatus Endobugula sertula. They have significant anti-cancer effects, but also other therapeutic benefits. Compounds with the structure of bryostatins were also discovered in some other invertebrates. Sponges are a source of many compounds, e.g., ara-A (vidarabine), manzamine, lasonolides, spongistatins, peloruside and others with antimicrobial, anti-cancer, immunosuppressive and similar activities. Other important sources of compounds with medical effects are tunicates (Tunicata syn. Urochordata) and some snails (Mollusca). One drug was developed from tunicates - Yondelis against refractory soft-tissue sarcomas. Certain other drugs originate from snails: e.g., prialt, which acts against chronic pain in spinal cord injury.

Bugula neritina is a sessile marine bryozoan with a pelagic larval stage. Larvae frequently settle on boat hulls, facilitating the introduction of B. neritina to bays and estuaries worldwide. Adrenergic agonists, such as norepinephrine, inhibit larval settlement in a variety of marine invertebrate species, including B. neritina . Light also inhibits larval settlement of B. neritina , yet the underlying mechanisms by which light and adrenergic compounds exert their effects on larvae are largely unknown. Octopamine is considered the invertebrate analog of norepinephrine, and may be one endogenous compound involved in larval settlement pathways. In this study, we investigated the effects of norepinephrine and the adrenergic antagonist phentolamine on larval settlement, and found that norepinephrine inhibited larval attachment and increased larval swimming behavior, while phentolamine increased larval attachment and decreased larval swimming behavior. We used fluorescent labeling and immunocytochemistry to localize sensory system components, and found that larvae possess adrenergic-like receptors and octopamine-like immunoreactivity. We also exposed larvae to phentolamine in both dark and light conditions, and found that light inhibited larval attachment, but phentolamine blocked those inhibitory effects. Based on these results, we put forth a putative mechanistic explanation for the effects of both light and adrenergic compounds on B. neritina larval settlement behavior. This study sheds light on previously unknown pathways underlying larval settlement behavior of bryozoans, and may aid in the development of effective, non-toxic biofouling control strategies. [ABSTRACT FROM AUTHOR]

Bryostatin-1 is a marine natural product that has demonstrated medicinal activity in pre-clinical and clinical trials for the treatment of cancer, Alzheimer’s disease, effects of stroke, and HIV. In this study, iron–bryostatin-1 was obtained using a pharmaceutical aquaculture technique developed by our lab that cultivates marine bacteria for marine natural product extraction. Analytical measurements 1 H and 13 C NMR, mass spectrometry, and flame atomic absorption were utilized to confirm the presence of an iron–bryostatin-1 complex. The iron–bryostatin-1 complex produced was then tested against the National Cancer Institute’s 60 cell line panel. Adding iron to bryostatin-1 lowered the anti-cancer efficacy of the compound. [ABSTRACT FROM AUTHOR]

From 29 June to 25 July 2014, scientists from Heriot Watt University and the Natural History Museum, London, aboard the vessel MV Halton, undertook a research cruise along the Norwegian coast. The cruise started in Bergen and over the two-week period surveys were conducted at intervals along the coastline, heading northwards, and including the major ports of Ålesund, Kristiansund, and Trondheim. When the vessel moored up in each harbour, surveys of the local pontoons were conducted to identify fouling species and to ascertain whether any non-native Bryozoa were present. Seven species of fouling Bryozoa were identified. Two of these were the non-native species Tricellaria inopinata d'Hondt and Occhipinti Ambrogi, 1985 and Schizoporella japonica Ortmann, 1890. This study represents the first confirmed records for these species from Norwegian coastal waters. It is likely, given the locations of occurrence, that small boat traffic was a vector for the introduction of these species. Recommendations are given for the amendment and addition of species to the Norwegian Black List. [ABSTRACT FROM AUTHOR]

Much of our understanding of competition comes from observations in sessile systems, such as rainforests and marine invertebrate communities. In terrestrial systems, sessile species often compete for multiple limiting resources (i.e., space, light, and nutrients), but in marine systems, space is viewed as the primary or sole limiting resource. Competition theory, on the other hand, suggests that competition for a single limiting resource is unlikely to maintain high species diversity, but manipulative tests of competition for other resources in marine benthic systems are exceedingly rare. Here, we manipulate the availability of food for a classic system, marine sessile invertebrate communities, and investigate the effects on species diversity, abundance, and composition during early succession as well as on the growth of bryozoan populations in the field. We found the number of species to be greater, available space to be lower, and the community composition to be different in assemblages subjected to increased food availability compared to controls. Similarly, laboratory-settled bryozoans deployed into the field grew more in the presence of enhanced food. Our results suggest that food can act as a limiting resource, affecting both diversity and abundance, even when bare space is still available in hard-substratum communities. Consequently, broadening the view of resource limitation beyond solely space may increase our understanding and predictability of marine sessile systems. [ABSTRACT FROM AUTHOR]

