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[Michaelangelica]

Bacteria Reveal Secret Of Adaptation At Evolution Canyon

ScienceDaily (July 30, 2008) — Bacteria living on opposite sides of a canyon have evolved to cope with different temperatures by altering the make-up of their 'skin', or cell membranes. Scientists have found that bacteria change these complex and important structures to adapt to different temperatures by looking at the appearance of the bacteria as well as their genes. The researchers hope their study, published in the August issue of Microbiology, will start a new trend in research.


'Evolution Canyons' I and II are in Israel. They are similar, each with a hot south-facing slope and a cooler north-facing slope. The sun-exposed 'African' south-facing slopes get eight times more solar radiation than the shady, green, lush 'European' north-facing slopes. Scientists studied 131 strains of Bacillus simplex and found that bacteria on different slopes have evolved differently, forming different 'ecotypes' of the same species.

Bacteria Reveal Secret Of Adaptation At Evolution Canyon

How Some Bacteria May Steal Iron From Their Human Hosts

ScienceDaily (Aug. 2, 2008) — Like their human hosts, bacteria need iron to survive and they must obtain that iron from the environment. While humans obtain iron primarily through the food they eat, bacteria have evolved complex and diverse mechanisms to allow them access to iron.


A Syracuse University research team led by Robert Doyle, assistant professor of chemistry in The College of Arts and Sciences, discovered that some bacteria are equipped with a gene that enables them to harvest iron from their environment or human host
. . .
Actinomycetes need lots of iron to wage chemical warfare on its enemies; however, iron is not easily accessible in the environments in which the bacteria live— e.g. human or soil. Some iron available in the soil is bonded to citrate, making a compound called iron-citrate. Citrate is a substance that cells can use as a source of energy

How Some Bacteria May Steal Iron From Their Human Hosts
SO. . .

• What happens when you seed the seas with iron? (As suggested by some to reduce CO2) Does this just effect phytoplankton? (See article on bacteria in sea producing methane in News thread)
• What happens in different soil pH environments/levels? Is more or less iron available? How does this change soil microbiology?
• What is the soil bacteria like in mountains of Iron- as exist in western Australia?
• What would adding iron or Iron citrate to garden/farm soil do to soll fertility and plant growth?
• Does addition of charcoal to soil change iron availability at all? It changes/increases bacteria so where does the extra iron needed come from?

Are Humans and other life just here to help the microbes?

Life on this planet is microbial," he said. "There is a vast amount going on in the microbial world that we don't understand. Microbes play significant roles in the carbon cycle, the nitrogen cycle, the phosphorous cycle, and we don't fully understand how."

Part of the reason microbes remain mysterious is the way they have traditionally been studied in the lab, Fields said. Researchers usually grow cultures of single microbe species and then explore how those monocultures react to different stimuli.

"But monocultures in the lab are not like the real world," Fields said. "Seldom do organisms grow on their own in a real ecosystem."

Instead, Fields looks at the complex systems and communities microbes form naturally. The goal, he said, is not necessarily to understand which single variable produces a certain reaction. Rather, the goal is to understand the key mechanisms that drive the entire system.

Fields uses this system-based approach to study how the microbial communities living at sites contaminated by toxic heavy metals, such as uranium and chromium, may help stop the spread of those contaminants.

Some forms of those heavy metals are soluble in water, allowing them to seep into groundwater and spread beyond the contaminated site.

But Fields explained that some of the microbes he studies can, just by going through their natural life processes, make those metals insoluble. Instead of spreading, the metals are deposited in solid form at the contamination site.

Microbiologists Studying Little-known But Largely Useful Microbes