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For millions of years, our planet earth has stood still against the human race’s countless endeavors for destruction. Nevertheless, it has become apparent in recent years that earth’s defenses may be failing, and that through the uncontrollable use of fossil fuels, global warming strikes as earth’s faint cry for help. With humans being reluctant to listen, we are already witnessing the consequences.
However, the answer to earth’s problems lies in plain sight to those who are wise enough to look. The scientists of East Anglia University and Ocean University China investigated marine microorganisms, a mysterious yet fascinating field that was often neglected in the past, their findings could be a promising step in controlling global warming.
A marine alphaproteobacterium, namely Labrenzia aggregata is a breakthrough discovery in the role of bacteria in the sulfur cycle and climate control.
It was previously thought that only eukaryotes contributed to the cycle, but Labrenzia aggregata was found to convert dimethyl sulfoniopropionate (DMSP) into dimethyl sulfide (DMS) through the methionine transamination pathway. DMSP is a nutrient for marine microorganisms and a precursor for DMS.
DMS plays a major role in climate control, it is oxidized in the atmosphere into sulfate aerosols which form cloud condensing nuclei that absorb UV radiation lowering atmospheric temperatures and counteracting the greenhouse effect, in addition, these clouds transfer sulfur from ocean to land contributing to the sulfur cycle.
Labrenzia aggregata is the first discovered heterotrophic bacterium that is able to produce DMSP through de novo production of methionine through its acquisition of the dsyB gene, which encodes a methyltransferase enzyme.
This provides further evidence that DMSP production is not restricted to phototrophs on the surface of the ocean, but extends through its entire depth.
Finally, the discovery that a single gene transfer between different strains allowed DMSP production is remarkable. Will this transfer enable us to recruit other heterotrophs in combating global warming? Could Alphaproteobacteria be our salvation or is it only a few Labrenzia strains? The possibilities are endless and the prospects are exciting! The world is eager to see what the ocean has yet to offer.

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The term “superbug” is nothing new to the microbiology world but has only been under the spotlight for a few years, which consequently led to an increasing interest in antibiotic resistance by researchers. A superbug refers to a multidrug resistant bacterium which can therefore cause untreatable and fatal infections. This particular aspect has sparked global worry that our known antibiotics will eventually fail us.

With the interest in superbugs at its highest, scientists from Indiana University and Harvard University had their share in the investigation, using multi-colored dyes called fluorescent D-amino acids (FDAAs), aka rainbow dyes, which turned out to be just as cheerful to the researchers as actual rainbows. These dyes enabled them to visualize the detailed process of cell division, particularly the movement of the filaments FtsZ and FtsA (cytoskeletal polymers and prokaryotic homologs of the protein tubulin) that determine the site of cell division by driving peptidoglycan synthesizing enzymes to the correct sites. Cytokinesis starts with the formation of a Z-ring at the site of cell division, and both FtsZ and FtsA are required for this process.

When visualized, the filaments appeared to move in circular concentric rings, in a movement which was described as “treadmilling” in which the FtsZ filament loses a molecule at one end and gains a molecule at the other end, resulting in the circular motion. With the guidance of these rings, peptidoglycan was shown to begin forming a septum dividing the cell.

A more detailed aspect of the FtsZ and FtsA system is the lack of any means to convert chemical energy into mechanical force. However, the rearrangement is primarily dependent on FtsZ polymerization dynamics under the influence of conflicting regulation by FtsA, first, by promoting FtsZ assembly and second, by inhibiting FtsZ network organization. The result of this regulation is the formation of higher ordered structures by FtsZ as tubules, circles and sheets.

These findings might be a magnificent aid in combating superbugs by visualizing so accurately their division and offering a broader comprehension of their mechanisms.

Finally, if you ever find yourself anxious about superbugs, just remember: there always comes a RAINBOW after a rainy day.


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