Two new sterols, (22E)-cholest-4,22-diene-3β,6β-diol (1) and (23S,24R)-dimethylcholest-7-ene-3β, 5α,6β-triol (3), a sterol reported for the first time from natural sources, (22E,24S)-24-methylcholest-4,22-diene-3β,6β-diol (2), together with a known steroid glycoside (4) and six known sterols (5-10), were isolated from the marine bryozoan Bugula neritina inhabiting South China Sea. The structures of the new compounds were determined on the basis of extensive spectral analysis, including 1D and 2D NMR, EI-MS, HR-EI/ESI-MS data. Compounds 1-10 were evaluated for their cytotoxicity against human tumor cell lines HepG2, NCI-H460 and SGC7901. Sterols 1, 2 and 5 exhibited selective inhibitions against HepG2 cancer cell line with the IC50 values of 36.6 µM, 52.1 µM and 47.8 µM, respectively, while showed inactivity to NCI-H460 and SGC7901 cell lines. The characteristic 3β,6β-dihydroxy Δ4 nucleus in sterols 1, 2 and 5 was found from marine bryozoans for the first time. [ABSTRACT FROM AUTHOR]

The major theories regarding the combined influence of the environment and species interactions on population and community dynamics appear to conflict. Stress/ disturbance gradient models of community organization, such as the stress gradient hypothesis, emphasize a diminished role for competition in harsh environments whereas modern coexistence theory does not. Confusion about the role of species interactions in harsh environments is perpetuated by a disconnect between population dynamics theory and data. We linked theory and data using response surface experiments done in the field to parameterize mathematical, population-dynamic competition models. We replicated our experiment across two environments that spanned a common and important environmental stress gradient for determining community structure in benthic marine systems. We generated quantitative estimates of the effects of environmental stress on population growth rates and the direction and strength of intra- and interspecific interactions within each environment. Our approach directly addressed a perpetual blind spot in this field by showing how the effects of competition can be intensified in stressful environments even though the apparent strength of competition remains unchanged. Furthermore, we showed how simultaneous, reciprocal competitive and facilitative effects can stabilize population dynamics in multispecies communities in stressful environments. [ABSTRACT FROM AUTHOR]

Abstract: Being physically unprotected sessile organisms, marine sponges are thought to protect themselves from surface fouling through the use of antifouling secondary metabolites. In this study, the sponge Axinella sp. was extracted with methanol and then partitioned between organic solvents and water. Two main compounds, hymenialdisine (HD) and debromohymenialdisine (DBH), were isolated from the n-BuOH layer using Sephadex LH-20 and C-18 column chromatography. The antifouling activity of HD and DBH were evaluated using the test of byssus thread production with the green mussel Perna viridis, and the settlement assays with the bryozoan Bugula neritina larvae and the green alga Ulva prolifera spores. Both HD and DBH were found to exhibit significant antifouling activities against P. viridis (EC50 values of 31.77 and 138.18 μg ml−1, respectively), B. neritina (EC50 values of 3.43 and 8.17 μg ml−1, respectively) and U. prolifera (EC50 values of 8.31 and 0.67 μg ml−1, respectively). Our results suggested that HD and DBH may play a role in chemical defense against fouling in Axinella sp. [Copyright &y& Elsevier]

Polydimethylsiloxane surfaces textured with a square-wave linear grating profile (0, 20, 200, 300 and 600 μm), and embedded with a range of photocatalytic titanium dioxide (TiO2) nanoparticle loadings (3.75, 7.5, 11.25 and 15 wt.%), were used to test the combined efficacy of these technologies as antifouling materials. Settlement of the fouling bryozoan speciesBugula neritinawas quantified in the laboratory under two intensities of UV light. The lowest settlement rates were observed on 20 μm surfaces. However, texture effects were not as critical to larval settlement as the presence of TiO2. In conjunction with UV light, TiO2completely inhibited larval metamorphosis even at the lowest loading (3.75 wt.%) and the lowest intensity of UV light (24 W m−2). Recruitment ofB. neritinawas also quantified in field trials and showed similar results to laboratory assays. The lowest recruitment was observed on 20 and 200 μm surfaces, with recruitment being significantly lower on all surfaces containing TiO2. Therefore forB. neritina, although all TiO2loadings were effective, 3.75 wt.% can be used as a minimum inhibitory concentration to deter larval settlement and the addition of a 20 μm texture further increases the deterrent effect. [ABSTRACT FROM AUTHOR]

