Role of the magnetosome proteins MamGFDC in biomineralization and size control of magnetite crystals in Magnetospirillum gryphiswaldense

• Applicant: Professor Dr. Dirk Schüler
• Subject Area: Microbial Ecology and Applied Microbiology
• Term: from 2010 to 2015
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 165534956

• Final Report Year: 2016

Final Report Abstract

Proteins encoded by the mamGFDC operon (mamGFDCop), together with those encoded by the adjacent mms6op account for the most abundant fraction of the entire magnetosome proteom in the alphaproteobacterium Magnetospirillum gryphiswaldense, however, their functions have been largely unknown. In this project we found that these magnetosome proteins are not essential for magnetite biomineralization, but together control size and shapes of the magnetite crystals during their maturation in a cumulative manner. Individual and combined overexpression caused gradual overproduction of larger and more magnetosomes. Unexpectedly, a subset of three paralogous MamF-like proteins was found to have a crucial function in the recruitment and targeting of other magnetosome biosynthetic factors.

Publications

• 2011. Functional analysis of the magnetosome island in Magnetospirillum gryphiswaldense: The mamAB operon is sufficient for magnetite biomineralization. Plos One 6:e25561
  Lohße A, Ullrich S, Katzmann E, Borg S, Wanner G, Richter M, Voigt B, Schweder T, Schüler D
  
• 2011. Magnetosome expression of functional camelid antibody fragments (nanobodies) in Magnetospirillum gryphiswaldense. Appl Environ Microbiol 77:6165-6171
  Pollithy A, Romer T, Lang C, Müller FD, Helma J, Leonhardt H, Rothbauer U, Schüler D
  
• 2014. Genetic dissection of the mamAB and mms6 operons reveals a gene set essential for magnetosome biogenesis in Magnetospirillum gryphiswaldense. J Bacteriol
  Lohße A, Borg S, Raschdorf O, Kolinko I, Tompa E, Posfai M, Faivre D, Baumgartner J, Schüler D
  
• 2014. New Vectors for Chromosomal Integration Enable High-Level Constitutive or Inducible Magnetosome Expression of Fusion Proteins in Magnetospirillum gryphiswaldense. Appl Environ Microbiol 80:2609-2616
  Borg S, Hofmann J, Pollithy A, Lang C, Schüler D
  
• 2015. An intracellular nanotrap re-directs proteins and organelles in live bacteria. mBio, 6(1):e02117-14
  Borg, S., F. Popp, J. Hofmann, H. Leonhardt, U. Rothbauer, and D. Schüler
  
• 2016. Overproduction of Magnetosomes by Genomic Amplification of Biosynthesis-Related Gene Clusters in a Magnetotactic Bacterium. Appl. Environ. Microbiol. 10: 3032-3041
  Lohße A, Kolinko I, Raschdorf O, Uebe R, Borg S, Brachmann A, Plitzko J, Müller R, Zhang Y, Schüler D