From 2011.igem.org

Revision as of 10:56, 5 October 2011

  

Magnetotactic bacteria, also known as magnetic bacteria, are an evolutionarily diverse group [1] of motile, Gram-negative eubacteria expressing magnetotaxis.

Yearning for This Strain: I wasn't wrong, were I? iGemers  : )

During our review in past iGem projects, we concluded, to more or less an extend, teams dreaming for magnetotaxis have concluded in using this strain......yet only two team ever actually tried. One of them was Duke University 2006, the other being us.

Below are several arguments about the choice of this strain and reasons stopping previous iGem teams / supporting us in standing soundly on this step.

So Let's Look Back on the iGem History

Throughout the history of iGem, we’ve gained notice from exhaustive online searching that a remarkable number of previous iGem teams have continually proposed projects related to magnetosome, magnetospirillum, and magnetotaxis every year around the world.

Among these respectful pioneers, Duke University had made their magnetotactic bacteria-based project to the official jamboree titled “Bacterial Dynamo”, focusing on the use of AMB-1 as AC voltage generator [12], but somehow limited by the lack of genetic manipulation toolkits for Magentospirillum magneticum AMB-1.

What’s worth mentioning was the diversity of ideas regarding the application of magnetotactic bacteria proposed by a great variety of iGem teams (See Table 1). This even led to a mention on 2009 iGem official website about “magnetic bacteria” as one of the Ideas for Bacteria.

Obstacle 1: Hard to Cultivate

Yes, we've heard your voice, iGemers. We knew from your previous/current brainstorming pages that the main reason for giving in to magnetic fantasies lies mostly in its STRINGENT growth conditions.

To be frank about the truth, strains capable of pure culture are only a few. Among them, Magnetospirillum magnetotacticum MS-1 [2], Magnetospirillum gryphiswalden MSR-1 [3], and Magnetospirillum magneticum AMB-1 [4] are used most frequently in researches on magnetotactic bacteria. In recent years, significantly improved cultivating methods of MS-1 [5], MSR-1 [6], and AMB-1 [7] have also been achieved. These have lead to the field buzzing about the realization of applications spanning fMRI reporting, tumor targeting, etc., using magnetites produced by these cells [8, 9, 10, 11]. To be honest, we also encountered some problems in cultivating strain AMB-1, but finally a complete cultivating method has been established here. See Chassis for more details.