Comparative genomics identifies key adaptive traits of sponge-associated microbial symbionts.

Sponge microbiomes are often highly diverse making it difficult to determine which lineages are important for maintaining host health and homeostasis. Characterising genomic traits associated with symbiosis can improve our knowledge of which lineages have adapted to their host and what functions they might provide. Here we examined five microbial families associated with sponges that have previously shown evidence of cophylogeny, including Endozoicomonadaceae, Nitrosopumilaceae, Spirochaetaceae, Microtrichaceae and Thermoanaerobaculaceae, to better understand the mechanisms behind their symbiosis. We compared sponge-associated genomes to genomes found in other environments and found that sponge-specific clades were enriched in genes encoding many known mechanisms for symbiont survival, such as avoiding phagocytosis and defence against foreign genetic elements. We expand on previous knowledge to show that glycosyl hydrolases with sulfatases and sulfotransferases likely form multienzyme degradation pathways to break and remodel sulfated polysaccharides and reveal an enrichment in superoxide dismutase that may prevent damage from free oxygen radicals produced by the host. Finally, we identified novel traits in sponge-associated symbionts, such as urea metabolism in Spirochaetaceae which was previously shown to be rare in the phylum Spirochaetota. These results identify putative mechanisms by which symbionts have adapted to living in association with sponges.

Metabolic reconstruction of the near complete microbiome of the model sponge Ianthella basta.

Many marine sponges host highly diverse microbiomes that contribute to various aspects of host health. Although the putative function of individual groups of sponge symbionts has been increasingly described, the extreme diversity has generally precluded in-depth characterization of entire microbiomes, including identification of syntrophic partnerships. The Indo-Pacific sponge Ianthella basta is emerging as a model organism for symbiosis research, hosting only three dominant symbionts: a Thaumarchaeotum, a Gammaproteobacterium, and an Alphaproteobacterium and a range of other low abundance or transitory taxa. Here, we retrieved metagenome assembled genomes (MAGs) representing >90% of I. basta's microbial community, facilitating the metabolic reconstruction of the sponge's near complete microbiome. Through this analysis, we identified metabolic complementarity between microbes, including vitamin sharing, described the importance of low abundance symbionts, and characterized a novel microbe-host attachment mechanism in the Alphaproteobacterium. We further identified putative viral sequences, highlighting the role viruses can play in maintaining symbioses in I. basta through the horizontal transfer of eukaryotic-like proteins, and complemented this data with metaproteomics to identify active metabolic pathways in bacteria, archaea, and viruses. This data provide the framework to adopt I. basta as a model organism for studying host-microbe interactions and provide a basis for in-depth physiological experiments.

Validation of key sponge symbiont pathways using genome-centric metatranscriptomics.

The sponge microbiome underpins host function through provision and recycling of essential nutrients in a nutrient poor environment. Genomic data suggest that carbohydrate degradation, carbon fixation, nitrogen metabolism, sulphur metabolism and supplementation of B-vitamins are central microbial functions. However, validation beyond the genomic potential of sponge symbiont pathways is rarely explored. To evaluate metagenomic predictions, we sequenced the metagenomes and metatranscriptomes of three common coral reef sponges: Ircinia ramosa, Ircinia microconulosa and Phyllospongia foliascens. Multiple carbohydrate active enzymes were expressed by Poribacteria, Bacteroidota and Cyanobacteria symbionts, suggesting these lineages have a central role in assimilating dissolved organic matter. Expression of entire pathways for carbon fixation and multiple sulphur compound transformations were observed in all sponges. Gene expression for anaerobic nitrogen metabolism (denitrification and nitrate reduction) were more common than aerobic metabolism (nitrification), where only the I. ramosa microbiome expressed the nitrification pathway. Finally, while expression of the biosynthetic pathways for B-vitamins was common, the expression of additional transporter genes was far more limited. Overall, we highlight consistencies and disparities between metagenomic and metatranscriptomic results when inferring microbial activity, while uncovering new microbial taxa that contribute to the health of their sponge host via nutrient exchange.

Increasing diversity in the genetic counseling profession: Development of recruitment tools for African American undergraduate students.

