Tag: scallop

Ayodeji defends his master’s thesis!

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Ayodeji Olaniyi defended his Master’s of Animal Science thesis today!! His project focused on cultures of bacteria that were isolated from the biofilms in scallop larvae hatchery tanks, to understand how they might be impacting larvae or microbial community dynamics in the tank. This was part of a series of studies and a larger collaboration on scallop health in Maine. He has previously presented at the 2024 NACE/MAS aquaculture conference for which he won a travel award from the UMaine Aquaculture research Insitute, and the 2023 UMaine Student Research Symposium where he won an award for his poster. He joined my lab in early 2022 to increase his technical research skills, and has been investigating the bacteria isolated from biofilms associated with different scallop hatchery tank systems.

He is originally from Nigeria, where he studied animal science and gathered a lot of practical experience in animal production and proper farm maintenance. He obtained a Bachelor of Science from Federal University of Agriculture in Abeokuta, Nigeria, and worked as a veterinary assistant and as a technical advisor at AlphaSage services, in Ibadan, Nigeria.

He has already begun the next phase of his career, as he started working as a research technician at a health lab in Indiana, where he has been combining his microbiology and animal health skills with molecular genetics, and adding to the list of animal systems he has worked with. And, his thirst for knowledge is still growing – we can’t wait to see where his passion for research takes him!

Scallop and microbes presentations at NACE/MAS meeting this week

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The Ishaq lab and some of our collaborators will be presenting out work on scallop health and microbes in hatcheries at the Northeast Aquaculture Conference & Exposition (NACE) and the 43rd Milford Aquaculture Seminar (MAS), which are being held together in Providence, Rhode Island this week on January 10-12.

Session: Scallop Health in Hatcheries

Chair: Sue Ishaq

Friday, 8:00 am in the Newport/Washington room

Sue Ishaq, Assistant Professor at UMaineBacterial community trends associated with sea scallop, Placopecten magellanicus, larvae in a hatchery system.
Ayodeji Olaniyi, Master’s student in the Ishaq Lab at UMaineInvestigating the activity of bacteria isolated from tank biofilms in a hatchery system for sea scallop, Placopecten magellanicus, larvae
Adwoa Dankwa, Postdoctoral research in the Perry Lab at UMaineIdentification of bacterial communities and their association with larval mortality in Atlantic sea scallops (Placopecten magellanicus) hatchery system
Kyle Brennan, Master’s student in the Bowden Lab at UMaineProbiotics and pathogens
Jaypee Samson, PhD Student in the Gomez-Chiarri Lab at URIIsolation, Screening, And Selection Of Potential Pathogenic And
Probiotic Bacteria From Bivalve Shellfishes
Sydney Avena, Master’s student at the Darling Marine Center“Cracking the shell”: Lessons learned from a collaborative approach to developing hatchery production of the Atlantic sea scallop, Placopecten magellanicus
Tara Riley, Shellfish and Aquatic Resources Manager for Nanucket, MASaving The Seed: Nantucket Bay Scallop Seed Management Of 2023
The speaker list for the session.

Session: Coastal Systems & Scallops

Chairs: Sue Ishaq and & Phoebe Jekielek

Friday, 1:30 pm in the Newport/Washington room

Samuel GurrDevelopmental mismatch of pCO 2 levels in a second generation of northern bay scallops
Christopher NorenComparing growth of ear hung and lantern net cultured sea scallops, Placopecten magellanicus, over a complete grow-out cycle to determine optimal harvest timing
Phoebe Jekielek A comparative study of sea scallop (Placopecten magellanicus) energy investment strategies in farmed and wild environments
Caitlin CleaverUnderstanding wild sea scallop (Placopecten magellanicus) larval spatial and temporal distribution in Maine to support culture and capture fisheries
Paul RawsonPredicting larval dispersal and population connectivity of Sea Scallops, Placopecten magellanicus, in Downeast Maine.
Griffin HarkinsReview of Nantucket Island’s Bay Scallop Spat Bag Program
Speakers for the session
Ay and Sue at NACE
Kyle Brennan
Sydney Avena
Ayodeji Olaniyi

The first look at Atlantic deep sea scallop bacterial communities in new publication

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Our paper was published in Aquaculture Reports, on identifying the bacteria associated with wild and hatchery-raised Atlantic sea scallop larvae, and the biofilms in larval tanks in a hatchery! For the past few years, I’ve been part of a state-wide collaboration between researchers, industry professionals, and educators all working together to understand and improve Atlantic sea scallop hatchery production. To our knowledge, this is the first study to identify bacteria in Atlantic sea scallops, and even though it was a very small project we hope it will lead to a much larger, mult-year project to investigate this in more detail.

Sarah Hosler presentating a slide of questions about the microbes that associate with scallops
Sarah Hosler, ASM 2022.

