Details

Autor(en) / Beteiligte

• Uebe, René
• Schüler, Dirk

Titel

Magnetosome biogenesis in magnetotactic bacteria

Ist Teil von

• Nature reviews. Microbiology, 2016-10, Vol.14 (10), p.621-637

Ort / Verlag

London: Nature Publishing Group UK

Erscheinungsjahr

2016

Quelle

MEDLINE

Beschreibungen/Notizen

• Key Points The orientation of magnetotactic bacteria is based on the presence of unique organelles, magnetosomes, which are intracellular, membrane-enclosed, nanometre-sized crystals of magnetic iron minerals. In the past decade, substantial advances have been made in our understanding of magnetosome biogenesis using two genetically tractable Magnetospirillum species. Magnetosome biogenesis entails the invagination of the magnetosome membrane, recruitment of specific proteins, iron transport and redox-controlled biomineralization of magnetite crystals; magnetosomes are then assembled and positioned into well-ordered linear chains that are among the most complex structures seen in prokaryotic organisms. Key functions of magnetosome biogenesis are encoded by about 30 genes that are clustered in a genomic 'magnetosome island', although additional auxiliary functions are contributed by general cellular metabolic and regulatory pathways, including aerobic and anaerobic respiration. A non-magnetotactic bacterium has recently been 'magnetized' through the heterologous expression of genes that encode the magnetosome biogenesis pathway, which is a proof-of-principle demonstration that non-magnetotactic bacteria that are more facile for laboratory investigation could be 'magnetized' to provide new models for genetic dissection and synthetic biology. Bacterial magnetosomes are promising nanomaterials for various bioremediation, biomedical and bionanotechnological applications. Magnetosomes are unique organelles that 'magnetize' bacteria. In this Review, Uebe and Schüler discuss our current understanding of the mechanisms of magnetosome biogenesis, and consider how recent genetic advances in this area may lead to the development of exciting biotechnological applications. Magnetotactic bacteria derive their magnetic orientation from magnetosomes, which are unique organelles that contain nanometre-sized crystals of magnetic iron minerals. Although these organelles have evident potential for exciting biotechnological applications, a lack of genetically tractable magnetotactic bacteria had hampered the development of such tools; however, in the past decade, genetic studies using two model Magnetospirillum species have revealed much about the mechanisms of magnetosome biogenesis. In this Review, we highlight these new insights and place the molecular mechanisms of magnetosome biogenesis in the context of the complex cell biology of Magnetospirillum spp. Furthermore, we discuss the diverse properties of magnetosome biogenesis in other species of magnetotactic bacteria and consider the value of genetically 'magnetizing' non-magnetotactic bacteria. Finally, we discuss future prospects for this highly interdisciplinary and rapidly advancing field.