How did life appear on our planet?
A new study by the Rutgers scientists addressed these most profoundly unanswered questions in biology. Scientists have discovered the structures of proteins that could be leading players in the origins of life in the primordial soup of ancient Earth.
They determined the properties that defined life and concluded that anything alive needed to collect and use energy from sources such as the Sun or hydrothermal vents.
As proteins carry out most biological activities, scientists hence decided to explore the combination of the two- that is, proteins that bind metals.
The study’s lead author Yana Bromberg, a professor in the Department of Biochemistry and Microbiology at Rutgers University-New Brunswick, said, “We compared all existing protein structures that bind metals to establish any common features, based on the premise that these shared features were present in ancestral proteins and were diversified and passed down to create the range of proteins we see today.”
Scientists used a computational model that shows the vast majority of currently existing metal-binding proteins are somewhat similar regardless of the type of metal they bind to, the organism they come from, or the functionality assigned to the protein as a whole.
Bromberg said, “We saw that the metal-binding cores of existing proteins are indeed similar even though the proteins themselves may not be. We also saw that these metal-binding cores are often made up of repeated substructures, kind of like LEGO blocks. Curiously, these blocks were also found in other regions of the proteins, not just metal-binding cores, and in many other proteins that were not considered in our study. Our observation suggests that rearrangements of these little building blocks may have had a single or a small number of common ancestors and given rise to the whole range of proteins and their functions that are currently available — that is, to life as we know it.”
“We have very little information about how life arose on this planet, and our work contributes a previously unavailable explanation. This explanation could also potentially contribute to our search for life on other planets and planetary bodies. Our finding of the specific structural building blocks is also possibly relevant for synthetic biology efforts, where scientists aim to construct specifically active proteins anew.”
- Yana Bromberg et al. Quantifying structural relationships of metal-binding sites suggests origins of biological electron transfer. Science Advances, 2022; 8 (2) DOI: 10.1126/sciadv.abj3984