The pollution stemming from the use of petroleum by boats, the presence of deceased marine life, hazardous chemicals, and wastewater is a major issue in human-made commercial ports. This pollution poses a considerable challenge to the diverse organisms inhabiting the seawater. To comprehend the impact of this pollution on the microbiome, we conducted a study in which we collected surface water samples from a commercial port called Keelung Port, as well as a nearby offshore island known as Keelung Islet. These locations are situated in northern Taiwan, along the Northwestern Pacific Ocean. Through the use of whole-metagenome shotgun sequencing, we made an intriguing discovery regarding the bacterial composition in the seawater of Keelung Port. Pseudomonadota emerged as the predominant phylum, with notable abundance observed in Oceanospirillaceae, Rhodobacteraceae, Halieaceae, and Arcobacteraceae families. In contrast, Keelung Islet exhibited the highest abundance of Flavobacteriaceae, alongside a noteworthy presence of Euryarchaeota and Uroviricota. These findings provide compelling evidence of the significant impact human activities have on the microbial community within the seawater of commercial ports. These human activities cause notable alterations in the original microbial composition observed in Keelung Islet. Functional analysis of Kyoto Encyclopedia of Genes and Genomes (KEGG) and Clusters of Orthologous Groups of proteins (COG) revealed that microbes in the seawater of Keelung Port have the ability to degrade oil pollution, adapt to their environment through gene products for sulfur and nitrogen metabolisms, and exhibit hallmarks such as chemotaxis, biofilm formation, and secretion systems. Exploration of the microbial genome derived from the coastal seawater of the commercial port also led to the discovery of three distinct genomic islands, each harboring an array of genes. Within these genetic islands, we uncovered components such as tyrosine-type recombinase/integrase, DNA-invertase, immunity protein, helix-turn-helix domain, and glutathione-regulated potassium-efflux system protein. This significant finding indicates that genomic islands may act as pivotal elements in facilitating horizontal gene transfer. Such transfers enable microorganisms to adapt more effectively to the demanding and complex environment found within human-made port settings.
Shih, Chi-Yu; Chin, Ching-Hsiang; Chen, Shiow-Yi; Hsu, Chun-Ru; Kan, Lee-Kuo; and Tzou, Wen-Shyong
"Microbial community and genome structure in coastal seawater from a commercial port and nearby offshore island in northern Taiwan,"
Journal of Marine Science and Technology: Vol. 31:
4, Article 19.
Available at: https://jmstt.ntou.edu.tw/journal/vol31/iss4/19