Baker’s yeast has the resilience to withstand Martian environment: Study

Researchers from the Department of Biochemistry, Indian Institute of Science (IISc) and collaborators at the Physical Research Laboratory (PRL), Ahmedabad, have found that Baker’s yeast (Saccharomyces cerevisiae) has the resilience to withstand harsh conditions found in the Martian environment.

Baker’s yeast (Saccharomyces cerevisiae) is an indispensable ingredient in making bread, beer, and biotechnology products.

IISc said that this organism holds clues to how life could survive in extraterrestrial conditions and the findings underscore how baker’s yeast could serve as an excellent model for India’s efforts in astrobiology research.

It said that the team exposed yeast cells to high-intensity shock waves — similar to those produced by meteorite impacts on Mars — and perchlorate salts, which are toxic chemicals found in Martian soil.

Using a High-Intensity Shock Tube for Astrochemistry (HISTA) in Bhalamurugan Sivaraman’s lab at PRL, they simulated shock waves reaching Mach 5.6 intensity. The team also treated yeast cells with 100 mM sodium perchlorate either in isolation or in combination with the shockwaves.

“One of the biggest hurdles was setting up the HISTA tube to expose live yeast cells to shock waves — something that has not been attempted before — and then recovering yeast with minimum contamination for downstream experiments,” said lead author Riya Dhage.

IISc said that the yeast cells survived when treated with shock waves and perchlorate, individually and in combination, although the cells’ growth slowed down.

Key to resilience

“The likely key to their resilience lies in their ability to produce ribonucleoprotein (RNP) condensates — tiny, membrane-less structures that help protect and reorganise mRNA when the cells are under stress. Shock waves triggered the assembly of two types of RNPs called stress granules and P-bodies, while perchlorate exposure led to the generation of P-bodies alone. Yeast mutants that were unable to form these structures were far less likely to survive,” IISc said.

It added that the results show how RNP condensates may act as biomarkers for cellular stress under extraterrestrial conditions.

“What makes this work unique is the integration of shock wave physics and chemical biology with molecular cell biology to probe how life might cope with such Mars-like stressors,” said Ms. Dhage.

“We were surprised to observe yeast surviving the Mars-like stress conditions that we used in our experiments. We hope that this study will galvanise efforts to have yeast on board in future space explorations,” added Purusharth I. Rajyaguru, Associate Professor in the Department of Biochemistry.