Table of Contents

• Dataset Description
  • Methods & Sampling
  • Data Processing Description
• Data Files
• Parameters
• Instruments
• Deployments
• Project Information
• Funding

Data access is restricted. Please contact the PI for further information.

Related datasets:

Montipora antibacterial-mucus
Montipora antibacterial-organic
Montipora chemical fingerprints
MWS accession numbers
MWS lesion progression

Related references:

Deborah J. Gochfeld, Greta S. Aeby. 2008. Antibacterial chemical defenses in Hawaiian corals provide possible protection from disease. Mar Ecol Prog Ser 362: 119-128. doi: 10.3354/meps07418.

Preparation of extracts: Coral samples of orange and red colonies of Montipora capitata were collected in Kaneohe Bay, Oahu.  Frozen samples were extracted in Millipore® water, which was replaced daily for 3 d. Extracts were filtered, lyophilized, and weighed.  We tested extracts at concentrations approximating those naturally found in the coral tissues (Gochfeld & Aeby 2008). To determine the volumetric concentrations of extracts, the surface area of each piece of coral was calculated using the wax technique (Gochfeld 1991).  Tissue volume was determined by multiplying surface area by tissue depth measured from replicate decalcified pieces of M. capitata.  Extract concentrations were determined as g dried extract ml–1 of coral tissue.  Extracts were re-suspended to these concentrations in Millipore® water for use in bacterial growth assays.

Bacterial strains tested:  The strains used for our antibacterial assays were selected as model systems to represent a range of potential bacterial pathogens from the marine environment, including known coral pathogens (Aurantimonas coralicida, Serratia marcescens, Vibrio coraliilyticus, Vibrio shiloi) and human enteric bacteria that have the potential to enter near-shore waters and can survive in the marine environment (Yersinia enterocolitica), and strains previously isolated from the surfaces of Hawaiian corals (Klebsiella pneumonia, Vibrio agarivorans) (Gochfeld & Aeby 2008).  In addition, bacterial strains isolated from surfaces of Montipora capitata (OCN001, OCN002, OCN003, OCN008, O1-1, O2-8, O2-12, R1-13, R5-5, R5-13, R5-29) by Dr. Sean Callahan’s lab at University of Hawaii were also used.  Two of these, OCN002 and OCN008, are pathogens associated with Montipora White Syndrome (Ushijima et al. 2012, 2014).

Growth inhibition assay (Gochfeld & Aeby 2008):  Assays were run in triplicate in 96 well plates. Plates contained 3 wells of bacteria + each extract (n = 10 replicate corals of 2 color morphs), along with the following controls:  bacteria only, media only, and extract solution to control for the coloration of extracts.  Aqueous extracts were dissolved in Millipore® water.  Twenty-four hour bacterial cultures in exponential growth were diluted to optical density (OD) 600, and 100 μl were added to each well. 10 μl of extract were added to the experimental wells. Wells were mixed by carefully pipetting their contents, and an initial reading (time 0) of OD was made on a BioTek Synergy™ HT Multi-Detection Microplate Reader. Plates were then covered with foil and incubated on a shaker for 24 h and a final reading was made. Prior to each reading, wells were mixed again to resuspend any settled material.  

To compare the growth curves from assays performed on different plates and at different times, we controlled for natural bacterial growth in each assay by subtracting the mean optical density of the 3 control wells (media + bacteria) from the optical density of each well containing an extract in that assay.  In addition, the mean optical density of the 2 wells containing each extract solution was also subtracted from those wells to control for the dark color of the extracts.

