Previous Article | Next Article 
Applied and Environmental Microbiology, February 2008, p. 883-888, Vol. 74, No. 3
0099-2240/08/$08.00+0 doi:10.1128/AEM.01124-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.
Identification of a Ciliate (Oligohymenophorea: Scuticociliatia) Associated with Brown Band Disease on Corals of the Great Barrier Reef
David G. Bourne,1*
Holly V. Boyett,1,2
Meegan E. Henderson,3
Andrew Muirhead,1 and
Bette L. Willis2
Australian Institute of Marine Science, PMB No. 3, Townsville, MC, QLD 4810, Australia,1
ARC Centre of Excellence for Coral Reef Studies and School of Marine and Tropical Biology, James Cook University, Townsville, QLD 4811, Australia,2
Centre for Marine Studies, University of Queensland, Brisbane, Australia3
Received 20 May 2007/
Accepted 29 November 2007

ABSTRACT
A ciliate associated with the coral disease brown band (BrB)
was identified as a new species belonging to the class Oligohymenophorea,
subclass Scuticociliatia. The ciliates were characterized by
the presence of large numbers of intracellular dinoflagellates
and displayed an elongated, tube-shaped body structure. They
had uniform ciliature, except for three distinct cilia in the
caudal region, and were typically 200 to 400 µm in length
and 20 to 50 µm in width.

INTRODUCTION
Coral reef ecosystems have been exposed to increasing levels
of sedimentation, nutrient enrichment, and ocean warming in
the past few decades (
1,
20-
22), resulting in corals experiencing
elevated levels of stress and enhanced susceptibility to disease
infection (
9,
19,
20,
23,
31). Coral disease epizootics have
become a major threat to reef ecosystems globally, with reports
of newly emerging syndromes continuing to increase in numbers
(
17,
41). Identifying the microbial communities associated with
coral diseases is critical to further current understanding
of how environmental and climate changes might affect the prevalence
of diseases. To date, a wide range of microorganisms, including
fungi, bacteria, and cyanobacteria, have been identified in
association with both healthy and diseased corals (
10,
14,
18,
29,
30,
32,
33,
44), although microbial communities associated
with many coral diseases remain unknown (
41).
Seven coral diseases on the Great Barrier Reef (GBR) have been described previously (42), although their causative agents remain largely undescribed. One disease, named brown band (BrB), was described for the first time in studies of corals in three families (Acroporidae, Pocilloporidae, and Faviidae) in the northern and southern sectors of the GBR (42). Macroscopic symptoms of the disease manifest as a brown zone, which is preceded by healthy tissue and followed by exposed white skeleton as it progresses across the coral (see Fig. 1a). In some cases, a white zone, comprising bleached tissue and/or denuded skeleton, is observed between the brown band and healthy tissue. The distinctive brown color that constitutes the macroscopic field signs of BrB is derived from a mass of unknown ciliates gliding over the exterior surface of coral samples and into the coelenteron and cavities of the coral polyps. Here we report the identification of the ciliate associated with BrB by use of microscopic and molecular approaches.
Ciliates were removed from specimens of the staghorn coral (
Acropora muricata) exhibiting signs of BrB. Disease samples were collected
from Davies Reef (
n = 3) located in the central sector of the
GBR (18°49.86'S, 147°38.2'E) and from fringing reefs
around Heron Island (
n = 1) located in the southern sector of
the GBR (23°44.17'S, 151°91.25'E). All samples were
taken from near the advancing front of the disease lesion and
encompassed the brown band ciliate mass. Although potentially
a complex microbial community involving bacteria, diatoms, dinoflagellates,
and other microscopic marine plankton, the ciliate population
appeared uniform and dominated by one morphologically distinct
protozoan (Fig.
1b). Ciliates removed from coral specimens were
processed for microscopic analysis by fixation in Bouin's solution
(
13,
15) and stored in the dark at 4°C or kept at –80°C
until DNA was extracted.
High densities of intracellular zooxanthellae (Symbiodinium sp.) were observed within all ciliates examined by use of light microscopy (Fig. 1c). Morphologically, the ciliate had an elongated, tube-like shape rounded at both the posterior and apical ends (Fig. 1c). The length of the ciliate ranged from 200 to 400 µm, while the width ranged from 20 to 50 µm. Ciliation was uniform over the surface of the organism (Fig. 1c) except for three distinct and extended cilia in the caudal region. Scanning electron microscopy (SEM) revealed the oral apparatus to be differentiated from somatic ciliature and located in the buccal cavity on the ventral side (Fig. 1d).
