[CDHC] new publications
Cheryl Woodley
cheryl.woodley at noaa.gov
Fri Jul 6 18:14:51 EDT 2007
Hi CDHC List Members,
As a means of encouraging more information and scientific discussion on
the CDHC list, I thought it may be helpful if you as members would post
a notification of your new papers with at least the citation and perhaps
even the abstract for those papers that are just hitting the press or as
an early notification for papers that are due to be coming out soon....
To start things off, Dr. Laurie Richardson (FIU) has offered up several
of her recent papers that are just out, as an example. (and offered to
help if you have trouble obtaining the pdf's, by contacting her
directly). The citations and abstracts are pasted below.
I encourage each of you to make use of the list serve to share your new
findings with the group as well.
Best Regards,
Cheryl
Here is 3 of Laurie's papers to kick things off.....
*Black Band Disease Microbial Community Variation on Corals in Three
Regions of the Wider Caribbean*
Joshua D. Voss, DeEtta K. Mills, Jamie L. Myers, Elizabeth R. Remily and
Laurie L. Richardson
Microbial Ecology
Published online: 28 March 2007, preprint
Abstract: Black band disease (BBD) is a pathogenic consortium of
microorganisms that primarily affects massive framework-building
scleractinian corals on reefs worldwide. There has been considerable
debate concerning the microbial community composition of BBD. The aim of
this study was to utilize microbial profiling to assess overall patterns
of variation in the BBD bacterial community with respect to geographic
location, host coral species, time, and nutrient regime. Length
heterogeneity polymerase chain reaction (LH-PCR) was employed to
differentiate BBD communities based on the natural variation in the
sequence lengths within hypervariable domains of the 16S rRNA gene.
Analysis of LH-PCR profiles of 97 BBD samples using multivariate
ordination methods and analysis of similarity revealed significant
clustering with respect to geographic region when comparing BBD sampled
from reefs near Lee Stocking Island in the Bahamas’ Exuma Chain, the
Northern Florida Keys (NFK), and St. John in the US Virgin Islands.
There was much variability in BBD community composition on a regional
basis, between sites in the NFK, and in terms of coral host species. The
observed differences among BBD microbial community profiles were driven
primarily by variation in relative abundance of 313–316-bp amplicons,
which correspond to cyanobacteria and α-proteobacteria. The results
obtained in this study support previous reports of intrinsic variability
and complexity of the BBD microbial community but also suggest that this
variability has biogeographic patterns.
*
The presence of the cyanobacterial toxin microcystin in black band
disease of corals*
Laurie L. Richardson, Raju Sekar, Jamie L. Myers, Miroslav Gantar, Joshua D.
FEMS Microbiol. Lett 272 (2007) 182-187.
Abstract
Black band disease (BBD) is a migrating, cyanobacterial dominated,
sulfide-rich microbial mat that moves across coral colonies lysing coral
tissue. While it is known that BBD sulfate-reducing bacteria contribute
to BBD pathogenicity by production of sulfide, additional mechanisms of
toxicity may be involved. Using HPLC/MS, the cyanotoxin microcystin was
detected in 22 field samples of BBD collected from five coral species on
nine reefs of the wider Caribbean (Florida Keys and Bahamas). Two
cyanobacterial cultures isolated from BBD, Geitlerinema and Leptolyngbya
sp. contained microcystin based on HPLC/MS, with toxic activity
confirmed using the protein phosphatase inhibition assay. The gene mcyA
from the microcystin synthesis complex was detected in two field samples
and from both BBD cyanobacterial cultures. Microcystin was not detected
in six BBD samples from a different area of the Caribbean (St Croix,
USVI) and the Philippines, suggesting regional specificity for BBD
microcystin. This is the first report of the presence of microcystin in
a coral disease.
*Microbial Communities in the Surface Mucopolysaccharide Layer and the
Black Band Microbial Mat of Black Band-Diseased Siderastrea siderea
*Raju Sekar, DeEtta K. Mills,Elizabeth R. Remily, Joshua D. Voss, and
Laurie L. Richardson
APPLIED AND ENVIRONMENTAL MICROBIOLOGY, Sept. 2006, p. 5963–5973 Vol.
72, No. 9
Microbial community profiles and species composition associated with two
black band-diseased colonies of the coral Siderastrea siderea were
studied by 16S rRNA-targeted gene cloning, sequencing, and
amplicon-length heterogeneity PCR (LH-PCR). Bacterial communities
associated with the surface mucopolysaccharide layer (SML) of apparently
healthy tissues of the infected colonies, together with samples of the
black band disease (BBD) infections, were analyzed using the same
techniques for comparison. Gene sequences, ranging from 424 to 1,537 bp,
were retrieved from all positive clones (n 43 to 48) in each of the
four clone libraries generated and used for comparative sequence
analysis. In addition to LH-PCR community profiling, all of the clone
sequences were aligned with LH-PCR primer sequences, and the theoretical
lengths of the amplicons were determined. Results revealed that the
community profiles were significantly different between BBD and SML
samples. The SML samples were
dominated by -proteobacteria (53 to 64%), followed by -proteobacteria
(18 to 21%) and -proteobacteria (5 to 11%). In contrast, both BBD clone
libraries were dominated by -proteobacteria (58 to 87%), followed by
verrucomicrobia (2 to 10%) and 0 to 6% each of -proteobacteria,
bacteroidetes, firmicutes, and cyanobacteria. Alphaproteobacterial
sequence types related to the bacteria associated with toxin-producing
dinoflagellates were observed in BBD clone libraries but were not found
in the SML libraries. Similarly, sequences affiliated with the family
Desulfobacteraceae and toxin-producing cyanobacteria, both believed to
be involved in BBD pathogenesis, were found only in BBD libraries. These
data provide evidence for an association of numerous toxin-producing
heterotrophic microorganisms with BBD of corals.
--
Cheryl Woodley, Ph.D.
Coral Health and Disease Program
DOC/NOAA/NOS/NCCOS
Center for Coastal Environmental Health and Biomolecular Research
Hollings Marine Laboratory
331 Fort Johnson Rd
Charleston, SC 29412
843.762.8862 Phone
843.762.8737 Fax
cheryl.woodley at noaa.gov
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