This week, I’m featuring the MolBio Picks of the Week, which are normally brought to you by Alejandro over at MolBio Research Highlights. MolBio Picks of the Week brings you the best biology posts from researchblogging.org. I’ll give a brief description of all selected post and urge you to check out the posts yourselves, and leave a comment behind on the selected posts!
1. Multicellular bacteria
All bacteria are single-celled species, that’s common knowledge. Or is it? Lab Rat discusses a review paper that gives an overview of multicellularity in the prokaryotic world. To be considered multicellular, an organism has to consist of multiple cells that stick together, these cells have to communicate with each other and some of the cells have to have different jobs.
Can bacteria do all that? Not very many of them can, true, or there would be large multicellular bacterial ‘animals’ roaming the plains. But there are a number of photosynthetic bacteria are able to form truly multicellular structures, albeit rather small ones.
The suspects are photosynthesizing cyanobacteria that stick together to form a large string. Some of the cells in the string are able to fix nitrogen, whereas the other cells are able to generate energy via aerobic respiration. Both cell types are completely dependent on each other, and cannot live by themselves.
Cyanobacteria that display a form of multicellularity: they're attached to each other like beads on a string.
2. African trypanosomes just love social networking
Continuing with the theme of surprising multicellularity, a blog post appeared on geek!, covering research on the parasite that causes sleeping sickness, Trypansoma Brucei. This parasite was always thought to be single celled, but recent research suggests that several parasites can clump together into a single multicellular community. The group of parasites can move like a single entity and even sends out ‘scout parasites’ that can steer the main group.
3. “Codon” is now a four letter word
Normally, the genetic code is interpreted as combinations of three DNA bases. Iddo Friedberg from Byte Size Biology blogs about an exciting paper that introduces four letter codons. The group of Jason Chin basically reinvented the genetic code. These new four letter codons are free to code for any amino acids, even unnatural amino acids with exciting new properties. While this has been tried before, this was always done by modifying the existing translation machinery. It provides scientists with a whole new avenue of tinkering with the cell!
Diatoms under a microscope. Source: Wikipedia
4. Getting a sinking feeling yet?
On Demon-Haunted World, Ph.D. student Stephen discusses the strategy of using phytoplankton to sequester carbon dioxide. Since iron seems to be a limiting nutrient for plankton, some scientists have proposed to ‘seed’ the oceans with iron so that plankton can bloom and take up more CO2 from the environment. There’s a big if though, as the oceans get more and more acidic due to increasing CO2 levels, the uptake of iron by the plankton is severely limited. Stephen sums it up as following:
So where does this leave us? First, that ocean acidification is the 500-pound gorilla in the room that few (if any) in the mainstream media are talking about. Second, that the effects of acidification may be even worse than we first thought, if it results in a reduction in biological availability of iron to phytoplankton.
Well, these were my picks of last week on researchblogging. Enjoy!
Flores, E., & Herrero, A. (2009). Compartmentalized function through cell differentiation in filamentous cyanobacteria Nature Reviews Microbiology, 8 (1), 39-50 DOI: 10.1038/nrmicro2242
Oberholzer M, Lopez MA, McLelland BT, & Hill KL (2010). Social motility in african trypanosomes. PLoS pathogens, 6 (1) PMID: 20126443
Neumann, H., Wang, K., Davis, L., Garcia-Alai, M., & Chin, J. (2010). Encoding multiple unnatural amino acids via evolution of a quadruplet-decoding ribosome Nature DOI: 10.1038/nature08817
Shi, D., Xu, Y., Hopkinson, B., & Morel, F. (2010). Effect of Ocean Acidification on Iron Availability to Marine Phytoplankton Science, 327 (5966), 676-679 DOI: 10.1126/science.1183517
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Wow…nice work. Looks really pretty with all the pictures and things, and thanks for featuring the multicellular bacteria :)
Great job Lucas! A fascinating new issue of Picks of the Week.
I agree with LabRat: I may start using pictures in future issues.
Thanks again for hosting!