Scallops are a diverse animal group of marine bivalve mollusks (family Pectinidae) with global distribution in coastal waters, and Atlantic deep-sea scallops, Placopecten magellanicus, are found along the eastern coast of the United States and Canada. Scallops’ reproductive potential and industry demand make them a prime target for hatchery- and farm-based production, and this has been successfully achieved in bay scallops, but not in sea scallops. Currently, hatcheries collect wild sea scallop adults, or maintain cultured broodstocks, and spawn them in their facilities with the intention of forming a plentiful population to grow to adulthood, spawn, and sell to create a sustainable production cycle while also reducing disruption to the scallops’ natural habitat.

Unfortunately, in sea scallop hatcheries the last two weeks of the larval maturation phase, the veliger-stage, is plagued by large mortality events, going from 60 million sea scallop larvae down to several thousand individuals in a span of 48 hours. Survival of clutches to maturity remains very low, with an industry-standard rate around 1%. This drastic winnowing of larvae reduces the availability of cultured sea scallop spat for farmers, forcing sea scallop farms to rely almost exclusively on sea scallop spat collected from wild populations for stock and is seen as a bottleneck for growth of the industry and achieving sustainable harvests. Hatchery larval die-off is well-demonstrated not to be caused by inadequate diet, lighting, temperature, or atmospheric pressure in aquaculture facilities compared to wild conditions.

This project wanted to know if there was any clue in the bacteria that associate with larvae, or with the tanks they are in. In particular, hactcheries are worried about certain species of bacteria in the genus Vibrio, as they can cause disease to scallops and/or people, but it is tricky to study them because there are many species which do nothing at all. This project is part of another experiment to examine some of the Vibrio we found in tanks.

We sampled from some wild larvae, hatchery larvae, and from tank biofilms to indentify what was there. There were two styles of tank setup, and we collected from used tanks as well as tanks after they had been cleaned and refilled with filtered seawater.

Veliger-stage Atlantic sea scallop larvae (Placopecten magellanicus) were obtained from hatchery tanks in Beals, Maine and from the wild off the coast of Cape Elizabeth, Maine. Swabs of hatchery tank biofilms were collected before and after tank cleaning. Bacterial communities were identified using DNA extraction and 16S rDNA sequencing on wild veligers, hatchery veligers and biofilm swabs. Image created with biorender.

One of the surprising things we found, was that the bacterial communities in biofilms along the sides of larvae tank were more similar to each other (clustering) when samples were collected during the same phase of the lunar cycle. Bacterial richness and community similarity between tank samples fluctuated over the trial in repeated patterns of rise and fall, which showed some correlation to lunar cycle  where richness is high when the moon is about 50% and richness is low during new and full moon phases. This may be a proxy for the effects of spring tides and trends in seawater bacteria and phages which are propagated into hatchery tanks. The number of days since the full moon was significantly correlated with bacterial community richness in tanks: low during the full moon, peaking ~ 21 days after the full moon, and decreasing again at the next full moon.  

Fig. 7. Constrained ordination of bacterial communities in tank samples. Each point represents the bacterial community from one sample. Similarity between samples was calculated using Distance-based Redundancy Analysis (dbDRA), and significant model factors (anova, p < 0.01) are displayed with arrow lengths relative to their importance in the model (f value). The shape of points indicates whether swabbing was either immediately after filtered seawater has been used to fill the tank (cleaned, refilled) or 48 hours after (dirty, drained). Tank setup indicates if water was static, constantly filtered and recirculated in a flow-through system, or setup information was not available (n/a).

These results along with future work, will inform hatcheries on methods that will increase larval survival in these facilities, for example, implementing additional filtering or avoiding seawater collection during spring tides, to reduce certain bacterial taxa of concern or promoting a more diverse microbial community which would compete against pathogens.

Bacterial community trends associated with sea scallop, Placopecten magellanicus, larvae in a hatchery system.

Authors: Suzanne L. Ishaq1*, Sarah Hosler1, Adwoa Dankwa1, Phoebe Jekielek2, Damian C. Brady3, Erin Grey4,5, Hannah Haskell6, Rachel Lasley-Rasher6, Kyle Pepperman7, Jennifer Perry1, Brian Beal8, Timothy J. Bowden1

Affiliations:1 School of Food & Agriculture, University of Maine, Orono ME 044692 Ecology and Environmental Sciences, University of Maine, Orono ME 044733 School of Marine Sciences, Darling Marine Center, University of Maine, Walpole ME 045734 School of Biology and Ecology, University of Maine, Orono ME 044695 Maine Center for Genetics in the Environment, University of Maine, Orono ME 044696 Department of Biological Sciences, University of Southern Maine, Portland ME 041037 Downeast Institute, Beals, ME 046118 Division of Environmental & Biological Sciences, University of Maine at Machias, Machias, ME 04654

