AUTHOR=Ma Liyuan , Yang Weiyi , Huang Shanshan , Liu Rui , Li Huiying , Huang Xinping , Xiong Junming , Liu Xueduan 

TITLE=Integrative Assessments on Molecular Taxonomy of Acidiferrobacter thiooxydans ZJ and Its Environmental Adaptation Based on Mobile Genetic Elements

JOURNAL=Frontiers in Microbiology

VOLUME=13

YEAR=2022

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2022.826829

DOI=10.3389/fmicb.2022.826829

ISSN=1664-302X

ABSTRACT=<p>Acidiferrobacter spp. are facultatively anaerobic acidophiles that belong to a distinctive <italic>Acidiferrobacteraceae</italic> family, which are similar to <italic>Ectothiorhodospiraceae</italic> phylogenetically, and are closely related to <italic>Acidithiobacillia</italic> class/subdivision physiologically. The limited genome information has kept them from being studied on molecular taxonomy and environmental adaptation in depth. Herein, <italic>Af. thiooxydans</italic> ZJ was isolated from acid mine drainage (AMD), and the complete genome sequence was reported to scan its genetic constitution for taxonomic and adaptative feature exploration. The genome has a single chromosome of 3,302,271 base pairs (bp), with a GC content of 63.61%. The phylogenetic tree based on OrthoANI highlighted the unique position of <italic>Af. thiooxydans</italic> ZJ, which harbored more unique genes among the strains from <italic>Ectothiorhodospiraceae</italic> and <italic>Acidithiobacillaceae</italic> by pan-genome analysis. The diverse mobile genetic elements (MGEs), such as insertion sequence (IS), clustered regularly interspaced short palindromic repeat (CRISPR), prophage, and genomic island (GI), have been identified and characterized in <italic>Af. thiooxydans</italic> ZJ. The results showed that <italic>Af. thiooxydans</italic> ZJ may effectively resist the infection of foreign viruses and gain functional gene fragments or clusters to shape its own genome advantageously. This study will offer more evidence of the genomic plasticity and improve our understanding of evolutionary adaptation mechanisms to extreme AMD environment, which could expand the potential utilization of <italic>Af. thiooxydans</italic> ZJ as an iron and sulfur oxidizer in industrial bioleaching.</p>