title: Comparative c-type cytochrome expression analysis in Shewanella oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C grown with soluble and insoluble oxidized metal electron acceptors.
abstract: The genomes of Shewanella oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C encode 40 and 69 putative c-type cytochrome genes respectively. Deletion mutant and biochemical studies have assigned specific functions to a few c-type cytochromes involved in electron transfer to oxidized metals in S. oneidensis strain MR-1. Although promising, the genetic approach is limited to gene deletions that produce a distinct phenotype and to an organism for which a genetic system is available. To investigate and compare c-type cytochrome expression in S. oneidensis strain MR-1 and Anaeromyxobacter dehalogenans strain 2CP-C more comprehensively, proteomic measurements were used to characterize lysates of cells grown with soluble Fe(III) (as ferric citrate) and insoluble Mn(IV) (as MnO2) as electron acceptors. Strain MR-1 expressed 19 and 20, and strain 2CP-C expressed 27 and 25, c-type cytochromes when grown with Fe(III) and Mn(IV) respectively. The majority of c-type cytochromes (77% for strain MR-1 and 63% for strain 2CP-C) were expressed under both growth conditions; however, the analysis also revealed unique c-type cytochromes that were specifically expressed in cells grown with soluble Fe(III) or insoluble Mn(IV). Proteomic characterization proved to be a promising approach for determining the c-type cytochrome complement expressed under different growth conditions, and will help to elucidate the specific functions of more c-type cytochromes that are the basis for Shewanella and Anaeromyxobacter respiratory versatility.
authors.affiliation: Graduate School of Genome Science and Technology, University of Tennessee, Knoxville, TN 37919, USA.
authors.forename: Silke
authors.initials: S
authors.lastname: Nissen
authors.forename: Xiaoxin
authors.initials: X
authors.lastname: Liu
authors.forename: Karuna
authors.initials: K
authors.lastname: Chourey
authors.forename: Robert L
authors.initials: RL
authors.lastname: Hettich
authors.forename: Darlene D
authors.initials: DD
authors.lastname: Wagner
authors.forename: Susan M
authors.initials: SM
authors.lastname: Pfiffner
authors.forename: Frank E
authors.initials: FE
authors.lastname: Löffler
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000235:genetics / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003574:Cytochrome c Group / Q000235:genetics / Q000378:metabolism*; D005290:Ferric Compounds / Q000378:metabolism; D015964:Gene Expression Regulation, Bacterial; D017895:Manganese Compounds / Q000378:metabolism; D058977:Molecular Sequence Annotation; D009231:Myxococcales / Q000235:genetics* / Q000378:metabolism; D010087:Oxides / Q000378:metabolism; D020592:Shewanella / Q000235:genetics* / Q000378:metabolism; D059467:Transcriptome
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D003574:Cytochrome c Group; D005290:Ferric Compounds; D017895:Manganese Compounds; D010087:Oxides; C025314:ferric citrate; C027424:manganese oxide