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Genomic insights from a long-read assembly of a deep-sea Chromohalobacter israelensis strain from Santos Basin pockmarks field

Aug 2026 · Brazilian Journal of Microbiology · Vol 57 · 0 citations · 86 references
Medicine

TL;DR

Analysis revealed genes for metabolizing diverse carbohydrate sources, a complete ectoine synthesis cluster essential for halophily, and genes conferring tolerance to osmotic stress, low temperatures, and pH, underscoring its polyextremophilic capacity.

Abstract

Continental slopes, particularly the pockmark and salt diapir regions of the Santos Basin, represent extreme environments characterized by high hydrostatic pressure, low temperatures, elevated salinity, and limited organic matter, fostering unique bacterial communities. This study aimed to elucidate the metabolic strategies enabling survival in these conditions by exploring the genome of a Chromohalobacter israelensis strain isolated from such sediments, utilizing long-read sequencing. The genome, assembled into a single 3.8 Mb contig with 98.9% completeness, confirmed the strain’s taxonomic identity. Analysis revealed genes for metabolizing diverse carbohydrate sources, a complete ectoine synthesis cluster essential for halophily, and genes conferring tolerance to osmotic stress, low temperatures, and pH, underscoring its polyextremophilic capacity. Pangenome analysis identified a substantial core genome with essential metabolic functions, including a species-exclusive sulfur metabolism reaction. These findings highlight the strain’s biotechnological potential and contribute to understanding the genus’s adaptation to diverse hypersaline habitats and the strain’s potential role in the sampled environment.

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