Seawater is not very exciting when you look at it. It is, presumably, just water with salt and other minerals. To most of the denizens of Earth’s oceans, the sea is something quite different, a web of gel.
According to an article from New Scientist magazine, published in November 2000, Farooq Azam, a microbial oceanographer at Scripps Institution of Oceanography said:
“This gel structure is something that oceanography has traditionally not considered. It’s not in the textbooks or in the classical explanations. The gel’s existence fundamentally changes our ideas of the microcosmos in which sea organisms live.”
It has long been known that, at the smallest scale, seawater is a mesh of interconnected long-chain polysaccharide molecules that can hold smaller molecules, and even organisms, in a kind of suspension; restricting their motions and aligning them in complex arrays. The Scripps Institute research found that these molecules provide a structure that makes seawater a matrix of isolated regions at the milliliter scale. Bacteria and plankton use that structure as unique ecologies in the same way that a forest provides niches for different kinds of life.
Most sugars are polar molecules: meaning, they are electrically charged. The valence bonds inside them between oxygen and hydrogen atoms give the oxygen a slight negative charge and the hydrogen a slight positive charge. In turn, polarized water molecules attract the negative and positive areas on the sugars, which makes them dissolve in water, where non-polar molecules will not…oil, for instance.
A nanoscale polysaccharide network. Credit: International Journal of Molecular Sciences, Vesna Svetličić, Vera Žutić, Galja Pletikapić and Tea Mišić Radić
As the New Scientist article states, some common phenomena are examples of the ocean’s gelatin-like substance. The northern Adriatic Sea turns to jelly every few years during algal blooms. However, the microscopic forces involved with the occurrence are not readily understood, nor is the way that the gel forms, in general.
A milliliter of seawater contains huge numbers of polysaccharide molecules that if “…untangled and lined up end to end, would stretch 5 600 kilometers (3 500 miles).” There are also chains of DNA, proteins, and other organic substances that provide a nutrient-rich environment for the organisms that live in the ocean. It does not answer how the web of gel forms, though. It is believed that the gel exists because bacterial and algal sugar excretions combine into a sticky soup, but that answer leaves many other questions.
Negatively charged polysaccharides are most likely interacting with positively charged ions like calcium, magnesium, and sodium in the seawater. This electro-chemistry aligns “exopolymer particles” into a “biological glue”, binding bacteria, proteins, and sheets of phytoplankton into the strands of gel that give microstructure to ocean water.
Bacteria and protein molecules are also electrical entities. Some bacteria can live off electrons, alone, synthesizing everything they need from the flow of charge. Bacteria can also eat iron, as well as drive their flagella with electric motors. Coupling these ideas with the research done by Gerald Pollack and others about “exclusion zone” water could provide answers to the questions of water, electricity and the environment that supports life.
Written by Stephen Smith – The Thunderbolts Project
Featured image: Turquoise Sea, Mauritius. Credit: flowcomm (CC – Flickr)