2004 Progress Report: Characterization of Glycoprotein Cues Used by the Parasitic Rhizocephalan Barnacle Loxothylacus texanus To Identify Its Blue Crab Host, Callinectes sapidusEPA Grant Number: R830651C002
Subproject: this is subproject number 002 , established and managed by the Center Director under grant R827072
(EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
Center: Alabama Center For Estuarine Studies (ACES)
Center Director: Shipp, Robert L.
Title: Characterization of Glycoprotein Cues Used by the Parasitic Rhizocephalan Barnacle Loxothylacus texanus To Identify Its Blue Crab Host, Callinectes sapidus
Investigators: Boettcher, Anne , O'Brien, Jack , Sherman, Timothy
Institution: University of South Alabama
EPA Project Officer: Packard, Benjamin H
Project Period: August 1, 2003 through June 30, 2005
Project Period Covered by this Report: August 1, 2003 through June 30, 2004
RFA: Alabama Center For Estuarine Studies (ACES) (1999) RFA Text | Recipients Lists
Research Category: Targeted Research
The greater blue crab, Callinectes sapidus, is subject to infection by the parasitic rhizocephalan barnacle, Loxothylacus texanus. The cyprid larvae of L. texanus only settle on newly molted soft-shelled crabs that are less than 24 hours postmolt. Previous studies have indicated that the settlement cues used by L. texanus to identify its host are associated with carbohydrate moieties on the soft-shell of the host crab. The objective of this research project is to characterize changes in the glycoprotein profiles of postmolt crab shells during the hardening process (sclerotization and calcification). The secondary objective is to determine if the timing of the changes was dependent on the size of the crab. Understanding the settlement cues associated with this host/parasite interaction is an important step toward the development of tools to aid in the control of infection.
Initial studies focused on evaluation of appropriate tissue type for isolation of proteins from the crabs. Whole limb tissue was compared to limb tissue with the muscle excised. Results indicated that the presence of muscle tissue did not have a significant effect on protein profiles; however, the presence of the muscle tissue made protein extraction more difficult. Therefore, all future analyses were performed on tissue from which the muscle had been excised.
During Year 1 of the project, changes in the glycoprotein profile during the first 120 hours post ecdysis were examined. Comparison of protein banding patterns showed the most significant changes in the total protein profile occurred between 1 and 24 hours after ecdysis (Figures 1 and 2). The most dramatic changes in glycoprotein profiles also occurred within this timeframe (Figure 3).
Figure 1. 6 Day Time Series. Silver/Coomassie staining of low molecular weight proteins extracted from leg exoskeleton autotomized from C. sapidus (Lanes: [SMW] standard molecular weights, times postecdysis 1, 24, 48, 72, 96, and 120 hours)
Figure 2. 6 Day Time Series. Silver/Coomassie staining of high molecular weight proteins extracted from leg exoskeleton autotomized from C. sapidus (Lanes: [SMW] standard molecular weights, times postecdysis 1, 24, 48, 72, 96, and 120 hours)
Figure 3. 6 Day Time Series. Concanavalin A-probed mannose-rich high molecular weight proteins extracted from leg exoskeleton autotomized from C. sapidus (Lanes: [SMW] standard molecular weights, times postecdysis 1, 24, 48, 72, 96, and 120 hours)
This grant was used to fund the graduate research of Jason Herrmann. By the end of Year 1 of the project, Jason had completed his course work and teaching requirements, had his prospectus approved by his committee, and passed his comprehensive exam. As described above, the initial stages of his research also had been completed.
Subsequent studies will focus on the changes that occur over the first 24 hours post-ecdysis and on differences in the timing of responses based on size of the crab.
Journal Articles:No journal articles submitted with this report: View all 4 publications for this subproject
Supplemental Keywords:marine, estuary, ecology, gulf coast,
Progress and Final Reports:Original Abstract
Main Center Abstract and Reports:R827072 Alabama Center For Estuarine Studies (ACES)
Subprojects under this Center: (EPA does not fund or establish subprojects; EPA awards and manages the overall grant for this center).
