Whole-genome sequencing reveals adaptive strategies of the Antarctic aquatic bacterium Arthrobacter sp. R5.

Abstract

Arthrobacter species are widely distributed in cold environments and are recognized for their ability to withstand multiple environmental stressors. Here, we report the whole-genome sequence of Arthrobacter sp. R5, a red-pigmented and UV-resistant bacterium isolated from shallow lake sediments collected at Edmonson Point, Antarctica. Whole-genome sequencing was performed using the Illumina NovaSeq 6000 platform, and the genome was assembled and annotated using the TORMES workflow. The assembled genome comprises 4,145,062 bp with a GC content of 67.78% and contains 3700 predicted coding sequences, 57 tRNAs, three rRNA genes, and one tmRNA gene. Functional classification based on Clusters of Orthologous Groups (COG) revealed a predominance of genes involved in transcription, amino acid and carbohydrate metabolism, signal transduction, and replication, recombination and repair. The genome harbours several genes associated with DNA damage repair, including photolyases, the UvrABC nucleotide excision repair system and the UmuCD SOS response system, which may contribute to the UV resistance phenotype of strain R5. Genome mining further identified multiple biosynthetic gene clusters, including terpene-associated regions containing genes related to carotenoid biosynthesis, supporting the genetic potential underlying the characteristic red pigmentation of this strain. The genomic dataset presented here provides a valuable resource for investigating the molecular mechanisms of environmental adaptation in Antarctic bacteria and for exploring the biotechnological potential of stress-protective metabolites produced by polar microorganisms.