Oceans are a rich and biodiverse habitat on its own. We can find organisms and plants ranging from a few millimetres to a length of 12 meters which is the size of the largest whale which weights close 50 tonnes. The vastness and the richness of the oceans are a wonder to study and explore a curious mind.
Scientists for many decades have believed that arsenic is a poisonous chemical for almost all living beings but until recently researchers have found a microorganism that lives by breathing Arsenic and is found over a large area in the Pacific ocean. The study has been published in The Proceedings of the National Academy of Sciences. Scientists have believed that this species had used arsenic during the time of formation of Earth where the presence of oxygen was limited and microorganism had to survive on arsenic. In the face of global warming, there is a need to adapt which is slowly happening in the ocean ecosystem as organisms need to be able to adapt to lower levels of oxygen in the water.
Arsenic was known to be present in water for quite a long time but its use by microorganism for living was quite a new concept. These microorganisms were discovered off the coast of Mexico where there is a patch called anoxic where there is virtually no oxygen dissolved in water. Microorganisms which breath on sulphur and nitrogen were known for quite a long time but living on arsenic is still new to researchers.
Scientists have analyzed the DNA samples of these microorganisms and found two pathways which convert arsenic-based molecules to energy resource. It has opened gateways to explore the life where oxygen does not exist and also extraterrestrial life on other planets might take place. These arsenic-based microorganisms might account for around one percent of the total marine microbial community but there is scope to find and understand the complex chemical reactions which happen in oceans as a whole.
Scientists think that the best way to study these microorganisms is to artificially grow these samples in the lab and study their metabolism and how they respond to various levels of arsenic content in water.
Jaclyn Saunders, a researcher has commented that the coolest thing about these organisms is that they are expressing the genes in an environment that is very low on arsenic and that it opens up boundaries to finding other organisms that are respiring arsenic in poor arsenic conditions.
The amount of diversity one may find on the Earth may surprise anyone, there are a lot more opportunities and organisms that are waiting to be explored in the depth and the vastness of our Earth’s oceans.