MAGNETOTACTIC BACTERIA (Syllabus: GS Paper 3 – Sci and Tech)

Context: Researchers have uncovered fossil remains of magnetic particles, known as magnetofossils produced by magnetotactic bacteria, in rock varnish layers in Ladakh, India.

Magnetotactic Bacteria

• About: These are mostly prokaryotic organisms that arrange themselves along the Earth’s magnetic field.
• Habitat: These bacteria are found in both freshwater and marine environments.
• Oxygen Navigation: Historically, it was believed that these bacteria follow the magnetic field to find optimal oxygen concentrations.
• Iron-Rich Compass: These organisms contain novel structured particles rich in iron, housed in small sacs that function as a compass.
• Crystal Formation: Magnetotactic bacteria produce tiny crystals of iron-rich minerals, magnetite or greigite, to navigate changing oxygen levels in their habitat.

Highlights of the Research

• Comparison: Researchers are examining similarities between rock varnish in Ladakh and those observed on Mars by the Perseverance rover.
• Organic Signatures Detection: Elevated concentrations of oxidized manganese (Mn4+) and carboxylic acid functionalities were identified on the varnish surface, indicating possible organic signatures.
• Biotic Origin of Magnetic Minerals: The findings suggest that the magnetic minerals in rock varnish are likely biotic in origin.
• Importance for Space Missions: Detecting biotic signatures in rock varnish enhances the focus on identifying biosignatures on Mars and other celestial bodies.
• Future Space Exploration: This information is essential for future space missions, including those planned by ISRO and other agencies, aiming to explore Mars and evaluate its habitability.