Sulfur Eating Party down in the SSCS... Bacis only.

Marine microbes have been within the earth’s oceans for billions of years. With the oceans spanning over 70% of the earth’s surface, most areas remain unstudied, despite the many forms of transportation and equipment now within our grasp. Studies of marine microbes have been evident in demonstrating vital roles in regulating ecological processes. This knowledge has proved critical as it has furthered our understanding of ocean mechanisms as well as insights to the behaviours of marine life. 

This research was undertaken to get a better understanding of the bacterial community within Malaysian Waters. It was performed within the benthic region of the Off-Terengganu Coastline of the Southern South China Sea, which previously had not been studied. This coastline in particular is heavily anthropogenically polluted due to the consistent commercial shipping. It is also home to a large breakwater structure used for coastal defences, further changing the diversity of species found. The breakwater structure creates a trapping effect on any run off within the sediment, effectively further polluting the harbour.

This research was conducted on the Terengganu Coastline, home to the largest shipping post in the world, due to this and industrialisation land run off the coastline is surrounded by high-quality crude oil clusters.  Despite this the Terengganu coastline has a shallow, ±50 m neritic epipelagic seabed, with a diverse abundance of tropical marine life forms.

Research Sampling commenced on the 30^th November 2014 via a Smith McIntre grab. Samples of subsurface bacteria were taken at random from 2 separate sites. Samples were kept in double layered polyethylene bags placed in -25ᵒc to be analysed via 16S rDNA V3-V4 marker gene on the Illumina™ Miseq platform. Area 1 showed a higher species richness than Area 2 by 70%. This is assumed to be due to the higher abundance of seagrass that contributes to the amount of organic matter in the water column. This is further illustrated by the diversity and abundance of microbes that also changes with depth, for Area 1 an increase in depth meant going deeper than that of seagrass abundance. Physiochemical parameters of the sediment showed inadequate results for hydrothermal vents within sample areas, although high traces of hydrocarbon pollutants such as gasoline, diesel and mineral oil were found.

  

Epsilonproteobacteria was the most dominant phylum with 60% (Area 1) and 88% (Area 2) followed by Gammaproteobacteria, Deltaproteobacteria and finally Alphaproteobacteria.  Sulfurovum sp., of Epsilonproteobacteria, predominated the overall bacterial community found, however several other sulphur oxidizing bacteria found however from the Gammaproteobacteria genus. This shows the potential for high rates adaptability for survival within as more then one phylum was discovered, pressing for further research based on bacterium metabolic adaptations to be performed. Sulvurofum sp. is an innate bacterium found generally within volcanic regions and deep hydrothermal vents, neither of which was found during the initial physiochemical parameters’ measurement. Metabolic adaptations have come into questioning, with the potential of this being an important role in regulating hydrocarbon pollutants for survival. This however requires further study, as well as future study on Sulvurofum sp. flexibility.

Overall it would seem that the pollution and breakwater structure combined have had a large effect on the ecosystem of the Terengganu Coastline. I believe further research is crucial to understand more about the adaptability of the microbes within this area as they play a vital roles within the regulation of the oceans ecological processes.   

Paper Origin: Abundance of sulfur-degrading bacteria in a benthic bacterial community of shallow sea sediment in the off-Terengganu coast of the South China Sea

 Zahar Marziah, Akbariah Mahdzir, Md. Nor Musa, Abu Bakar Jaafar, Azran Azhim & Hirofumi Hara