Abstract

Atlantic sea scallops, Placopecten magellanicus, are the most economically important marine bivalves along the northeastern coast of North America. Wild harvest landings generate hundreds of millions of dollars, and wild-caught adults and juvenile spat are increasingly being cultured in aquaculture facilities and coastal farms. However, the last two weeks of the larval maturation phase in hatcheries are often plagued by large mortality events. Research into other scallop- and aquacultured-species point to bacterial infections or altered functionality of microbial communities which associate with the host. Despite intense filtering and sterilization of seawater, and changing tank water every 48 hours, harmful microbes can still persist in biofilms and mortality is still high. There are no previous studies of the bacterial communities associated with the biofilms growing in scallop hatchery tanks, nor studies with wild or hatchery sea scallops. We characterized the bacterial communities in veliger-stage wild or hatchery larvae, and tank biofilms using the 16S rDNA gene V3-V4 region sequenced on the Illumina MiSeq platform. Hatchery larvae had lower bacterial richness (number of bacteria taxa present) than the wild larvae and tank biofilms, and hatchery larvae had a similar bacterial community (which taxa were present) to both wild larvae and tank biofilms. Bacterial richness and community similarity between tank samples fluctuated over the trial in repeated patterns of rise and fall, which showed some correlation to lunar cycle that may be a proxy for the effects of spring tides and trends in seawater bacteria and phages which are propagated into hatchery tanks. These results along with future work, will inform hatcheries on methods that will increase larval survival in these facilities, for example, implementing additional filtering or avoiding seawater collection during spring tides, to reduce bacterial taxa of concern or promote a more diverse microbial community which would compete against pathogens.

Acknowledgements

The authors would like to thank the staff at the Downeast Institute for supporting the development and implementation of this project, as well as for financially supporting the DNA sequencing; Meredith White of Mook Sea Farm for sharing her expertise and collecting biofilm samples; the Darling Marine Center for sharing their expertise and collecting biofilm samples; and the Sea Scallop Hatchery Implementation (Hit) Team for their expertise, review of this work, and funding support, who are financially supported by the Atlantic States Marine Fisheries Commission and Michael & Alison Bonney. The authors thank Lilian Nowak for assistance with related lab work to this project, and the Map Top Scholars Program for related financial support. The authors also thank Nate Perry for helping us collect wild scallop larvae. All authors have read and approved the final manuscript. This project was supported by the USDA National Institute of Food and Agriculture through the Maine Agricultural & Forest Experiment Station, Hatch Project Numbers: ME0-22102 (Ishaq), ME0-22309 (Bowden), and ME0-21915 (Perry); as well through NSF #OIA-1849227 to Maine EPSCoR at the University of Maine (Grey). This project was supported by an Integrated Research and Extension Grant from the Maine Food and Agriculture Center, with funding from the Maine Economic Improvement Fund.

Upcoming presentations at the 2023 Ecological Society of America annual meeting!

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Ecological Society of America meeting, Aug 6 – 11, 2023, Portland, Oregon

Scallop microbes and sustainable aquaculture: host-microbe dynamics situated in environmental and social context.

Presentation ID: 1372900

Session Information

Session Title: Microbes as Tools to Solve Ecological Problems for All
Session Type: Inspire Session
Date: Thursday August 10, 2023
Session Time: 3:30 PM – 5:00 PM Pacific Time

Authors: Suzanne L. Ishaq1

Affiliations: 1 University of Maine, School of Food and Agriculture, Orono, ME 04469 USA

Atlantic sea scallop (Placopecten magellanicus) is the second largest fishery in Maine, primarily through wild harvest. Farming is a promising way to meet year-round market demands, create jobs, and reduce ecological impacts of harvest, but relies on wild-caught juveniles as larval survival in hatcheries is low for unknown reasons. My collaborative research group explores the role of larval and tank microbiomes in hatcheries compared to wild scallop veligers. In addition to basic and applied microbiome research, the research team meets with industry partners weekly to discuss results, trends, generate real-world-problem-driven project designs, and collaborate on research, education, and student training.

Bacterial community trends associated with sea scallop, Placopecten magellanicus, larvae in a hatchery system.

Poster ID:  1475974
Poster Title: “Bacterial community trends associated with sea scallop, Placopecten magellanicus, larvae in a hatchery system.”

Session Information

Agriculture
Session Date: Tuesday August 8, 2023 
Session Time: 5:00 PM – 6:30 PM Pacific Time

Authors: Suzanne L. Ishaq1*, Sarah Hosler1, Adwoa Dankwa1, Damian C. Brady2, Erin Grey3, Phoebe Jekielek4, Kyle Pepperman5, Jennifer Perry1, Rachel Lasley-Rasher6, Brian Beal3,7, Timothy J. Bowden1

Affiliations: 1 School of Food & Agriculture, University of Maine, Orono ME 04469. 2 School of Marine Sciences, Darling Marine Center, University of Maine. 3 School of Biology and Ecology, University of Maine, Orono ME 04469. 4 Department of Biological Sciences, University of Southern Maine, Portland ME 04103. 5 Downeast Institute, Beals, ME 04611. 6  Ecology and Environmental Sciences, University of Maine, Orono ME 04473. 7 Division of Environmental & Biological Sciences, University of Maine at Machias, Machias, ME 04654