Marine larvae are often considered as drifters that collide with larval collectors as passive particles. The trajectories of Bugula neritina larvae and of polystyrene beads were recorded in the velocity field of a vertical cylinder. The experiments illustrated that the trajectories of larvae and of beads may differ markedly. By considering a larva as a self-propelled mechanical microswimmer, a mathematical model of its motion in the two-dimensional velocity field of a long cylinder was formulated. Simulated larval trajectories were compared with experimental observations. We calculated the ratio η of the probability of contact of a microswimmer with a cylinder to the probability of contact of a passive particle with the cylinder. We found that depending on the ratio S of the swimming velocity of the microswimmer to the velocity of the ambient current, the probability of contact of a microswimmer with a collector may be orders of magnitude larger than the probability of contact of a passive particle with the cylinder: for S=0.01, η=1; for S=0.1, η=10; and for S=1, η=100. [ABSTRACT FROM AUTHOR]

Augmentative biocontrol, defined as the use of indigenous natural enemies to control pest populations, has not been explored extensively in marine systems. This study tested the potential of the anemoneAnthothoe albocinctaas a biocontrol agent for biofouling on submerged artificial structures. Biofouling biomass was negatively related to anemone cover. Treatments with high anemone cover (>35%) led to significant changes in biofouling assemblages compared to controls. Taxa that contributed to these changes differed among sites, but included reductions in cover of problematic fouling organisms, such as solitary ascidians and bryozoans. In laboratory trials,A. albocinctasubstantially prevented the settlement of larvae of the bryozoanBugula neritinawhen exposed to three levels of larval dose, suggesting predation as an important biocontrol mechanism, in addition to space pre-emption. This study demonstrated that augmentative biocontrol using anemones has the potential to reduce biofouling on marine artificial structures, although considerable further work is required to refine this tool before its application. [ABSTRACT FROM AUTHOR]

Abstract: The stereoselective synthesis of C1–C10 fragment of cytostatic macrolide bryostatin is described. Two of the three chiral centers have been established via the Sharpless kinetic resolution of racemic allylic alcohol 15 followed by regioselective reduction of epoxy alcohol 8 with Red-Al. Diastereoselective Aldol reaction of an aldehyde 7 with methyl isobutyrate affords the corresponding β-hydroxyester 23 which is then transformed into tetrahydropyran ring system 3 via an intramolecular hemi-ketalization. [Copyright &y& Elsevier]

Despite the importance of dispersal for population connectivity, dispersal is often costly to the individual. A major impediment to understanding connectivity has been a lack of data combining the movement of individuals and their survival to reproduction in the new habitat (realized connectivity). Although mortality often occurs during dispersal (an immediate cost), in many organisms costs are paid after dispersal (deferred costs). It is unclear how such deferred costs influence the mismatch between dispersal and realized connectivity. Through a series of experiments in the field and laboratory, we estimated both direct and indirect deferred costs in a marine bryozoan (Bugula neritina). We then used the empirical data to parameterize a theoretical model in order to formalize predictions about how dispersal costs influence realized connectivity. Individuals were more likely to colonize poor-quality habitat after prolonged dispersal durations. Individuals that colonized poor-quality habitat performed poorly after colonization because of some property of the habitat (an indirect deferred cost) rather than from prolonged dispersal per se (a direct deferred cost). Our theoretical model predicted that indirect deferred costs could result in nonlinear mismatches between spatial patterns of potential and realized connectivity. The deferred costs of dispersal are likely to be crucial for determining how well patterns of dispersal reflect realized connectivity. Ignoring these deferred costs could lead to inaccurate predictions of spatial population dynamics. [ABSTRACT FROM AUTHOR]

Some species of invertebrates especially bryozoans (Bryozoa syn. Ectoprocta) and marine sponges (Porifera) are very important sources of pharmacologically exploitable compounds. These substances are probably produced to protect themselves from fish predators and may be an advantage in competition. The real sources of compounds with these antipredatory effects are probably not marine invertebrates themselves, but microscopic symbionts or food which they feed on. Bryostatins from bryozoan species Bugula neritina are produced by a bacterial symbiont called Candidatus Endobugula sertula. They have significant anti-cancer effects, but also other therapeutic benefits. Compounds with the structure of bryostatins were also discovered in some other invertebrates. Sponges are a source of many compounds, e.g., ara-A (vidarabine), manzamine, lasonolides, spongistatins, peloruside and others with antimicrobial, anti-cancer, immunosuppressive and similar activities. Other important sources of compounds with medical effects are tunicates (Tunicata syn. Urochordata) and some snails (Mollusca). One drug was developed from tunicates - Yondelis against refractory soft-tissue sarcomas. Certain other drugs originate from snails: e.g., prialt, which acts against chronic pain in spinal cord injury. [ABSTRACT FROM AUTHOR]