Total DNA from ciliate and coral tissue samples (extracted according to the methods described in references 6 and 43) was amplified with conserved eukaryotic primers (18S-6-CIL-V and 18S-1511-CIL-R) (15). PCR resulted in amplification of the 18S rRNA genes from protozoa and other eukaryotic organisms (by PCR cycling performed at 95°C for 3 min followed by 30 cycles at 95°C for 1 min, 58°C for 1 min, and 72°C for 1 min and a final extension step of 72°C for 7 min), with the products (
1.8 kb) cloned (TOPO TA cloning kit; Invitrogen) and the insert 18S rRNA gene reamplified from individual clones. Restriction fragment length polymorphism analysis was performed on reamplified products (8), and clones were grouped into operational taxonomic unit (OTU) groups. Clones sequenced from the dominant OTU groups were affiliated with Symbiodinium species within the clade C lineage (98% to 99% sequence identity). One OTU group was affiliated with 18S rRNA gene sequences of ciliates within the scuticociliate family and was putatively identified as derived from the dominant BrB ciliate organism. This sequence demonstrated 95% sequence identity (over 1,749 bp) to the 18S rRNA gene sequence of the Parauronema longum ciliate. Phylogenetic comparisons indicated that the unknown ciliate is related to other ciliates belonging to the class Oligohymenophorea, subclass Scuticociliatia (Fig. 2). This subclass includes the scuticociliates Schizocaryum dogieli, Cohnilembus verminua, Anophyroides haemophila, Pseudocohnilembus marinus, and Uronema marinum. Scuticociliates often feed on bacteria, using complex morphological adaptations to create currents and filters capable of capturing bacteria and other particles from the water column or scraping them from hard surfaces (25).
Based on the retrieved 18S rRNA gene sequence, new PCR primers
were designed using the oligonucleotide primer algorithm of
the ARB package (
27). Generated primers were checked against
the GenBank database by a standard nucleotide-nucleotide BLAST
search (
3). PCR primers specific for the identified BrB ciliate
included BrB-F-171 and BrB-R-1721 (Table
1) (PCR cycling was
performed at 95°C for 3 min followed by 35 cycles at 95°C
for 30 s, 45°C for 45 s, and 72°C for 2 min, with a
final extension of 72°C for 10 min). Further BrB tissue
samples from both Davies Reef and Heron Island were amplified
and clones screened as described previously. Sequencing of the
dominant clone types retrieved almost identical ciliate-affiliated
18S rRNA gene sequences (>98% sequence identity) as obtained
with the eukaryotic-specific primer set.
Two oligonucleotide probes, BrB-754 and BrB-1461, targeted to
variable regions of the BrB ciliate 18S rRNA sequence, were
designed using the probe design algorithm of the ARB package
(
27) and checked against the GenBank database (
3). Alignment
and comparison of closely related 18S rRNA sequences demonstrated
mismatches for both probes (Fig.
3). Fixed ciliate samples (
15)
were filtered onto 0.22-µm-pore-size white Isopore membrane
filters (Millipore) by use of a gentle vacuum and washed five
times with 1 ml of filtered sterile seawater. Membranes were
covered with hybridization buffer (0.9 M NaCl, 20 mM Tris-HCl
[pH 8], 0.01% sodium dodecyl sulfate, 30% [vol/vol] formamide)
and the appropriate fluorochrome-labeled oligonucleotide probe
(50 µg). All hybridizations were conducted at 46°C
for 3 h, after which membranes were floated into prewarmed wash
buffer (0.102 M NaCl, 20 mM Tris-HCl [pH 8], 0.01% sodium dodecyl
sulfate, 5 mM EDTA) at 48°C for 10 min to remove excess
and nonbound oligonucleotide probes. Air-dried filters were
mounted in an antifading gel (Biomedia, ProSciTech) before being
viewed and imaged on a Bio-Rad MRC-1024 confocal laser scanning
microscope (
40).
Hybridizations with the eukaryote-specific probe EUK1195 (
16)
resulted in the presence of a fluorescence signal for both the
ciliate and the internalized
Symbiodinium sp. (Fig.
4a). Comparative
hybridizations of the BrB tissue with probes BrB-754 and BrB-1461
resulted in a fluorescent signal for the ciliate, correlating
the retrieved 18S rRNA gene sequence with the distinct morphological
characteristics of the BrB ciliate (Fig.