Atlantic sea scallops, Placopecten magellanicus, are the most economically important marine bivalves along the northeastern coast of North America, and wild-caught adults and juvenile spat are increasingly being cultured in aquaculture facilities and coastal farms. While adults can be induced to spawn successfully in hatcheries, the last two weeks of the larval maturation phase are plagued by large mortality events, making production unfeasible. Research into other scallop- and aquacultured-species point to animal loss from bacterial infections or from altered functionality of host-associated microbiota. There are no previous studies of the bacterial communities from biofilms growing in scallop hatchery tanks, nor even host-microbial studies with this species of sea scallops. We identified bacterial communities in veliger-stage wild larvae, hatchery larvae, and tank biofilms, using the V3-V4 region of the 16S rDNA gene, via Illumina MiSeq sequencing. Hatchery larvae had lower bacterial richness (number of bacteria taxa present) than the wild larvae and tank biofilms, and hatchery larvae had a similar bacterial community (which taxa were present) to both wild larvae and tank biofilms. Bacterial richness was not significantly different between tanks which had been occupied by larvae for 48 hours, and those which had just been drained, scrubbed clean, and refilled with filtered seawater. Static-water-flow compared to continuous-water-flow (flow-through) did not generate different levels of bacterial richness overall, and only an equivocal difference when accounting for time as a smoothing feature in the model (GAM, p = 0.04). Bacterial richness and community similarity between tank samples fluctuated over the trial in repeated patterns of rise and fall, which showed some correlation to lunar cycle  where richness is high when the moon is about 50% and richness is low during new and full moon phases. This may be a proxy for the effects of spring tides and trends in seawater bacteria and phages which are propagated into hatchery tanks. The number of days since the full moon was significantly correlated with bacterial community richness in tanks (GAM, p < 0.01): low during the full moon, peaking ~ 21 days after the full moon, and decreasing again at the next full moon.  These results along with future work, will inform hatcheries on methods that will increase larval survival in these facilities, for example, implementing additional filtering or avoiding seawater collection during spring tides, to reduce certain bacterial taxa of concern or promoting a more diverse microbial community which would compete against pathogens.

Upcoming presentations at the American Society for Nutrition conference

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The Ishaq Lab will be presenting at a few research conferences this summer, with a few more in the works for the fall.

Broccoli sprouts in a tray

American Society for Nutrition meeting, July 22-25, 2023, Boston, Massachusetts

Steamed broccoli sprouts alleviate gut inflammation and retain gut microbiota against DSS-induced dysbiosis.

Poster, abstract P20-022-23, July 23

Authors: Johanna M. Holman*1, Lola Holcomb2, Louisa Colucci3, Dorien Baudewyns4, Joe Balkan5, Grace Chen6, Peter L. Moses7,8, Gary M. Mawe7, Tao Zhang9, Yanyan Li1, Suzanne L. Ishaq1

Affiliations: 1 School of Food and Agriculture, University of Maine, 2 Graduate School of Biomedical Sciences and Engineering, University of Maine, 3 Department of Biology, Husson University, 5 Department of Chemical and Biological Engineering, Tufts University, 6 Department of Internal Medicine, University of Michigan Medical School, 7 Departments of Neurological Sciences and of Medicine, Larner College of Medicine, University of Vermont, 8 Finch Therapeutics, 9 School of Pharmacy and Pharmaceutical Sciences, SUNY Binghamton University.

Objectives: Inflammatory Bowel Diseases (IBD) are devastating conditions of the gastrointestinal tract with limited treatments, and dietary intervention may be effective, affordable, and safe for managing symptoms. Ongoing research has identified inactive compounds in broccoli sprouts, like glucoraphanin, and that mammalian gut microbiota play a role in metabolizing it to the anti-inflammatory sulforaphane. The objectives were to identify biogeographic location of participating microbiota and correlate that to health outcomes. 

Methods: We fed specific pathogen free C57BL/6 mice either a control diet or a 10% steamed broccoli sprout diet, and gave a three-cycle regimen of 2.5% dextran sodium sulfate (DSS) in drinking water over a 40-day experiment to simulate chronic, relapsing ulcerative colitis. We monitored body weight, fecal characteristics, fecal lipocalin, and sequenced bacterial communities from the contents and mucosa in the jejunum, cecum, and colon. 

Results: Mice fed the broccoli sprout diet while receiving DSS performed better than mice fed the control diet while receiving DSS for all disease parameters, including significantly more weight gain (2-way ANOVA, p < 0.05), lower Disease Activity Index scores (2-way ANOVA, p < 0.001), and higher bacterial richness in all gut locations (linear regression model, p < 0.01 for all locations measured). Bacterial communities were assorted by gut location except in the mice receiving the control diet and DSS treatment (Beta-diversity, ANOVA, p < 0.05 for each). Importantly, our results suggested that broccoli sprout feeding completely abrogated the effects of DSS on gut microbiota, as bacterial communities were similar between mice receiving broccoli sprouts with and without DSS. 

