In a study published online in Genome Research (www.genome.org), scientists have used genome sequencing to unlock new secrets about these magnetic microbes that could accelerate biotechnology and nanotechnology research.
Oxygen is essential for human life, but it is corrosive and poisonous to many bacteria. Magnetotactic bacteria evolved a clever method of using the Earth's magnetic field to orient itself and swim downward – exactly the direction a microbe must move to locate low oxygen areas in lakes and oceans. To find the direction of the magnetic field, these bacteria synthesize nanoscale cellular structures called magnetosomes that contain crystals of naturally occurring magnetic minerals.
The shape and composition of magnetosomes are species- and strain-specific, suggesting that magnetosome synthesis is biologically controlled. Magnetosomes are currently difficult to harvest in large quantities or synthesize artificially, therefore deciphering how cells form magnetosomes is crucial if they are to be useful in new technologies.
Genetic analyses have been performed in closely related magnetotactic bacteria, but because magnetosomes are also found in other classes of bacteria, scientists do not yet have a clear picture of the genetic components necessary for magnetosome formation. Tadashi Matsunaga of the Tokyo University of Agriculture and Technology and colleagues recognized that by analyzing the genome of more distantly related magnetotactic bacteria, researchers may be able to clearly define the minimal gene set needed for magnetosome synthesis.
In this work, Matsunaga's group sequenced the genome of Desulfovibrio magneticus strain RS-1, a more distant relative of other magnetotactic bacteria previously studied, and is also known for the unique bullet-shape of its magnetosomes. "Understanding the genes that control the morphology of these magnetosomes would be a significant breakthrough," said Matsunaga, noting that RS-1 could be the key to opening up new applications for magnetosomes.
Comparing the RS-1 genome sequence to the genomes of other magnetotactic bacteria, the team determined that all magnetotactic bacteria contain three separate gene regions related to magnetosome synthesis. Surprisingly, they also found that magnetosome-related genes are very well conserved across different classes of bacteria. Matsunaga explained that this suggests that the core magentosome genes may have been established in these bacteria by several horizontal gene transfer events, rather than being passed down through a lineage.
In addition to illuminating core magnetosome genes, the group expects that their work on RS-1 will be a stepping-stone to manipulation of magnetosomes for new technologies. Matsunaga said that further research with RS-1 "could open doors to the synthesis of morphologically controlled magnetosomes, and provide opportunities to their applications in electromagnetic tapes, drug delivery, magnetic resonance imaging, and cell separation."
Scientists from the National Institute of Technology and Evaluation (Tokyo, Japan) and the Tokyo University of Agriculture and Technology (Tokyo, Japan) contributed to this study.
This work was supported by the Ministry of Education, Culture, Sports, Science and Technology (MEXT) of Japan.
Tadashi Matsunaga, Ph.D. (email@example.com) has agreed to be contacted for more information.
Interested reporters may obtain copies of the manuscript from Peggy Calicchia, Editorial Secretary, Genome Research (firstname.lastname@example.org; +1-516-422-4012).
About the article:
The manuscript will be published online ahead of print on August 12, 2009. Its full citation is as follows: Nakazawa H, Arakaki A, Narita-Yamada S, Yashiro I, Jinno K, Aoki N, Tsuruyama A, Okamura Y, Tanikawa S, Fujita N, Takeyama H, Matsunaga T. Whole genome sequence of Desulfovibrio magneticus strain RS-1 revealed common gene clusters in magnetotactic bacteria. Genome Res doi:10.1101/gr.088906.108.
About Genome Research:
Launched in 1995, Genome Research (www.genome.org) is an international, continuously published, peer-reviewed journal that focuses on research that provides novel insights into the genome biology of all organisms, including advances in genomic medicine. Among the topics considered by the journal are genome structure and function, comparative genomics, molecular evolution, genome-scale quantitative and population genetics, proteomics, epigenomics, and systems biology. The journal also features exciting gene discoveries and reports of cutting-edge computational biology and high-throughput methodologies.
About Cold Spring Harbor Laboratory Press:
Cold Spring Harbor Laboratory is a private, nonprofit institution in New York that conducts research in cancer and other life sciences and has a variety of educational programs. Its Press, originating in 1933, is the largest of the Laboratory's five education divisions and is a publisher of books, journals, and electronic media for scientists, students, and the general public.
Genome Research issues press releases to highlight significant research studies that are published in the journal.
Peggy Calicchia | EurekAlert!
Enduring cold temperatures alters fat cell epigenetics
19.04.2018 | University of Tokyo
Full of hot air and proud of it
18.04.2018 | University of Pittsburgh
Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.
Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...
Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.
The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...
Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.
Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...
In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...
In an article that appears in the journal “Review of Modern Physics”, researchers at the Laboratory for Attosecond Physics (LAP) assess the current state of the field of ultrafast physics and consider its implications for future technologies.
Physicists can now control light in both time and space with hitherto unimagined precision. This is particularly true for the ability to generate ultrashort...
13.04.2018 | Event News
12.04.2018 | Event News
09.04.2018 | Event News
19.04.2018 | Materials Sciences
19.04.2018 | Physics and Astronomy
19.04.2018 | Physics and Astronomy