4b and c). Morphological
features of the ciliates could also be distinguished, including
the buccal cavity on the ventral side (Fig.
4b). No signal associated
with
Symbiodinium sp. was observed for the BrB ciliate-targeted
probes, supporting probe specificity. Signals from the EUK1195,
BrB-754, and BrB-1461 probes were clearly distinguishable from
autofluorescence signals achieved with negative-control hybridizations
(NONEUB nonsense probe) (
4) (Fig.
4d).
Ciliates belonging to the Scuticociliatia subclass are abundant
in marine habitats and often observed as endosymbionts in marine
invertebrates such as echinoids, crustaceans, polychaetes, and
bivalve mollusks (
25). Although the feeding behavior of the
brown band ciliate requires further study, the high density
of
Symbiodinium cells observed within its membranes (Fig.
1c)
is the primary cause of the brown color that characterizes the
disease's appearance in the field (Fig.
1a). At present, it
is unknown whether the ciliate ingests zooxanthellae in the
course of feeding on live coral tissue (i.e., is carnivorous),
ingests zooxanthellae in the course of feeding on dead coral
tissue (histophagous), or acquires them from elsewhere (algivorous).
However, the presence of high densities of feeding ciliates,
in combination with the retrieval of
Symbiodinium 18S rRNA gene
sequences from DNA extracted from ciliate samples that match
the clade C lineage, previously shown to be the dominant type
associated with
Acropora muricata at our sampling locations
(
39), suggests that members of the
Symbiodinium are derived
from coral tissue. Hence, the ciliates are likely to be either
carnivorous or histophagous. Recent studies demonstrated that
the internalized
Symbiodinium zooxanthellae remain photosythetically
competent within the ciliate, allowing the protozoan to gain
additional energy from photosynthates and alleviate potential
oxygen limitations due to high population densities and respiration
demands in the brown band zone (
38). Such a mixotrophic strategy
is common among freshwater oligotrichs, with enslaved photosynthetic
components remaining functional for hours to days, thereby providing
nutrients, covering respiratory demands, and increasing growth
efficiency (
11,
34-
36). Whether a similar relationship exists
between BrB ciliates and internalized
Symbiodinium zooxanthellae
has yet to be determined; however, symbiotic relationships between
ciliates and zooxanthellae have previously been reported for
ciliates living in association with corals (
26).
Although common in marine environments, ciliates are rarely classified as pathogenic parasites (28), especially in coral communities. One study has linked a GBR coral disease with the Halofolliculina corallasia heterotrich ciliate. Known as skeletal eroding band, this disease has been characterized by an advancing mass of ciliates whose pericytostomial wings are encased within flask-like black loricae (5). Protozoan infections have also been identified on corals held in aquaria. For example, the consumption of coral tissue by the ciliate Helicostoma nonatum produces brown jelly-like symptoms in infected aquarium corals (7). Willis et al. (42) speculated that the ciliate associated with BrB might be related to H. nonatum, although results from this study suggest that it belongs to a different family. Other studies have identified a protozoan belonging to the phylum Apicomplexa within microbial communities associated with the coral Montastraea annularis in the Caribbean, but although this protozoan is related to a group of highly parasitic organisms, whether or not it is parasitic on corals is currently unknown (37).
The causative agent of the coral disease BrB remains unknown. The appearance of a white bleached zone, often observed between healthy coral tissue and an advancing mass of ciliates (Fig. 1a), suggests that the ciliate may invade secondarily after coral health is compromised, although it is clear that the ciliate subsequently becomes responsible for macroscopic field signs of BrB disease. A number of factors may compromise coral health, including bacterial or viral infections, injury, and, alternatively, apoptosis triggered by stress, injury, or infection (2, 18). As the health of the coral deteriorates, necrosing tissue could attract the ciliate to feed on both bacteria and zooxanthellae associated with dead and dying coral tissue. At high densities, however, the ciliates may become the primary cause of tissue loss as they uptake photocompetent zooxanthellae to alleviate potential oxygen limitations (38).
In summary, the characteristic macroscopic signs of the coral disease BrB have been attributed to the presence of a newly identified ciliate species of the class Oligohymenophorea, subclass Scuticociliatia. Future studies investigating the life cycle and taxonomic traits of the ciliate are required along with additional microbiological studies to further clarify the nature of the causative agent(s) of this coral disease.

Nucleotide sequence accession number.