Conclusions: Spatially resolved microbial communities provide greater insight when investigating host-microbe interactions. Here, we show that a 10% broccoli sprout diet protects mice from the negative effects of dextran sodium sulfate induced colitis, that colitis erases biogeographical patterns of bacterial communities in the gut, and that the cecum is not likely to be a significant contributor to colonic bacteria of interest in the DSS mouse model of ulcerative colitis. 

Funding Sources: This work was funded by the NIH, USDA, NSF NRT, and UMaine GSBSE.

 

Early life exposure to broccoli sprouts confers stronger protection against enterocolitis development in an immunological mouse model of inflammatory bowel disease.

Poster, abstract P20-021-23, July 23

Authors: Lola Holcomb*1, Johanna Holman2, Molly Hurd3, Brigitte Lavoie3, Louisa Colucci4, Gary M. Mawe3, Peter L. Moses3,5, Emma Perry6, Allesandra Stratigakis7, Tao Zhang7, Grace Chen8, Suzanne L. Ishaq1, Yanyan Li1

1 Graduate School of Biomedical Sciences and Engineering, University of Maine, 2 School of Food and Agriculture, University of Maine, 3 Larner College of Medicine, University of Vermont, 4 Department of Biology, Husson University, 5 Finch Therapeutics, 6 Electron Microscopy Laboratory, University of Maine, 7 School of Pharmacy and Pharmaceutical Sciences, SUNY Binghamton University, 8 Department of Internal Medicine, University of Michigan Medical School.

Objectives: Inflammatory Bowel Diseases (IBD) are chronic conditions characterized by inflammation of the gastrointestinal (GI) tract that burden daily life, result in complications, and disrupt the gut microbiome. Many studies on diet and IBD in mice use an ulcerative colitis model, despite the availability of an immune-modulated Crohn’s Disease model. The objective of this study was to establish IL-10 deficient mice as a model for studying the role of dietary broccoli and broccoli bioactives in reducing inflammation, modifying the immune response, and supporting GI tract microbial systems. 

Methods: Interleukin-10-knockout (IL-10-ko) mice on a C57BL/6 background, beginning at age 4 or 7 weeks, were fed either a control diet or one containing 10% raw broccoli sprouts. Diets began 7 days prior to inoculation with Helicobacter hepaticus, which triggers Crohn’s-like symptoms in these immune-impaired mice, and ran for 2 additional weeks. 

Results: Broccoli sprouts decreased (p < 0.05), fecal lipocalin (LCN2), a biomarker for intestinal inflammation, and fecal blood, diarrhea, and overall Disease Activity Index. Sprouts increased gut microbiota richness, especially in younger mice (p < 0.004), and recruited different communities in the gut (B-diversity, ANOVA, p < 0.001), especially in the colon (B-diversity, ANOVA, p = 0.03). The control group had greater prevalence and abundance of otherwise commensal bacteria which trigger inflammation in the IL-10-ko mice. Helicobacter was within the top-5 most prevalent core genera for the control group, but was not within the top-5 for the broccoli group. Disease parameters and microbiota changes were more significant in younger mice receiving broccoli.

Conclusions : A diet containing 10% raw broccoli sprouts may be protective against negative disease characteristics of Helicobacter-induced enterocolitis in IL-10-ko mice, and younger age is the most significant factor (relative to diet and anatomical location) in driving gut bacterial community richness and similarity. The broccoli diet contributes to prevalence and abundance of bacterial genera that potentially metabolize dietary compounds to anti-inflammatory metabolites in the gut, are bacteriostatic against pathogens, and may ease disease severity.

Funding Sources: This work was funded by the NIH, USDA, NSF NRT, and UMaine GSBSE.

Establishing Growth Curve Assays for Bacterial Glucosinolate Metabolism: A Study Protocol

Poster, abstract P22-030-23, July 23

Marissa Kinney*1, Ryan Wijayanayake1, Johanna Holman1, Timothy Hunt2, Benjamin Hunt 2, Tao Zhang3, Grace Chen4, Yanyan Li1 , Suzanne L. Ishaq1

1School of Food and Agriculture, University of Maine, Orono, Maine, USA 04469; 2 School of Biology and Ecology, University of Maine, Orono, Maine, USA 04469; 3 School of Pharmacy and Pharmaceutical Sciences, SUNY Binghamton University, Johnson City, New York, USA 13790; 4 Department of Internal Medicine, University of Michigan Medical School, Ann Arbor, Michigan, USA 48109 

Objective: Inflammatory bowel diseases (IBD) cause dysfunction of the gastrointestinal (GI) tract and can result in hospitalization, suffering and disruption to overall health. Recent work has demonstrated the anti-inflammatory capacity of a broccoli sprout-diet in artificially-induced GI inflammation in pathogen free C57BL/6 mice. Microbiota samples obtained from the GI tract of these mice will be used to study the presence and activity of broccoli glucosinolate hydrolysis to create microbial-sourced bioactives, to further understand the relationship between broccoli-diets and inflammation reduction. It is imperative to validate or replicate qPCR protocols which have been established for glucosinolate metabolism in Bacteroides thetaiotaomicron (B. theta), in other bacterial species. Additionally, this project will focus on developing new growth curve assays for glucosinolate metabolism, as these methods are lacking in published literature. 

