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                    CLAIM FOR POTENTIAL CONFLICT OF INTEREST

                          ...with the COOLEST guys around the world

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

Q2: Community Yearning for The Strain? I wasn't wrong, were I? : )

During our review on 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 Take A Look At 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 one mentioning 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 your giving in lies mostly in its STRINGENT growth conditions required to be successfully cultivating these bacteria. It is a good reason, indeed.

To be frank about the truth, magnetotactic 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 for 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.

Obstacle 2: Lack of Genetic Toolbox

Sadly, there were way too many obstacles for previous iGemers when thinking about their magnetic fantasies. This has lead to only a few precedents proceeding into the stage where BIG questions lie. We lack any available genetic tools in Parts Registry!

To this date, provided with our utmost efforts in literature study, we've found, from previous researches on magnetotactic bacteria, two strains are capable of undergoing transformation--MSR-1 [13], and AMB-1 [14].

For the genetic manipulating system on MSR-1, Dirk Schüler, et al. have developed a stable and efficient method by conjugation with Escherichia coli S17-1. Plasmids used in the system are derivatives of pBBR1MCS (broad-host-range vector)