Lack of diversity in the genetic counseling profession has been a concern for over 20 years, with the National Society of Genetic Counselors identifying increasing diversity and inclusion as a strategic focus in 2019. Previous research has revealed potential barriers that could explain the low number of diverse applicants to genetic counseling graduate programs. The aims of this pilot study were to test strategies for participation and site recruitment methods for Historically Black Colleges and Universities (HBCUs) and to evaluate the effectiveness of a brief presentation tailored to African American students. Recruitment emails were sent to career services and 124 biology/psychology department chairs from HBCUs and one predominately white institution with over 10% black student population. There was a 16% response rate through career services and a 25% response rate from department chairs. Different sections of a single biology class at one HBCU were randomly assigned to either attend a class presentation by an African American second-year genetic counseling student and given a brochure detailing the same information (presentation group), or receive a brochure only (brochure group). Ninety students participated in the study: 65 in the presentation group and 25 in the brochure group. All students completed a 10-question knowledge test and were given an email address for further student-initiated contact about genetic counseling. In the presentation group, 65% (42/65) completed the knowledge test with a mean score of 7.59/10. Only one student from the brochure group completed the knowledge test. No students initiated contact to receive additional information about genetic counseling. This study highlights the difficulties in reaching African American students, even through HBCUs. Strategies beyond the use of brochures and presentations will be necessary to attract African American students into the genetic counseling profession.

Effects of Genetic Counselor Self-Disclosure: an Experimental Analog Study.

The complex nature of self-disclosure poses challenges for genetic counselors in clinical practice. We examined the impact of genetic counselor self-disclosure on observer perceptions of the counselor. In an online analog study, 123 participants watched a 3-minute video of a simulated genetic counseling session. For half the participants, the video showed the counselor disclosing that she had a family medical history similar to the patient (direct personal disclosure). For half the participants, the counselor revealed her experience with other patients (direct professional disclosure). Half the participants in each video condition read that the patient had discovered personal information about the counselor during a pre-session web search (indirect personal disclosure); half read that the patient learned of the counselor's FAQ webpage for prospective patients (indirect professional disclosure). Participants in the direct personal disclosure conditions gave higher ratings to the counseling relationship on an abbreviated version of the Barrett-Lennard Relationship Inventory and rated themselves more likely to see the counselor compared to those in the direct professional disclosure conditions. The content of the indirect disclosure conditions (personal or professional) had no effect. Brief, direct, verbal disclosure of session-relevant personal information by a genetic counselor appears to enhance the counselor-patient relationship and increase the likelihood of patients returning to the counselor.

Nonconscious priming enhances the therapy relationship: An experimental analog study.

OBJECTIVE: We examined whether nonconscious priming could enhance client perceptions of the therapist in an experimental analog study. METHOD: Sixty undergraduate participants each played the part of client in a brief scripted role-play of a therapy intake session. Sessions lasted about 3 min. The first author played the role of therapist. Participants were randomly assigned to view a line drawing depicting two individuals pointing either in the same direction (empathy prime) or opposite directions (non-empathy prime). The drawing appeared as a watermark on initial screening forms. The experimenter was blind to group assignment and participants received a cover story designed to mask the purpose of the primes. RESULTS: Participants in the empathy priming condition gave the therapist higher ratings of empathy and congruence, spoke to him longer, and rated their likelihood of future progress higher compared to participants in the non-empathy group. None of the participants expressed awareness of the priming manipulation during a funneled debriefing. CONCLUSIONS: These results demonstrate that client ratings of the therapy relationship can be experimentally manipulated without awareness and open the door to experimental studies of the association between relationship factors and treatment outcome.

A genome-centric view of the role of the Acropora kenti microbiome in coral health and resilience.

Microbial diversity has been extensively explored in reef-building corals. However, the functional roles of coral-associated microorganisms remain poorly elucidated. Here, we recover 191 bacterial and 10 archaeal metagenome-assembled genomes (MAGs) from the coral Acropora kenti (formerly A. tenuis) and adjacent seawater, to identify microbial functions and metabolic interactions within the holobiont. We show that 82 MAGs were specific to the A. kenti holobiont, including members of the Pseudomonadota, Bacteroidota, and Desulfobacterota. A. kenti-specific MAGs displayed significant differences in their genomic features and functional potential relative to seawater-specific MAGs, with a higher prevalence of genes involved in host immune system evasion, nitrogen and carbon fixation, and synthesis of five essential B-vitamins. We find a diversity of A. kenti-specific MAGs encode the biosynthesis of essential amino acids, such as tryptophan, histidine, and lysine, which cannot be de novo synthesised by the host or Symbiodiniaceae. Across a water quality gradient spanning 2° of latitude, A. kenti microbial community composition is correlated to increased temperature and dissolved inorganic nitrogen, with corresponding enrichment in molecular chaperones, nitrate reductases, and a heat-shock protein. We reveal mechanisms of A. kenti-microbiome-symbiosis on the Great Barrier Reef, highlighting the interactions underpinning the health of this keystone holobiont.