Methods: Pathogen free C57BL/6 mice were given dextran sodium sulfate (DSS) into their drinking water to create a disease profile similar in development and morphology to human ulcerative colitis (UC), a type of IBD. DSS and a steamed broccoli sprout diet were administered. Samples were taken from the digesta, jejunum, cecum, and colon of mice fed broccoli diets. About 806 bacterial isolates will be grown up/cultured anaerobically on minimal/selective media containing glucosinolate-related compounds (glucoraphanin, sinigrin) to determine hydrolysis activity via spectroscopy to measure optical density of growth in competent isolates. Successful isolates will be further analyzed with LC/MS to confirm production of bioactive products, and with qPCR using the B. theta positive control genome to help identify gene targets (α-1,6-mannanase, glycosyl hydrolase, nicotinamide-dependent oxidoreductase, and transcriptional regulator protein) for glucosinolate conversion in isolates. 

Results  N/A

Conclusions: In the initial study from which these samples are sourced, mice fed a broccoli diet had less inflammation than those fed a control diet and DSS, and had higher bacterial diversity in their gut. We expect that bacteria isolated from the GI of broccoli-fed mice will contain more glucosinolate-metabolizing genes.

Funding: NIH (Li and Ishaq) and USDA (Li). 

Broadening Perspectives by Situating Nutrition Education in Broader Social Contexts: A Study Protocol

Poster, abstract number 1490287, July 23

Authors: Ashley Toney*1, Patricia Wolf*2, Sue Ishaq*3

Affiliations: 1Dept. of Cardiovascular and Metabolic Sciences, Cleveland Clinic Lerner Research Institute, 2 Department of Nutrition Science, Purdue University, 3 School of Food and Agriculture, University of Maine

Objectives: The Microbes and Social Equity (MSE) Working Group connects microbiology with social equity research, education, policy, and practice to understand the interplay of microorganisms, individuals, societies, and ecosystems. Given the complexity and nuance of evidence-based nutrition delivery, MSE sought to provide a conceptual structure. The goals are 1) convene diverse researchers, educators, learners, and practitioners, 2) publish and present evidence-based information within socio-cultural contexts, and 3) teach audiences to define ways for integrating equity into their work.

Methods: MSE hosted a 14-week speaker series in 2021, 2022, and 2023, with researchers from various disciplines (e.g., nutrition, gut microbes, food security). The series lead into a 5-day symposium of speakers and guided discussions to generate co-written documents identifying research needs and resources. We use targeted and non-targeted event promotion to attract audiences, and reach/impact is evaluated through registration, attendance, social media views, or attendee feedback. The series provides learning sessions that build concepts over time, guiding attendees past the conceptual roadblock of being new to interdisciplinary research and grappling with grand challenges. This extended period to learn stimulates participation in activity-based collaboration during symposia, even from new members or students. 2023 symposium attendees will be surveyed on their impressions on the event, how it impacted their perspective on experimental design, whether attendees started with the series and followed up with the symposium, and whether having the preface of the series aided in being able to create actionable outputs in a guided co-working session.

Results: n/a

Conclusions: Benefits include nuanced knowledge/perspective sharing, establishing and nurturing interdisciplinary collaboration, and sparking conversations on critical topics in policy, sustainability, host and microbial metabolism, etc. In the last 3 years, MSE published 4 papers together, with ~ 50 independent papers from members. Event recordings are used as curriculum in nutrition, microbiology, and pre-med biology.

Funding Sources: NIH/NIDDK, Allen Foundation (Ishaq); National Dairy Council (Toney)

Catch of the day: lots and lots of microbiology

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Over the past few months, a large team of undergraduate, graduate, and postdoctoral researchers, and I, have been processing hundreds of samples from our scallop hatchery microbiome project. As 2022 winds down, so does the first phase of our lab work, and we are taking a well-deserved break over the holidays before we launch additional lab work, data analysis, and manuscript writing in 2023.

In 2021, the Ishaq Lab, collaborators at UMaine, and collaborators at the Downeast Institute ran a pilot project to investigate the bacteria that associate with sea scallop larvae in hatcheries, and how this is develops in relation to bacteria in hatchery tanks over time. For that project, we collected hundreds of culture plates with a specialized media that selects for certain species of bacteria.

When tanks are drained and cleaned every two days, cotton swabs are rolled across part of the bottom or side of the tank and used to inoculate bacteria onto these culture plates. This is part of a routine screening for pathogens, and don’t worry, we aren’t finding bacteria that causes disease in humans. But, these screening plates creates a useful starting point for our research on bacterial community dynamics.

Tank swab samples are used to inoculate TCBS plates to screen for Vibrio and similar bacteria

We received over 200 of these TCBS culture plates, and from them we isolated 140 bacteria in 2021 and early 2022 which we archived at -80 degrees Celsius. This was part of Sarah Hosler’s master’s of science thesis in August of 2022, and has since been passed to Ayodeji Olaniyi for part of his master’s of science thesis.

