A microscopy image showing layers in different colors and a network of neurons

Department of
Biology

Photo of Sudha   Rajamani

Sudha Rajamani

Associate Professor and Deputy Chair, Biology

Biology

Origins of life

+91-20-25908061

srajamani@iiserpune.ac.in

Sudha Rajamani obtained her PhD (Biochemistry) in 2002 from the National Institute of Immunology at New Delhi. Subsequently, she joined the Fink lab at University of California in Santa Cruz (UCSC), USA, for a postgraduate research stint in the area of Parkinson's Disease. A change in her career trajectory led her to her current field of research in Astrobiology. She initiated her work in this area with a postdoctoral position at the Deamer lab in UCSC and completed with a postdoctoral position at the FAS Center for Systems Biology at Harvard University, prior to joining IISER Pune in 2012.

Research

Origins of life and its early evolution

How did life come about on Earth? What were the environmental conditions, niches and processes that set the stage for this unique event? Is there life elsewhere in the universe? The answers to these questions are far from beginning unravelled, making the “origins of life” question one of the greatest scientific mysteries that there is. The questions being pursued in this context in the COoL lab have fundamental implications for discerning how chemistry transitioned to biology on the early Earth. Specifically, we aim to delineate early Earth environments, niches and processes that would have supported self-assembly events pertinent to the emergence of the earliest cellular forms of life. Particularly, how polymers capable of catalysis and replication, and the membranes that eventually encapsulated them to form protocells, came about from the heterogenous prebiotic soup, is a central focus. Furthermore, we are characterizing how these molecules were sustained and propagated under early Earth conditions, and how they evolved new functions while resulting in the emergence of the first cellular forms. There are multiple projects pertaining to the aforementioned research interests that are being pursued. An important consideration while delineating all of the above is on systematically characterizing the role of molecular complexity on reactions that are fundamental to life’s emergence. Additionally, all the aforesaid processes are being evaluated in early Earth analogue sites, to characterize how they advent in ‘realistic’ scenarios. This allows us to glean how the physicochemical features of prebiotically pertinent sites, would have impinged on the emergence and evolution of early life.

Selected Publications

Sarkar, S. Dagar, S., Rajamani, S. (2021) Influence of Wet-dry Cycling on the Self-Assembly and Physicochemical Properties of Model Protocellular Membrane Systems. ChemSystemsChem, doi.org/10.1002/syst.202100014.

Joshi, M. P., Sawant, A. A., Rajamani, S (2021). Spontaneous emergence of membrane-forming protoamphiphiles from a lipid-amino acid mixture under wet-dry cycles. Chem. Sci, 12, 2970-2978.

Sarkar, S., Das, S., Dagar, S., Joshi, M. P., Mungi, C. V., Sawant, A. A., Patki, G.M. & Rajamani, S. Prebiological Membranes and Their Role in the Emergence of Early Cellular Life. Journal of Membrane Biol, 253(6):589-608.

Dagar, S., Sarkar, S., & Rajamani, S. (2020). Geochemical influences on nonenzymatic oligomerization of prebiotically relevant cyclic nucleotides. RNA, 26(6), 756-769.

Sarkar, S., Dagar, S., Verma, A., & Rajamani, S. (2020). Compositional heterogeneity confers selective advantage to model protocellular membranes during the origins of cellular life. Scientific Reports, 10(1), 1-11.

Roy, S., Bapat, N. V., Derr, J., Rajamani, S., & Sengupta, S. Emergence of ribozyme and tRNA-like structures from mineral-rich muddy pools on prebiotic earth. Journal of Theoretical Biology, 506, 1100446.

Bapat, N. V., & Rajamani, S. (2018). Templated replication (or lack thereof) under prebiotically pertinent conditions. Scientific Reports, 8(1), 15032.