What is Microbial Life?
"Microbe" is a general term that encompasses almost any microscopic organism, including bacteria and archaea, which lack a cell nucleus or other membrane-bound cellular structures, and protists (mostly unicellular organisms that lack specialized tissues, and hence, are neither plant nor animal nor fungus). They can be found throughout the ocean, from rocks and sediments beneath the seafloor, across the vast stretches of open water, to intertidal and surf zones.
The diversity and number of microbes in the ocean far exceed that of macroscopic life, and many employ unique life strategies not seen anywhere else on Earth. Without them, life on Earth almost certainly would not be possible.
Some microbes are photosynthetic, deriving their energy from the sun. Below the photic zone (the uppermost, sunlit portion of the ocean), and especially at deep-ocean sites and around hydrothermal vents and seeps, microbes are chemosynthetic, meaning they derive energy from chemical reactions to drive their metabolic processes. Some microbes prey on others, some obtain carbon from inorganic sources, and some are scavengers that feed on dead organisms, fecal pellets, or other waste organic matter. Some can even consume hydrocarbons, aiding in the cleanup of oil from spills such as Deepwater Horizon. A few, such as diatoms and foraminifera, make hard, calcite “shells” that last for thousands of years in seafloor sediments and provide clues to past climate and ocean conditions.
Why is it important?
Ocean microbes play an important role in Earth's biogeochemical cycles, particularly the carbon, nitrogen, phosphorus, iron, and sulfur cycles. They also form the very base of the marine food chain, recycle nutrients and organic matter, and produce vitamins and cofactors needed by higher organisms to grow and survive. Many have evolved over millions of years to form symbiotic relationships with animals that allow the host animals to live in harsh or otherwise toxic environments, such as the hot, sulfur-rich waters around hydrothermal vents.
Some microbes are pathogens (toxic to humans and marine life) and result in billions of dollars lost or spent each year; others have resulted in billions of dollars and millions of lives saved through the development and production of pharmaceuticals or other commercial products.
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From Oceanus Magazine
Bridge-to-PhD program at WHOI opens doors for new scientists
WHOI’s Center for Chemical Currencies of a Microbial Planet (C-CoMP) works to expand BIPOC representation in ocean sciences with its inaugural Bridge-to-PhD Fellowship Program
A coral reef kickstart
WHOI’s Reef Solutions Initiative takes a multi-disciplinary approach to investigate solutions for ailing coral reefs
An estimated eight million tons of plastics enter our oceans each year, yet only one percent can be seen floating at the surface. This is the third in a three-part…
A Lobster Trap for Microbes
What if you wanted to observe what microbes in the ocean are doing? First, you lure them into your field of view.
The Unseen World on Coral Reefs
We have learned that microbial communities on and within us—a microbiome—keep people healthy. Corals reefs also have their own microbiomes that they couldn’t function without.