Marine Biology Commons^™

Reducing Host Dna Contamination In 16s Rrna Gene Surveys Of Anthozoan Microbiomes Using Pna Clamps, Alicia M. Reigel, Sarah M. Owens, Michael E. Hellberg

Faculty Publications

Efforts to study the microbial communities associated with corals can be limited by inefficiencies in the sequencing process due to high levels of host amplification by universal bacterial 16S rRNA gene primers. Here, we develop an inexpensive peptide nucleic acid (PNA) clamp that binds to a target sequence of host DNA during PCR and blocks amplification. We then test the ability of this PNA clamp to mitigate host contamination and increase overall microbial sequence coverage on samples from three coral species: the gorgoniansEunicea flexuosaandGorgonia ventalina,and the scleractinianPorites panamensis. The 20-bp PNA clamp was designed using DNA fromE. flexuosa. Adding the …

Quantifying Spatiotemporal Variability In Zooplankton Dynamics In The Gulf Of Mexico With A Physical-Biogeochemical Model, Taylor A. Shropshire, Steven L. Morey, Eric P. Chassignet, Alexandra Bozec, Victoria J. Coles, Michael R. Landry, Rasmus Swalethorp, Glenn Zapfe, Michael R. Stukel

Faculty Publications

© 2020. This work is distributed under the Creative Commons Attribution 4.0 License. Zooplankton play an important role in global biogeochemistry, and their secondary production supports valuable fisheries of the world's oceans. Currently, zooplankton standing stocks cannot be estimated using remote sensing techniques. Hence, coupled physical–biogeochemical models (PBMs) provide an important tool for studying zooplankton on regional and global scales. However, evaluating the accuracy of zooplankton biomass estimates from PBMs has been a major challenge due to sparse observations. In this study, we configure a PBM for the Gulf of Mexico (GoM) from 1993 to 2012 and validate the model …

Temporal And Stoichiometric Patterns Of Algal Stimulation Of Litter-Associated Heterotrophic Microbial Activity, Steven N. Francoeur, Robert K. Neely, Savannah Underwood, Kevin A. Kuehn

Faculty Publications

1. Periphyton communities associated with submerged plant detritus contain interacting autotrophic and heterotrophic microbes, and are sites of extracellular enzymatic activity. The strength and nature of these interactions might be expected to change over time as microbial communities develop on plant litter. Microbial interactions and enzymatic activity can be altered by nutrient availability, suggesting that litter stoichiometry could also affect these phenomena.
2. We grew wetland plants under ambient and nutrient‐enriched conditions to generate plant litter of differing nutrient content. In two experiments, we investigated: (1) the influence of algal photosynthesis on fungal and bacterial production and the activities of four extracellular …

Combined And Independent Effects On Hypoxia And Tributylin On Mrna Expression And Physiology Of The Eastern Oyster (Crassostrea Virginica), Ann Fairly Barnett, James H. Gledhill, Robert J. Griffitt, Marc Slattery, Deborah J. Gochfeld, Kristine L. Willett

Faculty Publications

Oyster reefs are vital to estuarine health, but they experience multiple stressors and globally declining populations. This study examined effects of hypoxia and tributyltin (TBT) on adult Eastern oysters (Crassostrea virginica) exposed either in the laboratory or the field following a natural hypoxic event. In the laboratory, oysters were exposed to either hypoxia followed by a recovery period, or to hypoxia combined with TBT. mRNA expression of HIF1-α and Tβ-4 along with hemocyte counts, biomarkers of hypoxic stress and immune health, respectively, were measured. In field-deployed oysters, HIF1-α and Tβ-4 expression increased, while no effect on hemocytes was …

Development And Characterization Of Genomic Resources For A Non-Model Marine Telost, The Red Snapper (Lutjanus Campechanus, Lutjanidae): Construction Of A High-Density Linkage Map, Anchoring Of Genome Contigs And Comparative Genomic Analysis, Adrienne E. Norrell, Kenneth L. Jones, Eric A. Saillant

