Diversity, Composition, Taxa Biomarkers, and Functional Genes of Fish Gut Microbes in Peat Swamp Forests and its Converted Areas in North Selangor, Malaysia

Abstract

The aquatic organisms in peat swamp forests are under threat due to habitat degradation resulting from human activities. This study determines the fish gut microbes’ diversity, composition, taxa biomarkers, and functional genes in peat swamp forests and its converted areas in North Selangor, Malaysia. Three undisturbed and disturbed areas nearby the peat swamp forests were selected. First, the 16S amplicon metagenomic analysis was conducted to assess the composition and diversity of bacterial communities in fish gut contents from both areas. Then, Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt) and Linear discriminant analysis Effect Size (LEfSe) were used to predict disease/pathogen related functional genes. This study revealed Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria as the predominant phyla in both studied areas. In contrast, bacterial community profiles of disturbed and undisturbed areas were slightly dissimilar. Metagenome predictions revealed that genes are related to metabolism, environmental information processing, genetic information processing, cellular processes, human diseases, and organismal systems. Further investigation revealed six potential biomarker genes, including chronic myeloid leukaemia in an undisturbed area, Vibrio cholerae infection, bladder cancer, pathogenic Escherichia coli infection, Staphylococcus aureus infection, and pertussis in disturbed areas. This study revealed that the fish gut microbiome could be used as an indicator in comparing the undisturbed and disturbed ecosystems.

The diversity, distribution, biomass, and conservation status of ichthyofauna of the Singkil peat swamp in Aceh Province, Indonesia

“…The low diversity in the Singkil peat swamp was thought to be related to habitat perturbation by land conversion to oil palm plantations, leading to the dryness of several river channels and swamps. However, the total species of fish in the Singkil peat swamp was higher than peat swamp in the Yak Yah peat swamp, Terengganu, West Coast of Peninsular Malaysia i.e., 14 species out of 95 individuals, and peat swamp in the North Selangor i.e., 9 species out of 43 individuals (Hussin-Jasmin et al 2021;Saadu et al 2021). The biomass analysis showed that the average value in the Singkil peat swamp was 288.75 kg/ha, where the fish species with the highest value was C. striata (1027.09 kg/ha), followed by C. batrachus (634.96 kg/ha).…”

“…Peat swamp is known to have a high potential for fish diversity, but there are limited studies on the presence of Ichthyofauna in the area. At present, There were two reports from Malaysia, i.e., in the Kampung Yak Yah peat swamp, Terengganu, West Coast of Peninsular Malaysia, which reported 14 species of fish and is the first report of peat swamp fish species in the area (Hussin-Jasmin et al 2021), and in the peat swamp in North Selangor, Malaysia, which recorded nine fish species (Saadu et al 2021). There are only four related reports from Indonesia, including Paada et al (2022) on Mempawah and Duri River peat swamp, West Kalimantan, which reported six species from both areas.…”