Microbes from Mum: symbiont transmission in the tropical reef sponge Ianthella basta.

Most marine sponge species harbour distinct communities of microorganisms which contribute to various aspects of their host's health and physiology. In addition to their key roles in nutrient transformations and chemical defence, these symbiotic microbes can shape sponge phenotype by mediating important developmental stages and influencing the environmental tolerance of the host. However, the characterisation of each microbial taxon throughout a sponge's life cycle remains challenging, with several sponge species hosting up to 3000 distinct microbial species. Ianthella basta, an abundant broadcast spawning species in the Indo-Pacific, is an emerging model for sponge symbiosis research as it harbours only three dominant symbionts: a Thaumarchaeotum, a Gammaproteobacterium, and an Alphaproteobacterium. Here, we successfully spawned Ianthella basta, characterised its mode of reproduction, and used 16S rRNA gene amplicon sequencing, fluorescence in situ hybridisation, and transmission electron microscopy to characterise the microbial community throughout its life cycle. We confirmed I. basta as being gonochoric and showed that the three dominant symbionts, which together make up >90% of the microbiome according to 16S rRNA gene abundance, are vertically transmitted from mother to offspring by a unique method involving encapsulation in the peri-oocytic space, suggesting an obligate relationship between these microbes and their host.

Characterization of a sponge microbiome using an integrative genome-centric approach.

Marine sponges often host diverse and species-specific communities of microorganisms that are critical for host health. Previous functional genomic investigations of the sponge microbiome have focused primarily on specific symbiont lineages, which frequently make up only a small fraction of the overall community. Here, we undertook genome-centric analysis of the symbiont community in the model species Ircinia ramosa and analyzed 259 unique, high-quality metagenome-assembled genomes (MAGs) that comprised 74% of the I. ramosa microbiome. Addition of these MAGs to genome trees containing all publicly available microbial sponge symbionts increased phylogenetic diversity by 32% within the archaea and 41% within the bacteria. Metabolic reconstruction of the MAGs showed extensive redundancy across taxa for pathways involved in carbon fixation, B-vitamin synthesis, taurine metabolism, sulfite oxidation, and most steps of nitrogen metabolism. Through the acquisition of all major taxa present within the I. ramosa microbiome, we were able to analyze the functional potential of a sponge-associated microbial community in unprecedented detail. Critical functions, such as carbon fixation, which had previously only been assigned to a restricted set of sponge-associated organisms, were actually spread across diverse symbiont taxa, whereas other essential pathways, such as ammonia oxidation, were confined to specific keystone taxa.

Synthesis and characterization of 2,7-di(tert-butyl)pyreno[4,5-c:9,10-c']difuran and derived pyrenophanes.

Isobenzofurans (IBF)s have seen widespread use in the synthesis of both natural products and polycyclic aromatic hydrocarbons. There are few examples that have two IBF entities linked in a fused aromatic ring system. Here we present the synthesis and characterization of a bis(IBF), 2,7-di(tert-butyl)pyreno[4,5-c:9,10-c']difuran. Reaction with bis(maleimide) dienophiles gives pyrenophanes. The solid-state structures of the bis(IBF) and two cyclophanes are discussed.

X-ray structures of cyclophanes derived from naphtho[1,2-c:5,6-c]difuran and the synthesis, structure, and reaction kinetics of its 1,3,6,8-tetrasilylated derivative.

A silylated derivative of naphtho[1,2-c:5,6-c]difuran, 1,3,6,8-tetrakis(tert-butyldimethylsilyl)naphtho[1,2-c:5,6-c]difuran, has been isolated and its X-ray crystal structure determined. Bond localization confirms the polyene character of this isobenzofuran ring system. This molecule undergoes two successive Diels-Alder reactions with second-order rate constants differing by over 2 orders of magnitude, consistent with predictions based on their structure-count ratios and with the reactivity of the novel 1,3-bis(tert-butyldimethylsilyl)isobenzofuran. Crystal structures of two cyclophanes derived from the reaction of naphtho[1,2-c:5,6-c]difuran and bis(imide) or bis(ester) dienophiles show marked differences in the conformation of the aliphatic chain found in the solid state.