Faculty Publications

The red snapper Lutjanus campechanus is an exploited reef fish of major economic importance in the Gulf of Mexico region. Studies of genome wide genetic variation are needed to understand the structure of wild populations and develop breeding programs for aquaculture but interpretation of these genome scans is limited by the absence of reference genome. In this work, the first draft of a reference genome was developed and characterized for the red snapper. P-454 and Illumina sequencing were conducted to produce paired-end reads that were assembled into reference contigs and scaffolds. The current assembly spans over 770 Mb, representing an …

Model Sensitivity To Topographic Uncertainty In Meso- And Microtidal Marshes, Karim Alizad, Stephen C. Medeiros, Madeline R. Foster-Martinez, Scott C. Hagen

Faculty Publications

Light detection and ranging (Lidar) derived digital elevation models are widely used in modeling coastal marsh systems. However, the topographic error in these models can affect simulations of marsh coverage and characteristics. We investigated the relevance and impact of this error in micro- and mesotidal systems. Lidar-derived and RTK-adjusted topography were each used in a dynamic marsh model, and the resulting marsh coverages were examined. For two microtidal sites (Apalachicola, FL, USA, and Grand Bay, MS, USA) using solely lidar-derived topography, the model produced Cohen Kappa values of 0.1 for both estuaries when compared with National Wetland Inventory data indicating …

Respiration By The Opportunistic Spionid Polychaete Streblospio Gynobranchiata During Adjustment To And Recovery From Moderate Hypoxia, Alyssa D. Bennett, Chet F. Rakocinski

Faculty Publications

Understanding the capacity of estuarine organisms to acclimate to stressful conditions provides insights into how communities cope within fluctuating environments. The opportunistic spionid polychaete, Streblospio gynobranchiata Rice and Levin, 1998, regularly experiences intermittent moderate hypoxia within shallow sedimentary habitats. To better understand fine-scale adjustments by this opportunistic species to short-term moderate hypoxia, the aerobic respiration response of three size classes was examined over a 12 h period and after 24 h of exposure to moderate hypoxia (i.e., 20% air saturation) at 25 °C. In addition, the capacity to resume standard respiration was examined over a 12 h period following a …

Exposure To Oil And Hypoxia Results In Alterations Of Immune Transcriptional Patterns In Developing Sheepshead Minnows (Cyprinodon Variegatus), Maria L. Rodgers, Danielle Simning, Maria S. Sepúlveda, Sylvain De Guise, Thijs Bosker, Robert J. Griffitt

Faculty Publications

The area and timing of the Deepwater Horizon oil spill highlight the need to study oil and hypoxia exposure in early life stage fishes. Though critical to health, little research has targeted the effect of oil and hypoxia exposure on developing immune systems. To this end, we exposed sheepshead minnows (Cyprinodon variegatus) at three early life stages: embryonic; post-hatch; and post-larval, to a high energy water accommodated fraction (HEWAF) of oil, hypoxia, or both for 48 hours. We performed RNAseq to understand how exposures alter expression of immune transcripts and pathways. Under control conditions, the embryonic to post-hatch …

Distribution, Relative Abundance, And Reproductive Output Of Spawning Female Blue Crab (Callinectes Sapidus) In Offshore Waters Of The Gulf Of Mexico, Adam A. Kemberling, M. Zachary Darnell

Faculty Publications

Effective assessment and management of migratory species require an understanding of stock boundaries and habitat use during critical life history periods. The blue crab (Callinectes sapidus) is considered a primarily estuarine species and has traditionally been assessed and man-aged on a state basis, relying on abundance estimates derived from estuarine sampling. Females undertake a sea-ward spawning migration, and recent evidence indicates that coastal and offshore waters may provide important spawning habitat. We investigated occurrence and reproductive output of spawning blue crab in offshore waters of the northwestern Gulf of Mexico, and results indicate that these waters may be …