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Bacteria, microbes, single-cell organisms - the planet is teeming with them, literally in the billions. There are tens of thousands in a single drop of seawater and, worldwide, they constitute the greatest biomass on Earth. If their numbers are an indication of success then perhaps that success is due to both the simplicity of their existence and their ability to adapt to changing environments.
Two recent announcements regarding these tiniest of creatures caught my eye (no pun intended) because they had to do with the aquatic world and involved places I've been or would very much like to be.
Bacteria that challenges our notions of life
In the arid, alien-like landscape of Mono Lake, researchers have found bacteria that has adapted to an arsenic-rich environment. What is most unusual in this adaption was that the bacteria incorporated arsenic into its basic metabolic structure, replacing phosphorus. This is rather unique as phosphorus is one of nature's building blocks for all living things. Scientists have long held that carbon, hydrogen, nitrogen, oxygen, sulfur, and phosphorus are the basic elements of life as they help make up nucleic acids, proteins, lipids, and other fundamental components of all living matter.
However, researchers from Arizona State University have found in the water of Mono Lake, in east central California, bacteria that has exchanged phosphorus for the more prevalent arsenic, thereby challenging our notions of what constitutes what or where life can exist either here on Earth or elsewhere.
"At the moment we have no idea if life is just a freak, bizarre accident which is confined to Earth or whether it is a natural part of a fundamentally biofriendly universe in which life pops up wherever there are Earth-like conditions," said Paul Davies, the Arizona State University and NASA Astrobiology Institute researcher.
The researchers are very cautious not to draw too many conclusions from this preliminary research. Though the implications are tantalizing, with the possibility of life forms on other planets based on a totally different structure than what exists on Earth, there is still a considerable amount of work to be done before scientists decide to re-define our established notions of what constitutes life. Still, it makes you wonder just what our planetary probes in space should be looking for.
John Elliot, a UK researcher who has been involved in the search for extraterrestrial life, said, "It starts to show life can survive outside the traditional truths and universals that we thought you have to use... this is knocking one brick out of that wall."
Microbes that went down with the ship, way down
Ever since I read my parent's original copy of A Night to Remember by Walter Lord when I was a child, I have had a soft spot for anything Titanic. I'm not alone in this fascination with the great 
ocean liner that epitomized both man's industrial might and arrogance. But while the name and the vessel represent all things huge, scientists also study some of the wreck's smallest features - like a new form of iron-eating bacteria.
The genus Halomonas covers salt water bacteria that slowly breakdown metals, typically leaving behind evidence of their handiwork in the form of long, trailing icicle-like structures known as rusticles. Covering the Titanic along its hull and decaying metal superstructure, rusticles form a bizarre wintry scene to remind us of the cold depth 2.5 miles below the surface where the ship lies in two great pieces.
Reported in the International Journal of Systematic and Evolutionary Microbiology, researchers from universities in Ontario, Canada and Seville, Spain have discovered a new bacteria, named Halomonas titanicae, by studying rusticle samples taken by the Russian submersible, Mir 2, 
back in 1991. Cultured in the lab from the 19-year old samples, these bacteria are of interest beyond just the fascination in lifeforms that are able to survive in some of the planet's harshest environments. The fate of offshore oil and gas pipelines at the hands of these metal-devouring microbes is an important area of research, particularly in the aftermath of this year's Gulf of Mexico oil spill. Additionally, understanding how these smallest of creatures can breakdown and possibly "recycle" some of mankind's largest structures could assist in developing safe and effective disposal methods of ships and oil rigs.
From the deepest depths of the ocean to perhaps beyond the stars, life continues to show scientists that it has a tenacious drive to survive, adapting to its surroundings sometimes in the most fundamental of ways.
Read about the arsenic bacteria in BBC News.
Read Titanic microbe study in the IJSEM journal.
With only a few days remaining before the start of Discovery Network's annual Shark Week, circulating through several news agencies (even Discovery's own Discovery News) is word of a new wrinkle in shark predatory behavior, a new weapon in its arsenal as it were: deadly bacteria.
Detailed in an article in the Journal of Zoo and Wildlife Medicine, a study was conducted by researchers who examined nearly 200 of seven different species of shark (and one species of redfish) from Martha's Vineyard in Massachusetts to the Florida Keys, the Louisiana coast, and south to Belize. Taking swab samples from the fishes' cloaca (its genital opening), strong evidence of deadly Staphylococcus and E. coli along with a host of other bacteria was found. These are bacteria that are life-threatening as they have become highly drug-resistant over the years - one of the side effects of man's extensive use (some might say overuse) of antibiotics.
Drug-resistant diseases and bacteria have been an issue with the medical community for some time, but here is a documented study showing transference of these microbes to fish. The question is: how did they get there?