A genomic view of the reef-building coral Porites lutea and its microbial symbionts.

Corals and the reef ecosystems that they support are in global decline due to increasing anthropogenic pressures such as climate change1. However, effective reef conservation strategies are hampered by a limited mechanistic understanding of coral biology and the functional roles of the diverse microbial communities that underpin coral health2,3. Here, we present an integrated genomic characterization of the coral species Porites lutea and its microbial partners. High-quality genomes were recovered from P. lutea, as well as a metagenome-assembled Cladocopium C15 (the dinoflagellate symbiont) and 52 bacterial and archaeal populations. Comparative genomic analysis revealed that many of the bacterial and archaeal genomes encode motifs that may be involved in maintaining association with the coral host and in supplying fixed carbon, B-vitamins and amino acids to their eukaryotic partners. Furthermore, mechanisms for ammonia, urea, nitrate, dimethylsulfoniopropionate and taurine transformation were identified that interlink members of the holobiont and may be important for nutrient acquisition and retention in oligotrophic waters. Our findings demonstrate the critical and diverse roles that microorganisms play within the coral holobiont and underscore the need to consider all of the components of the holobiont if we are to effectively inform reef conservation strategies.

(E)-1,2-Bis(3-bromo-4-methyl-phen-yl)ethene.

In the structure of the title compound, C(16)H(14)Br(2), the central C=C bond length is 1.329 (4) Šand the two benzene rings are approximately coplanar with the double bond, with twist angles of 7.5 (2) and 13.6 (2)°.

Effects of Ginkgo biloba administered after spatial learning on water maze and radial arm maze performance in young adult rats.

Ginkgo biloba is reported to improve learning and memory in animals. However, many studies do not directly test the effects of Ginkgo on memory because the drug is administered during the learning phase of the experiments. In this study, we examined the effect of 10 mg/kg, 20 mg/kg, or 40 mg/kg G. biloba extract on spatial memory by administering the drug in the interval between training and testing. Rats were tested for long-term reference memory retention in the radial arm maze and in the Morris water maze during daily probe trials in which the hidden platform was removed. G. biloba had no effect on reference memory in either the water maze or radial arm maze. To test short-term working spatial memory using the radial arm maze, animals were removed after receiving the reward from 4 of the 8 arms and were returned to complete the maze 2 h later. While Ginkgo had no effect on working memory, over time animals exposed to Ginkgo learned task better than control animals. Thus, Ginkgo appears to enhance neither short-term working memory nor long-term reference memory, but it may promote learning of spatial information.

Genome-Centric Analysis of Microbial Populations Enriched by Hydraulic Fracture Fluid Additives in a Coal Bed Methane Production Well.

Coal bed methane (CBM) is generated primarily through the microbial degradation of coal. Despite a limited understanding of the microorganisms responsible for this process, there is significant interest in developing methods to stimulate additional methane production from CBM wells. Physical techniques including hydraulic fracture stimulation are commonly applied to CBM wells, however the effects of specific additives contained in hydraulic fracture fluids on native CBM microbial communities are poorly understood. Here, metagenomic sequencing was applied to the formation waters of a hydraulically fractured and several non-fractured CBM production wells to determine the effect of this stimulation technique on the in-situ microbial community. The hydraulically fractured well was dominated by two microbial populations belonging to the class Phycisphaerae (within phylum Planctomycetes) and candidate phylum Aminicenantes. Populations from these phyla were absent or present at extremely low abundance in non-fractured CBM wells. Detailed metabolic reconstruction of near-complete genomes from these populations showed that their high relative abundance in the hydraulically fractured CBM well could be explained by the introduction of additional carbon sources, electron acceptors, and biocides contained in the hydraulic fracture fluid.

Methane metabolism in the archaeal phylum Bathyarchaeota revealed by genome-centric metagenomics.

