Identification of potential genes associated with magnetosome biogenesis in the CtrA regulon in Magnetospirillum magneticum AMB-1

Abstract

Magnetotactic bacteria (MTB) are worth studying because of magnetosome biomineralization. Magnetosome biogenesis in MTB is controlled by multiple genes known as magnetosome-related genes. Recent advances in microarray bioinformatics provide a unique opportunity for studying functions of magnetosome-related genes and networks that they are involved in. Furthermore, microarray analysis can also help identify genes potentially associated with magnetosome biogenesis. To find more magnetosome-related genes in the CtrA regulon, we analyzed expression data of 8 samples of Magnetospirillum magneticum AMB-1 in the GSE35625 dataset in NCBI GEO. We identified 10 potential magnetosome-related genes using a nearest neighbor search strategy on both protein-protein interaction and gene co-expression networks. We also discovered and compared two co-expression modules which most known magnetosome-related genes belong to. These analyses provided several clues for the importance of energy on regulating co-expression module structures. In addition, we hypothesized that many magnetosome-related genes may develop new abilities to interact with other biomolecules including their functions in magnetosome biogenesis during evolution, since they are not hub genes in networks. Overall, our study provides useful information for researches on magnetotactic bacteria and magnetosome.