Two new oxygenated sterols, 3β,24(S)-dihydroxycholesta-5,25-dien-7-one (1) and 3β,25-dihydroxycholesta-5,23-dien-7-one (2), were isolated from the marine bryozoan Bugula neritina. Their chemical structures were established on the basis of spectroscopic analysis. Both compounds exhibited cytotoxicity to three human cancer cell lines (HepG2, HT-29 and NCI-H460), with IC50 values between 22.58 and 53.41 µg mL−1. [ABSTRACT FROM AUTHOR]

Butenolide [5-octylfuran-2(5H)-one] is a very promising antifouling compound. Here, the effects of butenolide on larval behavior and histology are compared in two major fouling organisms, viz. cypris larvae of Balanus amphitrite and swimming larvae of Bugula neritina. Butenolide diminished the positive phototactic behavior of B. amphitrite (EC50 = 0.82 μg ml-1) and B. neritina (EC50 = 3 μg ml-1). Its effect on the attachment of cyprids of B. amphitrite was influenced by temperature, and butenolide increased attachment of larvae of B. neritina to the bottom of the experimental wells. At concentrations of 4 μg ml-1 and 10 μg ml-1, butenolide decreased attachment of B. amphitrite and B. neritina, respectively, but the effects were reversible within a certain treatment time. Morphologically, butenolide inhibited the swelling of secretory granules and altered the rough endoplasmic reticulum (RER) in the cement gland of B. amphitrite cyprids. In B. neritina swimming larvae, butenolide reduced the number of secretory granules in the pyriform-glandular complex. [ABSTRACT FROM AUTHOR]

From the marine bryozoan Bugula neritina inhabiting South China Sea, a new ceramide named (2S,3R,4E)-2-(14'-methyl-pentadecanoylamino)-4-octadecene-l,3-diol (1) and a new cerebroside named 1-O-(β-d-glucopyranosyl)-(2S,3R,4E)-2-(heptadecanoylamino)-4-octadecene-l,3-diol (6), together with one known ceramide (2) and three known cerebrosides (3, 4, and 5), were isolated. Their structures were deduced by extensive spectral analysis and chemical evidences. Compound 1 is branched with a methyl [-CH(CH3)2] in the fatty acid moiety, which is a rare structural feature among ceramides. Compound 6 is a new cerebroside with 17 carbons in the fatty acid moiety, while 5 is a new natural product which was isolated from a natural origin for the first time. [ABSTRACT FROM AUTHOR]

Mizolastine, an antihistamine pharmaceutical, was found to significantly inhibit larval settlement of the barnacle Amphibalanus (=Balanus) amphitrite, the bryozoan Bugula neritina, and the polychaete Hydroides elegans with EC50 values of 4.2, 11.2, and 4.1 µg ml-1, respectively. No toxicity against the larvae of these three species was observed at the concentration range tested during incubations with mizolastine. To determine whether the anti-settlement activity of mizolastine is reversible, recovery bioassays using these three species were conducted. More than 70% of the larvae that had been exposed for 4 h to mizolastine at concentrations four-fold greater than their respective EC50 values completed normal metamorphosis. The results of the recovery bioassay provide evidence that the anti-settlement effect of mizolastine is reversible in addition to being nontoxic. The anti-settlement activities of several intermediates of the synthesis process of mizolastine were also examined. One of the intermediates, 2-chloro-1-(4-fluorobenzyl)-1H-benzo[d]imidazole, inhibited larval settlement and metamorphosis with low toxicity. These results may improve the understanding of the key functional group responsible for the anti-settlement activity of mizolastine. [ABSTRACT FROM AUTHOR]

Abstract: Scallop aquaculture in Chile suffers from intense fouling on culture facilities by invasive species such as the ascidian Ciona intestinalis and the bryozoan Bugula neritina. We examined the grazing effect of the rock shrimp Rhynchocinetes typus on fouling species, which colonize scallop pearl nets. We placed different densities of shrimp (0, 2, 5 and 10 individuals) in pearl nets with juvenile scallops (mean shell height 4.9 cm) at Tongoy Bay in northern-central Chile. We sampled the nets after 4 months (January–May 2007) and recovered 35–50% of the shrimp from the different treatments. The nets with 10 initial shrimp had a lower cover of the bryozoan B. neritina and lower densities of the ascidians C. intestinalis and Pyura chilensis, which resulted in a 50% decrease in biomass of fouling on nets. Low scallop mortality and slightly higher (yet not significant) growth in treatments with high shrimp densities suggest a positive interaction between the shrimp and scallops. The native rock shrimp is therefore considered a good candidate as a biological control of fouling communities and this could have a potential for polyculture. [Copyright &y& Elsevier]