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  • Proteomic Insights into Psychrophile Growth in Perchlorate-Amended Subzero Conditions: Implications for Martian Life Detection

This content will become publicly available on March 1, 2026

Title: Proteomic Insights into Psychrophile Growth in Perchlorate-Amended Subzero Conditions: Implications for Martian Life Detection
Since the discovery of perchlorates in martian soils, astrobiologists have been curious if and how life could survive in these low-water, high-salt environments. Perchlorates induce chaotropic and oxidative stress but can also confer increased cold tolerance in some extremophiles. Though bacterial survival has been demonstrated at subzero temperatures and in perchlorate solution, proteomic analysis of cells growing in an environment like martian regolith brines-perchlorate with subzero temperatures-has yet to be demonstrated. By defining biosignatures of survival and growth in perchlorate-amended media at subzero conditions, we move closer to understanding the mechanisms that underlie the feasibility of life on Mars. Colwellia psychrerythraea str. 34H (Cp34H), a marine psychrophile, was exposed to perchlorate ions in the form of a diluted Phoenix Mars Lander Wet Chemistry Laboratory solution at -1°C and -5°C. At both temperatures in perchlorate-amended media, Cp34H grew at reduced rates. Mass spectrometry-based proteomics analyses revealed that proteins responsible for mitigating effects of oxidative and chaotropic stress increased, while cellular transport proteins decreased. Cumulative protein signatures suggested modifications to cell-cell or cell-surface adhesion properties. These physical and biochemical traits could serve as putative identifiable biosignatures for life detection in martian environments.  more » « less
Award ID(s):
2041497 2041748 2041435
PAR ID:
10630800
Author(s) / Creator(s):
; ; ; ; ; ;
Publisher / Repository:
Mary Anne Liebert publishers
Date Published:
Journal Name:
Astrobiology
Volume:
25
Issue:
3
ISSN:
1531-1074
Page Range / eLocation ID:
177 to 188
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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