The nucleotide sequence data have been submitted to the GenBank
nucleotide sequence database under accession number AY876050.

ACKNOWLEDGMENTS
We thank Neal Cantin, Meir Sussman, and Cathie Page from James
Cook University for field and laboratory assistance, Kevin Blake
from James Cook University for help in generating SEM images,
and Neil Young, Lone Høj, Eric Matson, and Jason Doyle
from the Australian Institute of Marine Science and Colin Munn
from the University of Plymouth for their assistance in field
and laboratory studies.
Research was supported by an ARC DP grant to B. L. Willis and the Coral Disease Working Group of the GEF CRTR Program.

FOOTNOTES
* Corresponding author. Mailing address: Australian Institute of Marine Science, PMB No. 3, Townsville, MC, QLD 4810, Australia. Phone: 61 7 4753 4139. Fax: 61 7 47725852. E-mail:
d.bourne{at}aims.gov.au 
Published ahead of print on 14 December 2007. 

REFERENCES
1 - Acosta, A. 2001. Disease in zoanthids: dynamics in space and time. Hydrobiologia 460:113-130.[CrossRef]
2 - Ainsworth, T. D., E. C. Kvennefors, L. L. Blackall, M. Fine, and O. Hoegh-Gulberg. 2006. Disease and cell death in white syndrome of acroporid corals on the Great Barrier Reef. Mar. Biol. 151:19-29.
3 - Altschul, S. F., T. L. Madden, A. A. Schaeffer, J. Zhang, Z. Zhang, W. Miller, and D. J. Lipman. 1997. Gapped BLAST and PSI-BLAST: a new generation of protein database search programs. Nucleic Acids Res. 25:3389-3402.[Abstract/Free Full Text]
4 - Amann, R. I., L. Krumholz, and D. A. Stahl. 1990. Fluorescent-oligonucleotide probing of whole cells for determinative, phylogenetic, and environmental studies in microbiology. J. Bacteriol. 172:762-770.[Abstract/Free Full Text]
5 - Antonius, A., and D. Lipscomb. 2001. First protozoan coral-killer identified in the Indo-Pacific. Atoll Res. Bull. 493:1-21.
6 - Asahida, T., T. Kobayashi, K. Saitoh, and I. Nakayama. 1996. Tissue preservation and total DNA extraction from fish stored at ambient temperature using buffers containing high concentrations of urea. Fish. Sci. 62:727-730.
7 - Borneman, E. H. 2001. Aquarium corals: selection husbandry and natural history. TFH Publications, Neptune City, NJ.
8 - Bourne, D. G., and C. B. Munn. 2005. Diversity of bacteria associated with the coral Pocillopora damicornis from the Great Barrier Reef. Environ. Microbiol. 7:1162-1174.[CrossRef][Medline]
9 - Bruno, J. F., E. R. Selig, K. S. Casey, C. A. Page, B. L. Willis, C. D. Harvell, H. Sweatman, and A. M. Melendy. 2007. Thermal stress and coral cover as drivers of coral disease outbreaks. PLoS Biol. 5:1-7.[CrossRef]
10 - Cooney, R. P., O. Pantos, M. D. A. Le Tissier, M. R. Barer, A. G. O'Donnell, and J. C. Bythell. 2002. Characterisation of the bacterial consortium associated with the black band disease in coral using molecular microbiological techniques. Environ. Microbiol. 4:401-413.[CrossRef][Medline]
11 - Dolan, J. R., and M. T. Pérez. 2000. Costs, benefits and characteristics of mixotrophy in marine oligotrichs. Freshw. Biol. 45:227-238.[CrossRef]
12 - Felsenstein, J. 1989. PHYLIP—phylogeny inference package (version 3.2). Cladistics 5:164-166.
13 - Foissner, W. 1991. Basic light and scanning electron microscopic methods for taxonomic studies of ciliated protozoa. Eur. J. Protistol. 27:313-330.
