Project description:Rhodothermus marinus Alfredsson et al. 1995 is the type species of the genus and is of phylogenetic interest because the Rhodothermaceae represent the deepest lineage in the phylum Bacteroidetes. R. marinus R-10(T) is a Gram-negative, non-motile, non-spore-forming bacterium isolated from marine hot springs off the coast of Iceland. Strain R-10(T) is strictly aerobic and requires slightly halophilic conditions for growth. Here we describe the features of this organism, together with the complete genome sequence, and annotation. This is the first complete genome sequence of the genus Rhodothermus, and only the second sequence from members of the family Rhodothermaceae. The 3,386,737 bp genome (including a 125 kb plasmid) with its 2914 protein-coding and 48 RNA genes is part of the Genomic Encyclopedia of Bacteria and Archaea project.
Project description:To identify genes that are inhibited by mir-493, we have employed whole genome microarray expression profiling as a discovery platform to identify genes that are down-regulated after expression of mir-493. HCT116 colon cancer cells were transfected with control or mir-493 mimic for 24 hrs, and total RNA extracted from the transfected cells were labeled with Cy3 and used for microarray analyses with Agilent Whole Human Genome Oligo Microarrays.
Project description:Electron transfer in respiratory chains generates the electrochemical potential that serves as the energy source for ATP synthesis, solute transport and motility. In eukaryotes and many bacteria, the respiratory chain consists of four electron transport complexes, known as complex I to IV. Respiratory chains of some prokaryotes differ in composition and organization. They can use a wide range of electron donors and acceptors and may have complexes performing the same catalytic reaction. The diversity and apparent redundancy of prokaryotic respiratory chains reflects the versatility and robustness of the organisms. Many of these alternative respiratory chain complexes are either unknown or their structures and mechanisms remain elusive. In this work we describe a 3.9 A cryo-EM structure of the alternative complex III (ACIII) from Rhodothermus marinus, which we demonstrated takes over the role of canonical respiratory complex III (bc1 complex), even though it is structurally unrelated. Our structure reveals that ACIII is an integral membrane protein complex of at least 7 subunits (ActABCDEFH). The periplasmic domain, with ActA, B, E and H, harbours four iron-sulphur clusters and six C-type hemes. The cofactors form two electron wires that converge on the putative quinol-binding site in subunit ActC. The two homologous subunits, ActC and ActF, each have two four-helix bundles in the membrane, with several conserved polar residues that delineate putative proton channels. ACIII meets all requirements for an energy-transducing machine that couples electron transfer from quinol to the oxygen reductase, to translocation of protons across the membrane.