1.Role of bacterial communities in coral’s defence against a causative agent of coral bleaching: Vibrio coralliilyticus
Thomas Höhener ; Ang Chung Huap ; Moritz Müller
Malaysian Journal of Microbiology 2016;12(4):279-283
Aims: Different studies have shown that members of the Vibrio such as Vibrio coralliilyticus and Vibrio shiloi are
opportunistic pathogens which can cause coral lysis. The aims of this study were to assess whether this results of the
virulence of V. coralliilyticus are transmittable to Acropora hyacinthus and Porites lobata, and what role the microbiome
of the corals plays during exposure to V. coralliilyticus.
Methodology and results: In laboratory-based experiments, we examined the impact of V. coralliilyticus (ATCC BAA-
450) to the microbiome of Acropora hyacinthus and Porites lobata. A. hyacinthus and P. lobata were exposed to
ampicillin, V. coralliilyticus, and a combination of both. Results indicate a resistance of A. hyacinthus to V. coralliilyticus
through the microbiome and underpin the importance of the microbiome for the coral’s health.
Conclusion, significance and impact study: Further studies are needed to identify the bacteria responsible for the
coral resistance and could in future lead to the development of a probiotic treatment or prevention of bleaching for
sensitive corals.
Microbiota
2.Shotgun metagenomic analysis of microbial communities in the surface waters of the Eastern South China Sea
Jessica Song ; Aazani Mujahid ; Po-Teen Lim ; Azizan Abu Samah ; Birgit Quack ; Klaus Pfeilsticker ; Sen-Lin Tang ; Elena Ivanova ; Moritz Müller
Malaysian Journal of Microbiology 2017;13(4):350-362
Aims: The South China Sea (SCS) harbours a rich biodiversity. However, few studies have been published on its
diverse communities, particularly its microbial counterparts. As key players behind many of the vital processes carried
out in the ocean, microbes are the focus of this study, placing particular emphasis on community composition, structure,
and function.
Methodology and results: By employing next generation shotgun sequencing technologies (Illumina HiSeq2000), we
assessed the taxonomic structure and functional diversity of the prokaryotic communities in surface waters collected
from 3 representative sites in the Eastern SCS: Sarawak (Kuching), Sabah (Kota Kinabalu), and Philippines (Manila).
Comparisons were undertaken to similar studies from coastal and open ocean environments. All 3 locations were
dominated by members of the Proteobacteria (Alpha- and Gamma-) and Cyanobacteria (Synechococcus sp. and
Prochlorococcus sp.). The highest proportion of Gammaproteobacteria was found in Sarawak, representing an
approximate 20% of total sequences. Archaeal assemblages were made up largely of Euryarchaeota and unclassified
sequences, while Crenarchaeota and Thaumarchaeota were present in much smaller proportions, except in the
Philippines where Thaumarchaeota made up almost 40% of the entire taxa.
Conclusion, significance and impact of study: The majority of the microbial communities adhered to a core set of
functional genes across the different locations. However, differences existed particularly in Sarawak waters which are
hypothesized to be due to local environmental parameters such as riverine influence. The results obtained from this
study provide the first comparison of prokaryotic communities in the surface waters of the eastern SCS and will serve as
a good platform for prospective studies in the field of environmental science.