R827072C001 Fluorescent Whitening Agents As Facile Pollution Markers In Shellfishing Waters
R827072C002 Red Snapper Demographics on Artificial Reefs: The Effect of Nearest-Neighbor Dynamics
R827072C003 Stabilization of Eroding Shorelines in Estuarine Wave Eliminates with Constructed Fringe Wetlands Incorporating Offshore Breakwaters
R827072C004 Interaction Between Water Column Structure and Reproduction in Jellyfish Populations Of Mobile Bay (SGER)
R827072C005 Effects of Variation in River Discharge and Wind-Driven Resuspension on Higher Trophic Levels in the Mobile Bay Ecosystem
R827072C006 Results of Zooplankton Component
R827072C007 Benthic Study Component
R827072C008 A Preliminary Survey of Macroalgal and Aquatic Plant Distribution in the Mobile Tensaw Delta
R827072C009 Fisheries-induced changes in the structure and function of shallow water "nursery habitats": an experimental assessment
R827072C010 Effects Of Variation in River Discharge and Wind-Driven Resuspension on Lower Trophic Levels of the Mobile Bay Ecosystem
R827072C011 Evaluation of Alabama Estuaries as Developmental Habitat for Juvenile Sea Turtles
R827072C012 Effects of Salinity Stress on Natural and Anthropogenically-Derived Bacteria in Estuarine Environments
R827072C013 The Role of Land-Use/Land-Cover and Sub-estuarine Ecosystem Nitrogen Cycling in the Regulation of Nitrogen Delivery to a River Dominated Estuary; Mobile Bay, Alabama
R827072C014 Environmental Attitudes of Alabama Coastal Residents: Public Opinion Polls and Environmental Policy
R827072C015 Synthesis and Characterization of an Electrochemical Peptide Nucleic Acid Probe
R827072C016 Determinants of Small-Scale Variation in the Abundance of the Blue Crab Callinectes Sapidus
R827072C017 Effects of Estrogen Pollution on the Reproductive Fitness of the Gulf Pipefish, Syngnathus scovelli
R827072C019 A Model for Genetic Diversity Aquatic Insects of the Mobile/Tensaw River Delta
R827072C020 Evaluating Trophic Processes as Indicators of Anthropogenic Eutrophication in Coastal Ecosystems: An Exploratory Analysis
R827072C021 Effects of Anthropogenic Eutrophication on the Magnitude and Trophic Fate of Microphytobenthic Production in Estuaries
R827072C022 Characteristics of Ship Waves and Wind Waves in Mobile Bay
R827072C023 Methods Comparison Between Stripping Voltammetry and Plasma Emission Spectroscopy for Metals in Mobile Bay
R827072C024 Changes in Water Conditions and Sedimentation Rates Associated With Construction of the Mobile Bay Causeway
R827072C025 Cold-Induced Hibernation of Marine Vibrios in the Gulf of Mexico: A Study of Cell-Cell Communication and Dormancy in Vibrio vulnificus
R827072C026 Holocene Sedimentary History of Weeks Bay, AL: Human and Natural Impacts on Deposition in a Gulf Coast Estuary
R827072C027 Shelter Bottlenecks and Self-Regulation in Blue Crab Populations: Assessing the Roles of Nursery Habitats and Juvenile Interactions for Shelter Dependent Organisms
R827072C028 Predicting Seagrass Survival in Nutrient Enriched Waters: Toward a New View of an Existing Paradigm
R827072C029 DMSP and its Role as an Antioxidant in the Salt Marsh Macrophyte Spartina alterniflora
R827072C030 A Preliminary Survey of Aerial and Ground-Dwelling Insects of the Mobile/Tensaw Delta
R827072C031 Natural Biogeochemical Tags of Striped Mullet, Mugil cephalus, Estuarine Nursery Areas in the North Central Gulf of Mexico
R827072C032 Resolution of Sedimentation Rates in Impacted Coastal Environments Using 137Cs and 210Pb Markers: Dog River and Fowl River Embayments
R827072C033 Investigation of the Use of Pulse Amplitude Modulated (PAM) Fluorometry as an Indicator of Submerged Aquatic Vegetation Health in Mobile Bay
R827072C034 Influence of Invasive Plant Species in Determining Diversity of Aquatic Vegetation in the Mobile-Tensaw Delta
R827072C035 The Influence of Shallow Water Hydrodynamics on the Importance of Seagrass Detritus in Estuarine Food Webs
R827072C036 Food Web Interactions, Spatial Subsidies and the Flow of Energy Between the Mobile Bay Delta and Offshore Waters: A SGER Proposal to the Alabama Center for Estuarine Studies
R830651C001 Meteorological Modeling of Hurricanes and Coastal Interactions: A Stability Study For Vertical Pressure Levels
R830651C002 Characterization of Glycoprotein Cues Used by the Parasitic Rhizocephalan Barnacle Loxothylacus texanus To Identify Its Blue Crab Host, Callinectes sapidus
R830651C003 Survey of Diamondback Terrapin Populations in Alabama Estuaries
R830651C004 An Assessment of Environmental Contaminant Levels in Water and Dragonfly Larvae Tissues from the Mobile/Tensaw Delta