BCO-DMO Processing:
added conventional header with dataset name, PI name, version date, reference information
renamed parameters to BCO-DMO standard
replaced blanks and / with underscores

Extracted from the NSF award abstract:

Diseases of marine organisms have emerged as a serious problem contributing to the decline of coral reef resources worldwide. Loss of coral reef habitats carry social and economic implications especially in island states, such as Hawaii, which depend on reefs for food, shoreline protection and tourism. Our ability to manage coral diseases is hampered by a lack of knowledge of which environmental variables affect disease, mechanisms of host defense, and the etiology of most of the numerous described coral diseases. The PIs of this project discovered a coral disease system that can be used as a model to explore many components of the host-environment-pathogen triangle of disease causation. Montipora white syndrome (MWS) is an infectious disease that results in progressive tissue loss on colonies of Montipora capitata, and has been found on reefs throughout the Hawaiian archipelago. It is particularly prevalent in Kaneohe Bay, Oahu, which has a long history of reduced water quality, and this suboptimal environment sets the stage where host-pathogen interactions occur. In Kaneohe Bay, M. capitata is a major reef-building species, and is found in two color morphs (red and orange) that harbor different clades of zooxanthellae. During preliminary surveys, the PIs discovered intraspecific variability in response to MWS between color morphs. Although the red morph was dominant within survey transects (80% of the colonies), the orange morph was disproportionately affected by MWS (70% of the affected colonies). Microbial studies found a shift in bacterial communities on MWS-affected and healthy M. capitata and allowed identification of potential pathogens. Numerous bacterial strains were cultured and screened for pathogenicity and three strains, which produced lesions, were identified as potential pathogens. Two of the putative pathogens (Vibrio spp.) produced diffuse tissue whereas the other bacterial strain (Pseudoalteromonas sp.) produced acute tissue loss.

In the field, the PIs also observed two patterns of tissue loss on M. capitata; a slow, chronic pattern of tissue loss, which they followed through time with tagged colonies (chronic MWS), but also a rapid onset of acute tissue loss (acute MWS). Thus they discovered an infectious coral disease that results in significant coral mortality that has the unique component of differences in disease susceptibility among color morphs. The PIs identified three potential bacterial pathogens that will be used to investigate underlying factors affecting the coral-environment-pathogen triad of disease causation. The Hawaii Institute of Marine Biology (HIMB) is located within Kaneohe Bay allowing year-round access to reefs for research on Montipora white syndrome. The goal of this project is to investigate the host- environment-pathogen triangle of disease causation for Montipora white syndrome. The objectives of this research will be to: 1) investigate mechanisms contributing to differential disease resistance in red (less susceptible) vs. orange (more susceptible) morphs of M. capitata. The PIs will compare antimicrobial activity in the holobiont, mucus and mucus-associated bacteria of the two color morphs of M. capitata, and will compare the natural coral-associated microbial flora between the two color morphs; 2) use manipulative aquarium studies to determine whether environmental stressors (elevated temperature, nutrient stress) differentially affect the progression or transmission efficiency of MWS in red vs. orange morphs of M. capitata; 3) use challenge experiments to confirm the role of bacterial pathogens as causative agents of MWS, and to determine the response of red vs. orange morphs of M. capitata to three putative pathogens. This project will involve a multidisciplinary team to provide a broader perspective of coral disease processes. This will be the first comprehensive study conducted on a coral disease in Hawaii.

Related Publications:

Ushijima, B, Videau, P, Burger, A, Shore-Maggio, A, Runyon, C, Sudek, M, Aeby, G and S. Callahan. 2014. Vibrio coralliilyticus strain OCN008 is an etiological agent of acute Montipora white syndrome. Applied & Environ Microbiology doi:10.1128/AEM.03463-13.

Ushijima B, Videau P, Aeby GS, Callahan SM. 2013. Draft Genome Sequence of Vibrio coralliilyticus Strain OCN008, Isolated from Kane'ohe Bay, Hawai'i. Genome Announc. 2013 Oct 3;1(5). doi:pii: e00786-13. 10.1128/genomeA.00786-13. PMID: 24092784

Ushijima B, Smith A, Aeby GS, Callahan SM (2012) Vibrio owensii Induces the Tissue Loss Disease Montipora White Syndrome in the Hawaiian Reef Coral Montipora capitata. PLoS ONE 7: e46717.