Fol. Biol. 2020, 66, 24-35

Domination of Filamentous Anoxygenic Phototrophic Bacteria and Prediction of Metabolic Pathways in Microbial Mats from the Hot Springs of Al Aridhah

Muhammad Yasir1,2, A. K. Qureshi2, S. Srinivasan3, R. Ullah2, F. Bibi1,2, M. Rehan1,4, S. B. Khan5, E. I. Azhar1,2

1Medical Laboratory Technology Department, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
2Special Infectious Agents Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
3Institute of Bioinformatics and Applied Biotechnology, Bangalore, Karnataka-560100, India
4King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia
5Department of Chemistry, King Abdulaziz University, Jeddah, Saudi Arabia

Received June 2019
Accepted November 2019

Microbial mats in hot springs form a dynamic ecosystem and support the growth of diverse communities with broad-ranging metabolic capacity. In this study, we used 16S rRNA gene amplicon sequencing to analyse microbial communities in mat samples from two hot springs in Al Aridhah, Saudi Arabia. Putative metabolic pathways of the microbial communities were identified using phylogenetic investigation of communities by reconstruction of unobserved states (PICRUSt). Filamentous anoxygenic phototrophic bacteria associated with phylum Chloroflexi were abundant (> 50 %) in both hot springs at 48 °C. Chloroflexi were mainly represented by taxa Chloroflexus followed by Roseiflexus. Cyanobacteria of genus Arthrospira constituted 3.4 % of microbial mats. Heterotrophic microorganisms were mainly represented by Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes. Archaea were detected at a lower relative abundance (< 1 %). Metabolic pathways associated with membrane transport, carbon fixation, methane metabolism, amino acid biosynthesis, and degradation of aromatic compounds were commonly found in microbial mats of both hot springs. In addition, pathways for production of secondary metabolites and antimicrobial compounds were predicted to be present in microbial mats. In conclusion, microbial communities in the hot springs of Al Aridhah were composed of diverse bacteria, with taxa of Chloroflexus being dominant.


This project work was funded by General Directorate of Research Grants (GDRG), King Abdulaziz City for Science and Technology (KACST), Saudi Arabia under grant number AT-12-33.


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