Distinctive microbial community and genome structure in coastal seawater from a human-made port and nearby offshore island in northern Taiwan facing the Northwestern Pacific Ocean

• Published in: PloS one 2023-06, Vol.18 (6), p.e0284022-e0284022
• Main Authors: Shih, Chi-Yu, Chen, Shiow-Yi, Hsu, Chun-Ru, Chin, Ching-Hsiang, Chiu, Wei-Chih, Chang, Mei-Hung, Kang, Lee-Kuo, Yang, Cing-Han, Pai, Tun-Wen, Hu, Chin-Hwa, Hsu, Pang-Hung, Tzou, Wen-Shyong
• Format: Article
• Language: English
• Subjects: Amino acids; Ammonium; Analysis; Annotations; Antibiotic resistance; Antibiotics; Antitoxins; Bacteria; Biofilms; Biological products; Biology and Life Sciences; Boats; Branched chain amino acids; Carbohydrate metabolism; Carbohydrates; Cell walls; Chain branching; Chemotaxis; Chromium; Coastal structures; Composition; Contamination; Denitrification; Deoxyribonucleic acid; DNA; DNA topoisomerase; Dominant species; Drug resistance; Drug resistance in microorganisms; Earth Sciences; Ecology and Environmental Sciences; Environmental impact; Fishing; Flagella; Gene sequencing; Genes; Genomes; Genomic islands; Genomic structural variations; Genomics; Health aspects; Horizontal transfer; Integrase; Invertase; Islands; Lipopolysaccharides; Marine pollution; Medicine and Health Sciences; Metabolism; Methods; Microbiomes; Microbiota; Microorganisms; Nitrogen fixation; Nitrogen metabolism; Nitrogenation; Nitroimidazole; Nucleotide sequence; Oceans; Pathogens; Pollution; Ports; Prevention; Research and analysis methods; Rhodobacteraceae; RNA; rRNA 16S; Sea-water; Seawater; Surface water; Taxonomy; Virulence factors
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0284022

Pollution in human-made fishing ports caused by petroleum from boats, dead fish, toxic chemicals, and effluent poses a challenge to the organisms in seawater. To decipher the impact of pollution on the microbiome, we collected surface water from a fishing port and a nearby offshore island in northern Taiwan facing the Northwestern Pacific Ocean. By employing 16S rRNA gene amplicon sequencing and whole-genome shotgun sequencing, we discovered that Rhodobacteraceae, Vibrionaceae, and Oceanospirillaceae emerged as the dominant species in the fishing port, where we found many genes harboring the functions of antibiotic resistance (ansamycin, nitroimidazole, and aminocoumarin), metal tolerance (copper, chromium, iron and multimetal), virulence factors (chemotaxis, flagella, T3SS1), carbohydrate metabolism (biofilm formation and remodeling of bacterial cell walls), nitrogen metabolism (denitrification, N2 fixation, and ammonium assimilation), and ABC transporters (phosphate, lipopolysaccharide, and branched-chain amino acids). The dominant bacteria at the nearby offshore island (Alteromonadaceae, Cryomorphaceae, Flavobacteriaceae, Litoricolaceae, and Rhodobacteraceae) were partly similar to those in the South China Sea and the East China Sea. Furthermore, we inferred that the microbial community network of the cooccurrence of dominant bacteria on the offshore island was connected to dominant bacteria in the fishing port by mutual exclusion. By examining the assembled microbial genomes collected from the coastal seawater of the fishing port, we revealed four genomic islands containing large gene-containing sequences, including phage integrase, DNA invertase, restriction enzyme, DNA gyrase inhibitor, and antitoxin HigA-1. In this study, we provided clues for the possibility of genomic islands as the units of horizontal transfer and as the tools of microbes for facilitating adaptation in a human-made port environment.