This fall, we were able to recover 115 of these isolates from the deep freeze, and tested them on 12 different media in duplicate, which created >1800 cultures plates and tubes, and 230 microscope slides!

This massive undertaking would not have been possible without a large team helping with the lab work, including rockstars Ayodeji Olaniyi, Sydney Shair, Keagan Rice, and Lacy Mayo who put in hours and hours leading the efforts on this. We are also grateful to Alaa Rabee, Aaron Williams, Lily Robbins, Ash VanNorwick, and Rebecca Kreeger who provided assistance with media making, inoculating, and the large amount of cleanup (we used glass or autoclavable plastic where possible, and sterilized some single-use plastics to be used as training tools for student education). We were also assisted by Bryanna Dube, who is working on creating outreach/education materials based on our results.

Now, our team will focus on analyzing the results of all these microbiology tests and look for trends. Some will also be heading to the Perry Lab to learn how to perform quantitative polymerase chain reactions (qPCR), in which we use a modified version of DNA replication to count the copies of specific genes. We will use this to look for genes which confirm the identity of our bacteria.

Beginning in summer 2022, the Ishaq Lab has also been part of a state-wide research and commercial collaboration to understand and improve sea scallop production in hatcheries and farms. As part of that project, we received 1500 DNA samples from different hatchery tanks or larvae over the summer/fall rearing season.

Gloria Adjapong is a Postdoctoral Fellow at the UMaine Cooperative Extension Veterinary Diagnostics Lab, and she has been graciously extracting these samples as part of her cross-training in the Ishaq Lab. We will use the extracted DNA to sequence the bacterial communities to identify which bacteria are present, and when, to understand microbial community dynamics over time and in relation to scallop health.

Sarah defends her master’s thesis defense!

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Sarah Hosler passed her Master’s of Science these defense (we knew she would succeed)!! Sarah has worked incredibly hard over the last two years to broaden her research skills and conduct four completely different pilot projects. Her defense presentation focused on the two main projects, but was a wonderful way to see that progression all at once and to reflect on her growth as a lab manager and researcher. She has also earned the designation of “second Ishaq Lab grad student to defend”.

The defense was attended by her thesis committee, students in the Ishaq lab, collaborators on this project, friends and family, and Izzy the dog (pictured, and yes, Sarah preferred this picture of her at her defense to a portrait of herself. Sarah will officially pass after a few revisions to her thesis and a formal acceptance by the committee members, which is standard for graduate defenses.

After wrapping up a few things in Maine, Sarah will be heading to Pennsylvania to take a position as Student Program Coordinator for middle and high school aged students at Albright College, where she obtained her Bachelor’s of Science. Congrats on the defense and on the next stage of your career!

“Weaving An Interdisciplinary Microbiome Career Using Threads From Different Ecosystems”.

Sarah sets a date for her master’s thesis defense!

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Weaving an interdisciplinary microbiome career using threads from different ecosystems.

Presented by Sarah Hosler in fulfillment of her Master’s of Science in Animal Science degree at the University of Maine. Jul 27, 2022 12:00 – 14:00 PM Eastern Time (US and Canada)

Register in advance to attend this presentation over Zoom, which will also be held in person in 206 Rogers Hall at the University of Maine (no RSVP required). After registering, you will receive a confirmation email containing information about joining the meeting.

A graduate student and a faculty member, both in full graduation regalia, posing for a photo in a gymnasium.

About Sarah

Sarah officially joined my lab and started as a Master’s of Animal Science student at UMaine in fall 2020, which was during an extremely tumultuous time in history, and was only a year into my Assistant Professor position here at UMaine and before the lab had built up protocols, collaborations, samples, or momentum. Collectively, this meant that Sarah was part of my work to establish a laboratory and has been blazing that trail along with me. As such, in addition to the technical and analytical skills she has been learning, she has obtained a massive amount of professional development and leadership experience.

Sarah’s research interests are the interaction between the microbial community associated with various animal species, animal health or productivity, and the environment. This work is highly interdisciplinary, and requires extensive imagination and forethought into experimental designs which can capture biological, microbiological, and environmental data. This research theory is directly in line with the One Health in the Environment research group at UMaine, as well as the Microbes and Social Equity working group – an international research collaboration which I lead-, both of which Sarah has obtained mentorship from. This graduate work has focused on developing pilot studies and new research collaborations for three major projects/lines of scientific inquiry.

The first project centered around the tracking of Cryptosporidium parvum in different-aged dairy cattle populations as well as their pens at the University of Maine’s J.F. Witter Farm. Cryptosporidium is a small protozoan; a single-celled organism, and it is found in and around water and soil, as it spends most of its life cycle in those places. Humans and animals may ingest it through contaminated water or the fecal-oral route accidentally. In very young (such as calves) or immunocompromised individuals, an infection can occur, causing diarrhea and dehydration, and leading to death in many cases. Sarah has trained multiple undergraduates on sample collection and processing, as well as cell staining and microscopy, and the project has already collected dozens of samples. As this project will proceed for at least two years, it is not the main focus of Sarah’s thesis, however she will be an author on the eventual publication and she is leading a review manuscript on cryptosporidiosis which we will submit for peer review by fall 2022.