Methanogenic and methanotrophic archaea play important roles in the global flux of methane. Culture-independent approaches are providing deeper insight into the diversity and evolution of methane-metabolizing microorganisms, but, until now, no compelling evidence has existed for methane metabolism in archaea outside the phylum Euryarchaeota. We performed metagenomic sequencing of a deep aquifer, recovering two near-complete genomes belonging to the archaeal phylum Bathyarchaeota (formerly known as the Miscellaneous Crenarchaeotal Group). These genomes contain divergent homologs of the genes necessary for methane metabolism, including those that encode the methyl-coenzyme M reductase (MCR) complex. Additional non-euryarchaeotal MCR-encoding genes identified in a range of environments suggest that unrecognized archaeal lineages may also contribute to global methane cycling. These findings indicate that methane metabolism arose before the last common ancestor of the Euryarchaeota and Bathyarchaeota.

The role of attentional bias in substance abuse.

There has been much recent interest in the idea that drug users show biased attention toward drug-related events. Because drug stimuli produce conditioned responses that may motivate drug taking, biased attention toward these cues may play an important role in drug use and relapse following treatment. The performance of drug users on the Stroop task and visual dot-probe task has been interpreted as demonstrating attentional bias toward drug cues specific to an individual's drug use history. However, studies often fail to include necessary control groups or comparison stimuli, thereby making it difficult to definitively conclude that reported results reflect a specific attentional response to personally relevant drug events. Although promising, these initial studies need to be followed up with better controlled demonstrations of attentional bias and with studies linking bias levels to other measures of drug taking.

Comparing attentional bias to smoking cues in current smokers, former smokers, and non-smokers using a dot-probe task.

Much evidence documents that individuals with emotional and drug-use disorders demonstrate biased attention toward stimuli associated with their disorder. This bias appears to diminish following successful treatment. Two studies examined whether current cigarette smokers show biased attention toward smoking-related images compared with non-smokers (Studies 1 and 2) and whether this bias is less pronounced in former smokers (Study 2). Attentional bias toward cigarette-related photographs was examined using the dot-probe task. Pairs of images (one smoking-related) appeared side by side for 500 ms on a computer screen prior to the presentation of a probe (an asterisk) replacing one of the photographs. Subjects struck a key as quickly as possible to indicate the probe location. Attentional bias was defined as faster reaction times when the probe replaced the smoking-related image. In both studies, current smokers displayed significantly greater attentional bias toward cigarette stimuli than did non-smokers. Former smokers in Study 2 displayed an intermediate level of bias, but did not differ significantly in bias score from either of the other groups. These results support further use of the dot-probe task as a measure of attentional bias in non-abstinent smokers and in individuals undergoing smoking cessation treatment.

A randomized, double-blind, placebo-controlled safety study of high-dose dextromethorphan in methadone-maintained male inpatients.

The NMDA antagonist dextromethorphan hydrobromide (DM) may be useful in the treatment of opioid dependence, particularly as a means of reducing tolerance to methadone during replacement therapy. As a prelude to clinical efficacy studies, a randomized, double-blind, placebo-controlled study examined the safety of DM in combination with methadone in inpatient, opiate-dependent volunteers. Male participants received daily methadone (50-70 mg/day) and either DM (n=10) or placebo (n=5) during the 12-day active medication phase of the study. DM participants received doses of 120, 240, and 480 mg/day in increasing order (4 days each). DM at high doses caused mild elevations of heart rate, blood pressure, temperature, and plasma bromide. However, none of these effects was clinically significant. DM caused no significant changes in respiration, pupil diameter, or subjective drug effects measured by standard scales. Participants in the DM group reported many more adverse events than did subjects on placebo (173 vs. 21), but these effects were not clinically serious. The most commonly reported side effects were sleepiness and drowsiness. Several participants reported intoxicating effects at the highest dose. Overall, DM was well-tolerated by the methadone-maintained opiate-dependent subjects studied here. These results support the further exploration of DM as an adjunct medication during methadone replacement therapy.

Ginkgo biloba promotes short-term retention of spatial memory in rats.

This study examines possible interactions between exposure to Ginkgo biloba extract and enriched environments on the acquisition and retention of spatial learning following massed and spaced trials. After 4 weeks of exposure to either ginkgo or vehicle, 8-week-old rats were tested using a Morris Water Maze in either massed or spaced trials. While ginkgo did not have an effect on maze acquisition or long-term retention, it did promote short-term retention of spatial memory. Following reversal training, ginkgo promoted short-term retention for two groups but impaired retention for a third. These results suggest that ginkgo has powerful effects on short-term retention that vary with training conditions.