14 - Frias-Lopez, J., A. L. Zerkle, G. T. Bonheyo, and B. W. Fouke. 2002. Partitioning of bacterial communities between seawater and healthy, black band diseased, and dead coral surfaces. Appl. Environ. Microbiol. 68:2214-2228.[Abstract/Free Full Text]
15 - Fried, J., W. Ludwig, R. Psenner, and K. H. Schleifer. 2002. Improvement of ciliate identification and quantification: a new protocol for fluorescence in situ hybridisation (FISH) in combination with silver stain techniques. Syst. Appl. Microbiol. 25:555-571.[CrossRef][Medline]
16 - Giovannoni, S. J., E. F. DeLong, G. J. Oslen, and N. R. Pace. 1988. Phylogenetic group-specific oligonucleotide probes for identification of single microbial cells. J. Bacteriol. 170:720-726.[Abstract/Free Full Text]
17 - Green, E., and A. Bruckner. 2000. The significance of coral disease epizootiology for coral reef conservation. Biol. Conserv. 96:347-361.[CrossRef]
18 - Harvell, C. D., E. Jordan-Dahlgren, S. Merkel, E. Rosenberg, L. Raymundo, G. Smith, E. Weil, and B. L. Willis. 2007. Coral disease, environmental drivers and the balance between coral and microbial associates. Oceanography 20:58-81.
19 - Harvell, C. D., K. Kim, J. Burkholder, R. Colwell, P. Epstein, D. Grimes, E. Hofmann, E. Lipp, A. Osterhaus, R. Overstreet, J. Porter, G. Smith, and G. Vasta. 1999. Emerging marine diseases—climate links and anthropogenic factors. Science 285:1505-1510.[Abstract/Free Full Text]
20 - Harvell, C. D., C. E. Mitchell, J. R. Ward, S. Altizer, A. P. Dobson, R. S. Ostfeld, and M. D. Samuel. 2002. Climate warming and disease risks for terrestrial and marine biota. Science 296:2158-2162.[Abstract/Free Full Text]
21 - Hoegh-Guldberg, O. 1999. Climate change, coral bleaching and the future of the world's coral reefs. Mar. Freshw. Res. 50:839-866.[CrossRef]
22 - Hughes, T. P., A. H. Baird, D. R. Bellwood, M. Card, S. R. Connolly, C. Folke, R. Grosberg, O. Hoegh-Guldberg, J. B. C. Jackson, J. Kleypas, J. M. Lough, P. Marshall, M. Nystrom, S. R. Palumbi, J. M. Pandolfi, B. Rosen, and J. Roughgarden. 2003. Climate change, human impacts and the resilience of coral reefs. Science 301:929-933.[Abstract/Free Full Text]
23 - Lafferty, K. D., J. Porter, and S. E. Ford. 2004. Are diseases increasing in the oceans? Annu. Rev. Ecol. Evol. Syst. 35:31-54.[CrossRef]
24 - Lane, D. J. 1991. 16S/23S rRNA sequencing, p. 115-175. In E. Stackebrandt and M. Goodfellow (ed.), Nucleic acid techniques in bacterial systematics. John Wiley and Sons, New York, NY.
25 - Lee, J. J., and G. M. Capriulo. 1990. The ecology of marine protozoa: an overview, p. 1-15. In G. M. Capriulo (ed.), Ecology of marine protozoa. Oxford University Press, New York, NY.
26 - Lobban, C. S., M. Schefter, A. G. B. Simpson, X. Pochon, J. Pawlowski, and W. Foissner. 2002. Maristentor dinoferus n. gen., n. sp., a giant heterotrich ciliate (Spirotrichea: Heterotrichida) with zooxanthellae, from coral reefs on Guam, Mariana Islands. Mar. Biol. 141:207-208.[CrossRef]
27 - Ludwig, W., O. Strunk, R. Westram, L. Richter, H. Meier, Yadhukumar, A. Buchner, T. Lai, S. Steppi, G. Jobb, W. Förster, I. Brettske, S. Gerber, A. W. Ginhart, O. Gross, S. Grumann, S. Hermann, R. Jost, A. König, T. Liss, R. Lüβmann, M. May, B. Nonhoff, B. Reichel, R. Strehlow, A. Stamatakis, N. Struckmann, A. Vilbig, M. Lenke, T. Ludwig, A. Bode, and K.-H. Schleifer. 2004. ARB: a software package environment for sequence data. Nucleic Acids Res. 32:1363-1371.[Abstract/Free Full Text]
28 - Lynn, D. H., and J. O. Corliss. 1991. Ciliophora, p. 333-467. In F. W. Harrison (ed.), Microscopic anatomy of invertebrates, vol. 1: protozoa. Wiley-Liss, Inc., New York, NY.
