Current Microbiology

, Volume 64, Issue 6, pp 515–523

Screening for the Interacting Partners of the Proteins MamK & MamJ by Two-Hybrid Genomic DNA Library of Magnetospirillum magneticum AMB-1


DOI: 10.1007/s00284-012-0099-2

Cite this article as:
Pan, W., Xie, C. & Lv, J. Curr Microbiol (2012) 64: 515. doi:10.1007/s00284-012-0099-2


Magnetotactic bacteria are a group of prokaryotes capable of sensing and navigating along the earth’s magnetic field. The linear alignment of magnetosomes, which acts as a compass needle for orientation, is dependent on the proteins MamJ (amb0964) & MamK (amb0965). We constructed Magnetospirillum magneticum AMB-1 two-hybrid DNA libraries by fusing the random genomic fragments of AMB-1 to the N-terminal domain of the α-subunit of RNA polymerase in vector pTRG and used as preys. The genes mamJ & mamK were cloned in frame with the λ repressor protein (λ cI) in vector pBT and used as baits for screening the binding partners. After preliminary screening, we further confirmed the candidate interactions between selected protein pairs. The results showed that there were relatively strong interactions between MamK versus Amb3498 (flagella motor switch protein fliM), versus Amb0854 MCPs (signal domain of methyl-accepting chemotaxis protein) and versus Amb3568 (GGDEF domain-containing protein), respectively. MamJ versus Amb1722 (hypothetical protein), MamJ versus MamK, and MamK versus Amb1807 (cation transport ATPase) exhibited low level of interaction. Although the TPR repeat protein MamA (amb0971) showed no interaction with either MamJ or MamK, the TPR repeat protein Amb0024 with more motif sequences exhibited relatively strong interaction with MamK. Among the identified proteins, all categorized as signal transduction-related displayed interaction only with MamK and without MamJ, suggesting that magnetotaxis via MamK in Magnetospirillum magneticum AMB-1 might be somehow concerned with the widely accepted chemotaxis mechanism in bacteria.

Supplementary material

284_2012_99_MOESM1_ESM.doc (144 kb)
Supplementary material 1 (DOC 144 kb)

Copyright information

© Springer Science+Business Media, LLC 2012

Authors and Affiliations

  1. 1.Beijing Key Laboratory of Bioelectromagnetics, Institute of Electrical EngineeringChinese Academy of SciencesBeijingChina
  2. 2.Graduate University of Chinese Academy of SciencesBeijingChina
  3. 3.State Key Laboratory of Heavy Oil ProcessingChina University of PetroleumBeijingChina