As reported in Discovery News, one of the researchers, Jason Blackburn at Florida Atlantic University, has some theories. "Drugs given to humans could simply be excreted and eventually find their way into the ocean. Or bacteria in humans could acquire the resistance, be excreted, and then colonize fish that sharks eat, or the sharks, themselves. Some antibiotics are routinely dumped into aquaculture to help prevent infections -- that could be a source for some of the resistance."
The bacteria apparently is causing no harm to the sharks; perhaps the sharks are acting like host carriers, as occurs with other animals. But due to the drug-resistant nature of these bacteria, the 
potential for harm to man by casual contact or perhaps through eating raw meat can not be discounted. The research team plans on another study to investigate that aspect of the problem.
Today, we are learning more and more about the way in which pollutants like methylmercury and other toxic substances can work their way up through the food chain and often collect in surprisingly strong levels in many of the ocean's large predators including sharks, tuna, dolphins and more."You don't expect to see multi drug resistance from these animals because they shouldn't be exposed to antibiotics," said Adam Schaefer, a co-researcher involved in the study. "These animals are at the top of the food chain; they reflect everything that's going on beneath them."
When I dive with sharks, I'm less concerned with their teeth than with their overall attitude and posturing. Looks like now I'll have to check to see if their running a temperature.
Read an abstract from the study in the Journal of Zoo and Wildlife Medicine.
Read the article from Discovery News.
The growth of Nanotechnology - the science of developing compounds at an extremely small, molecular level - has brought some interesting developments, from new pharmaceuticals to our odor-eating, anti-bacterial socks. But with the emergence of this new field there also has grown concerns that it might turn out to be a substantially sharp two-edge sword.
Many of these new nano-compounds can enter the environment and scientists are just beginning to see the implications. When these compounds enter aquatic ecosystems, the impacts may appear very subtle at first because the components of the ecosystem affected are they themselves quite small. Scientists are looking at the effects of nano-compounds like various metals or carbon-based particles on aquatic bacteria, algae, and small fish.
As an example, one recent study indicated that "carbon black nanoparticles" affect the fertilization of brown algae. And there is concern that the silver nanoparticles used as an odor-remover in socks can, when released through machine washing, impact the bacteria that is necessary in breaking down organic matter - a very important function in water treatment facilities, lakes, rivers, and oceans. When any aquatic system loses its ability to consume organic matter, you are looking at a major and probably fatal disruption of the entire balance of the ecosystem.
While we focus on aquatic pollutants that are more visible - like plastics, crude oil, and discharged chemicals, we must also hold commercial science responsible for the effects of even the smallest of compunds that are entering the water, land, and air. I have great faith in science, but whether for commercial or purely research purposes, it must be held to the highest standards in balancing the rewards versus the impact on the planet.
Discussions of climate change often focus on the big events that can catch the attention of the public - hurricanes, fires and flooding, vast sea melts, etc. But what can be most alarming are the subtle, microscopic changes that can have enormous consequences.
I was reading the latest Marine Science Review available from Seaweb.org (No. 267 - Pathogens, disease, and die-offs). It covers everything from epizootic shell disease in lobsters to wasting disease in burrowing starfish, and much more. Many of these events are isolated or cyclical outbreaks, but increases in water temperature is becoming more and more of a potential factor.
Increases in water temperature - even very small changes - can produce two negative effects: an increase in bacteria and viral microorganisms, and a weakening of the immune system of many aquatic life forms. Will Nature adjust to these changes? Most likely, but at what cost to various species?
To borrow the Biblical phrase, the meek shall inherit the earth. But it may not be the banner-waving, peacenik; it may be something smaller than the head of a pin - meek but deadly. Another important aspect of climate change that has to be considered.
Bacteria, microbes, single-cell organisms - the planet is teeming with them, literally in the billions. There are tens of thousands in a single drop of seawater and, worldwide, they constitute the greatest biomass on Earth. If their numbers are an indication of success then perhaps that success is due to both the simplicity of their existence and their ability to adapt to changing environments.
However, researchers from Arizona State University have found in the water of Mono Lake, in east central California, bacteria that has exchanged phosphorus for the more prevalent arsenic, thereby challenging our notions of what constitutes what or where life can exist either here on Earth or elsewhere.
ocean liner that epitomized both man's industrial might and arrogance. But while the name and the vessel represent all things huge, scientists also study some of the wreck's smallest features - like a new form of iron-eating bacteria.
back in 1991. Cultured in the lab from the 19-year old samples, these bacteria are of interest beyond just the fascination in lifeforms that are able to survive in some of the planet's harshest environments. The fate of offshore oil and gas pipelines at the hands of these metal-devouring microbes is an important area of research, particularly in the aftermath of this year's Gulf of Mexico oil spill. Additionally, understanding how these smallest of creatures can breakdown and possibly "recycle" some of mankind's largest structures could assist in developing safe and effective disposal methods of ships and oil rigs.
