Mapping the genetic landscape of biomineralization in Magnetospirillum magneticum AMB-1 with RB-Tnseq
Reads0
Chats0
TLDR
In this paper, random barcoded transposon mutagenesis (RB-TnSeq) was used to identify the global genetic requirements for magnetosome formation under different growth conditions.Abstract:
Magnetotactic bacteria (MTB) are a phylogenetically diverse group of bacteria remarkable for their ability to biomineralize magnetite (Fe3O4) or greigite (Fe3S4) in organelles called magnetosomes. The majority of genes required for magnetosome formation are encoded by a magnetosome gene island (MAI). Most previous genetic studies in MTB have focused on the MAI, using screens to identify key MAI genes or targeted genetics to isolate specific genes and their function in one specific growth condition. Here, we conducted random barcoded transposon mutagenesis (RB-TnSeq) in Magnetospirillum magneticum AMB-1 to identify the global genetic requirements for magnetosome formation under different growth conditions. We generated a library of 184,710 unique strains in a wild-type background, generating ~34 mutant strains for each gene. RB-TnSeq also allowed us to determine the essential gene set of AMB-1 under standard laboratory growth conditions. To pinpoint novel genes that are important for magnetosome formation, we subjected the library to magnetic selection screens in varied growth conditions. We compared biomineralization in standard growth conditions to biomineralization in high iron and anaerobic conditions, respectively. Strains with transposon insertions in the MAI gene mamT had an exacerbated biomineralization defect under both high iron and anerobic conditions compared to standard conditions, adding to our knowledge of the role of MamT in magnetosome formation. Mutants in amb4151, a gene outside of the MAI, are more magnetic than wild-type cells under anaerobic conditions. All three of these phenotypes were validated by creating a markerless deletion strain of the gene and evaluating with TEM imaging. Overall, our results indicate that growth conditions affect which genes are required for biomineralization and that some MAI genes may have more nuanced functions than was previously understood.read more
Citations
More filters
Journal ArticleDOI
Biomineralization and biotechnological applications of bacterial magnetosomes.
TL;DR: Magnetosomes intracellularly biomineralized by magnetotactic bacteria (MTB) are membrane-enveloped nanoparticles of the magnetic minerals magnetite (Fe3O4 or greigite) or magnetosomes as mentioned in this paper .
Journal ArticleDOI
Effect of oxic and anoxic conditions on intracellular storage of polyhydroxyalkanoate and polyphosphate in Magnetospirillum magneticum strain AMB-1
TL;DR: In this article , the influence of oxic, anoxic and transient oxic-anoxic conditions on intracellular storage of PHA and polyP in Magnetospirillum magneticum strain AMB-1 was investigated.
References
More filters
Journal ArticleDOI
Magneto-aerotaxis in Marine Coccoid Bacteria
TL;DR: It is reported that cells of a pure culture of a marine magnetotactic coccus, designated strain MC-1, formed microaerophilic bands in capillary tubes and used aerotaxis to migrate to a preferred oxygen concentration in an oxygen gradient.
Journal ArticleDOI
Mutant phenotypes for thousands of bacterial genes of unknown function
Morgan N. Price,Kelly M. Wetmore,Robert Jordan Waters,Mark Callaghan,Jayashree Ray,Hualan Liu,Jennifer V. Kuehl,Ryan A. Melnyk,Jacob S. Lamson,Yumi Suh,Hans K. Carlson,Zuelma Esquivel,Harini Sadeeshkumar,Romy Chakraborty,Grant M. Zane,Benjamin E. Rubin,Judy D. Wall,Axel Visel,Axel Visel,James Bristow,Matthew J. Blow,Adam P. Arkin,Adam P. Arkin,Adam M. Deutschbauer,Adam M. Deutschbauer +24 more
TL;DR: A large-scale mutagenesis screen identifies mutant phenotypes for over 11,000 protein-coding genes in bacteria that had previously not been assigned a specific function, demonstrating the scalability of microbial genetics and its utility for improving gene annotations.
Journal ArticleDOI
Rapid Quantification of Mutant Fitness in Diverse Bacteria by Sequencing Randomly Bar-Coded Transposons
Kelly M. Wetmore,Morgan N. Price,Robert Jordan Waters,Jacob S. Lamson,Jennifer He,Cindi A. Hoover,Matthew J. Blow,James Bristow,Gareth Butland,Adam P. Arkin,Adam P. Arkin,Adam M. Deutschbauer +11 more
TL;DR: An approach, random bar code transposon-site sequencing (RB-TnSeq), which greatly simplifies the measurement of gene fitness by using bar code sequencing (BarSeq) to monitor the abundance of mutants.
Journal ArticleDOI
Growth and magnetosome formation by microaerophilic Magnetospirillum strains in an oxygen-controlled fermentor
Udo Heyen,Dirk Schüler +1 more
TL;DR: Media and growth conditions were optimized for the microaerobic cultivation of Magnetospirillum gryphiswaldense in flasks and in a fermentor, resulting in significantly increased cell and magnetosome yields, compared with earlier studies, and provide the basis for large-scale cultivation of magnetospirilla under defined conditions.
Journal ArticleDOI
Ecology, Diversity, and Evolution of Magnetotactic Bacteria
TL;DR: The purpose of this review is focused on the diversity and the ecology of the MTB and also the evolution and transfer of the molecular determinants involved in magnetosome formation.