Comparative Proteomic Analysis of Psychrophilic vs. Mesophilic Bacterial Species Reveals Different Strategies to Achieve Temperature Adaptation

Abstract

The old debate of nature (genes) vs. nurture (environmental variables) is once again topical concerning the effect of climate change on environmental microorganisms. Specifically, the Polar Regions are experiencing a drastic increase in temperature caused by the rise in greenhouse gas emissions. This study, in an attempt to mimic the molecular adaptation of polar microorganisms, combines proteomic approaches with a classical microbiological analysis in three bacterial species Shewanella oneidensis, Shewanella frigidimarina, and Psychrobacter frigidicola. Both shewanellas are members of the same genus but they live in different environments. On the other hand, Shewanella frigidimarina and Psychrobacter frigidicola share the same natural environment but belong to a different genus. The comparison of the strategies employed by each bacterial species estimates the contribution of genome vs. environmental variables in the adaptation to temperature. The results show a greater versatility of acclimatization for the genus Shewanella with respect to Psychrobacter. Besides, S. frigidimarina was the best-adapted species to thermal variations in the temperature range 4–30°C and displayed several adaptation mechanisms common with the other two species. Regarding the molecular machinery used by these bacteria to face the consequences of temperature changes, chaperones have a pivoting role. They form complexes with other proteins in the response to the environment, establishing cooperation with transmembrane proteins, elongation factors, and proteins for protection against oxidative damage.

The hidden microbial ecosystem in the perennial ice from a Pyrenean ice cave

“…The samples incubated at 4°C presented a greater number of spots related to motility such as flagellin, tail protein, chemotaxis protein, and motor switch protein. When temperature rises, the ice melts and the liquid medium in veins between ice channels facilitates the movement of the cells ( García-Descalzo et al, 2022 ).…”

“…Living confined to ice, they are not affected by water currents, and they are rich in nutrients from soil dust and animal waste. An increase in temperature in a very stable environment like a cave can modify the microbial population composition and their mechanisms of adaptation, metabolism, and biogeochemistry ( García-Descalzo et al, 2022 ). Their molecular machinery may have been modified to adapt to temperature rise and to the changes in the chemical composition of the ice ( Garcia-Lopez et al, 2016 ; Garcia-Lopez and Cid, 2017 ).…”

Bacterial molecular machinery in the Martian cryosphere conditions

“…A pooled standard of samples A + AM or B + BM was labeled with Cy2 ( Supplementary Figure S3 ). After DTT addition, pairs of experimental and control samples were mixed and subjected to 2DE combining horizontal slab gel isoelectric focusing with SDS-PAGE as previously described ( García-Descalzo et al, 2022 ).…”

Identification and Regulatory Roles of a New Csr Small RNA from Arctic Pseudoalteromonas fuliginea BSW20308 in Temperature Responses

“…The cold environments are dominated by microorganisms which form the base of the food web ( 1 ). Microorganisms living in the cold biosphere have evolved sophisticated strategies to adapt to low temperatures ( 2 ). Meanwhile, climate change and global warming have become a threat to the biosphere, particularly the cold biosphere of the polar regions.…”