The second project investigated pathogens in wild rodent populations in Maine, in the context of heat stress and northward-shorting range changes due to climate changes. A pilot project collected biological data and samples from live-trapped flying squirrels and white-footed mice in six locations across Maine over summer 2021. The pilot project involved three additional investigators with complementary expertise, as well as their associated student mentees. To investigate disease potential, free catch fecal samples were collected from trapped animals to identify carriage of specific pathogens, and to isolate bacteria and assess heat tolerance. Sarah coordinated the training of undergraduate students in my and other labs, including sample collection and processing, microbial culture, DNA extraction, and more.

The third project project, and primary focus of her second year, investigated the microbial communities associated with sea scallops at different life stages and associated with tank surfaces at different points in a hatchery production run. Overall, there is a dramatic lack of research into the microbial communities involved in aquaculture and fisheries and how these might impact production as well as local ecosystems. Sarah processed a large number of samples for DNA extraction and sequencing preparation, as well as microbial culturing and biofilm assessment, and trained an undergraduate on the culturing work. This project and the piloting work Sarah did has led to a small grant award and a multiple-institutional collaboration. Sarah presented some of this preliminary work to aquaculture and fisheries industry professionals at the Northeast Aquaculture Conference & Exposition/ 41st Milford Aquaculture Seminar in Portland, and the American Society for Microbiology Microbe meetings. Sarah is currently writing this manuscript which will be submitted for peer review by the end of this summer.

This graduate work was highly collaborative, and required a great deal of professionalism.  Each of the three research projects that Sarah had been working on involves a primary team of faculty or animal science professionals, most of whom are on campus at UMaine but some of whom are remote at external institutions. Each of the three projects also involved 1 – 4 undergraduate students participating in the research.  Not only did Sarah help me organize project team meetings, and facilitate those meetings, but she coordinated data collection and file management for those projects, as well as trained and oversaw undergraduates in the laboratory. These skills are so often overlooked in research training, and are often considered part of the background in science. However, as tenure-track faculty, I would argue that these organization and research coordination skills are the most valuable for advancing complicated projects.

Pilot project funded to study Vibrio bacteria in scallop farming

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A collaborative pilot project was funded by the Maine Food and Agriculture Center (MFAC) to investigate Vibrio bacteria in scallop hatcheries in Maine! This will support some ongoing work by a collaborative research team at UMaine and the Downeast Institute, as we develop a long-term, larger-scale project investigating scallop health and survival in hatcheries, something which will be critical to supporting sustainable and economically viable aquaculture productions.

“Investigating microbial biofilms in Maine hatchery production of sea scallop, Placopecten magellanicus.”

Principal Investigator: Sue Ishaq

Co-Investigators:

  • Dr. Tim Bowden, Associate Professor of Aquaculture, University of Maine
  • Dr. Jennifer Perry, Assistant Professor of Food Microbiology, University of Maine
  • Dr. Brian Beal, Professor of Marine Ecology, University of Maine at Machias; and Research Director/Professor, Downeast Institute
  • Dr. Erin Grey, Assistant Professor of Aquatic Genetics, University of Maine

Project Summary: Atlantic deep-sea scallops, Placopecten magellanicus, are an economically important species, generating up to $9 million in Maine alone. Despite their potential to the aquaculture industry, hatchery-based sea scallop production cannot rely on the generation of larvae to produce animals for harvest. In hatcheries, the last two weeks of the larval maturation phase is plagued by massive animal death, going from 60 million scallop larvae down to a handful of individuals in a span of 48 hours. This forces farmed scallop productions to rely on collection of wild scallop spat (juveniles), but wild population crashes, habitat quality, harvesting intensity, and warmer water temperatures threaten the sustainability and economic viability of this industry. The reasons for sea scallop larvae death remain unknown, but other cultured scallop species are known to suffer animal loss from bacterial infections, including from several bacterial species of  Vibrio and Aeromonas. At the Downeast Institute in Beals, Maine, biofilms appear on tank surfaces within 24 hours. Routine screening for the presence of Vibrio sp. in tanks at DEI reveals no obvious signs of colonies in scallop tanks. Preliminary culturing and genetic identification from these biofilms suggests a species of Pseudoalteromonas, known biofilm formers which outcompete or inhibit other microorganisms. Our goal is to investigate the dynamics of tank surface biofilms in bivalve aquaculture facilities. Our long-term goals are to understand microbial community assembly and animal health during scallop hatchery production, and to standardize management practices to enhance the success of cultured scallop production.  

Experimental design schematic for this project. Our objectives are to 1) Identify the microbial community members involved in tank biofilms, and if it is a repeated or novel community assembly, and 2) Test for biofilm antagonism in vitro, using competing microorganisms, chemical treatments, and environmental conditions.