Multipartite genomes and the sRNome in response to temperature stress of an Arctic Pseudoalteromonas fuliginea BSW20308

Abstract

Summary Little is known about the survival and effect of rapid climate warming on Pseudoalteromonas in the Arctic, although it is abundant and important in this ecosystem. Here, we investigated a cold‐adapted Pseudoalteromonas fuliginea BSW20308 from the Arctic Ocean, from the genome to its transcriptomic responses towards temperature changes. It contained two circular chromosomes, with the second chromosome probably evolved from an ancestral plasmid. The evolution of multipartite genomes may be advantageous for its survival under changing environments. RNA‐seq analysis revealed the extensive involvement of sRNome in response to temperature stress for the first time, especially tmRNA and a novel Pf1 sRNA strongly induced under heat stress. The present study makes significant contributions towards the understanding of Pseudoalteromonas in two aspects: the genome structure and evolution of its two chromosomes, and the important discovery of the sRNome in response to temperature stress.

The Pseudoalteromonas multipartite genome: distribution and expression of pangene categories, and a hypothesis for the origin and evolution of the chromid

“…These two observations strongly support that the chromid was acquired by the most recent LCA of Pseudoalteromonadaceae , likely in a single event (indicated with an arrow in Figure 1 ). A single origin of the chromid is supported by a phylogenetic analysis that showed congruent phylogenies between the chromosome and chromid ( Liao et al 2019 ). Finally, two separate estimates of time since divergence suggest that Pseudoalteromonadaceae branched off approximately 500, and 502–378 million years ago ( Liao et al 2019 ; Xie et al 2021 ).…”

“…SRR11593423, SRR11593424, and SRR11593425), and 4° (sample no. SRR11593426, SRR11593427, and SRR11593428) ( Liao et al 2019 ) were downloaded from the NCBI Sequence Read Archive (Leinonen et al 2011) and analyzed. The quality of the reads was checked using FastQC ( Andrews 2010 ).…”

“…Furthermore, they estimated the last common ancestor (LCA) of Pseudoalteromonas to contain an estimated 2999 genes, compared to an average of 4245 genes in the present-day genomes, which supports that the genome has undergone a considerable expansion. More recently, Liao et al (2019) studied the evolution of the Pseudoalteromonas genome ( Liao et al 2019 ). Using a phylogenetic approach and timescale analysis, they showed that the chromosome and chromid have coexisted, probably since Pseudoalteromonas diverged from the putative LCA 500 million years ago.…”

“…Using a phylogenetic approach and timescale analysis, they showed that the chromosome and chromid have coexisted, probably since Pseudoalteromonas diverged from the putative LCA 500 million years ago. The chromid apparently originates from a megaplasmid that over time obtained essential genes ( Médigue et al 2005 ; Rong et al 2016 ; Liao et al 2019 ; Xie et al 2021 ).…”

Small RNAs as Fundamental Players in the Transference of Information During Bacterial Infectious Diseases

“…A recent study has evaluated the transcriptomic response of the psychrotrophic bacterium Pseudoalteromonas fuliginea BSW20308, which is adapted to Arctic environmental conditions (Liao et al, 2019). The aim was to evaluate the impact of global warming over the ecologically dominant genus, where temperature increases may trigger regulation mediated by sRNA.…”