29 - Patterson, K. L., J. W. Porter, K. B. Ritchie, S. W. Polson, E. Mueller, E. C. Peters, D. L. Santavvy, and G. W. Smith. 2002. The etiology of white pox, a lethal disease of the Caribbean elkhorn coral, Acropora palmata. Proc. Natl. Acad. Sci. USA 99:8725-8730.[Abstract/Free Full Text]
30 - Peters, E. C. 1997. Diseases of coral-reef organisms, p. 114-139. In C. Birkeland (ed.), Life and death of coral reefs. Chapman and Hall Publishers, London, United Kingdom.
31 - Porter, J., P. Dunstan, W. Jaap, K. Patterson, V. Kosmynin, O. Meier, M. Patterson, and M. Parsons. 2001. Patterns of spread of coral disease in the Florida Keys. Hydrobiologia 460:1397-1407.
32 - Rohwer, F., M. Breitbart, J. Jara, F. Azam, and N. Knowlton. 2001. Diversity of bacteria associated with the Caribbean coral Montastraea franksi. Coral Reefs 20:85-91.[CrossRef]
33 - Rohwer, F., V. Seguritan, F. Azam, and N. Knowlton. 2002. Diversity and distribution of coral-associated bacteria. Mar. Ecol. Prog. Ser. 243:1-10.[CrossRef]
34 - Stoecker, D. K., and M. W. Silver. 1990. Replacement and aging of chloroplasts in Strombidium capitatum (Ciliophora: Oligotrichida). Mar. Biol. 107:491-502.[CrossRef]
35 - Stoecker, D. K., M. W. Silver, A. E. Michaels, and L. H. Davis. 1989. Enslavement of algal chloroplasts by four Strombidium spp. Mar. Microb. Food Webs 3:79-100.
36 - Stoecker, D. K., M. W. Silver, A. E. Michaels, and L. H. Davis. 1988. Obligate mixotrophy in Laboea strobila, a ciliate which retains chloroplasts. Mar. Biol. 99:415-423.[CrossRef]
37 - Toller, W. W., R. Rowan, and N. Knowlton. 2002. Genetic evidence for a protozoan (phylum Apicomplexa) associated with corals of the Montastraea annularis species complex. Coral Reefs 21:143-146.
38 - Ulstrup, K. E., M. Kühl, and D. G. Bourne. 2007. Zooxanthellae harvested by ciliates associated with brown band syndrome of coral remain photosynthetically competent. Appl. Environ. Microbiol. 73:1968-1975.[Abstract/Free Full Text]
39 - van Oppen, M. J. H., F. Palstra, A. M.-T. Piquet, and D. J. Miller. 2001. Patterns of coral-dinoflagellate associations in Acropora: significance of local availability and physiology of Symbiodinium strains and host-symbiont selectivity. Proc. R. Soc. Lond. B 268:1759-1767.[Medline]
40 - Webster, N., D. G. Bourne, and M. Hall. 2006. Vibrio infection in phyllosomas of the tropical rock lobster Panulirus ornatus as detected by fluorescence in situ hybridisation. Aquaculture 255:173-178.[CrossRef]
41 - Weil, E. 2004. Coral reef diseases in the wider Caribbean: status and prognosis, p. 35-68. In E. Rosenberg and Y. Loya (ed.), Coral health and disease. Springer-Verlag, New York, NY.
42 - Willis, B. L., C. A. Page, and E. A. Dinsdale. 2004. Coral diseases on the great barrier reef, p. 69-104. In E. Rosenberg and Y. Loya (ed.), Coral health and disease. Springer-Verlag, New York, NY.
43 - Wilson, K. J., Y. Li, V. Whan, S. A. Lehnert, K. Byrne, S. S. Moore, S. Pongsomboon, A. Tassanakajon, G. Rosenberg, E. Ballment, Z. Fayazi, J. Swan, M. J. Kenway, and J. A. H. Benzie. 2002. Genetic mapping of the black tiger shrimp Penaeus monodon with amplified fragment length polymorphisms. Aquaculture 204:297-309.[CrossRef]
44 - Yarden, O., T. D. Ainsworth, G. Roff, W. Leggat, M. Fine, and O. Hoegh-Guldberg. 2007. Increased prevalence of ubiquitous Ascomycetes in an acropoid coral (Acropora formosa) exhibiting symptoms of brown band syndrome and skeletal eroding band disease. Appl. Environ. Microbiol. 73:2755-2757.[Abstract/Free Full Text]
Applied and Environmental Microbiology, February 2008, p. 883-888, Vol. 74, No. 3
0099-2240/08/$08.00+0 doi:10.1128/AEM.01124-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.