Project description:Investigation of whole genome gene expression level in motile strain of Sphingomonas. sp A1 All flagellar genes in motile strain of Sphingomonas. sp A1 are highly transcribed. A two chip study using total RNA recovered from wild-type and motile strains of Sphingomonas. sp A1 grown in 0.5% alginate medium.
Project description:Citrobacter sp. strain A1, isolated from a sewage oxidation pond, is a facultative aerobe and mesophilic dye-degrading bacterium. This organism degrades azo dyes efficiently via azo reduction and desulfonation, followed by the successive biotransformation of dye intermediates under an aerobic environment. Here we report the draft genome sequence of Citrobacter sp. A1.
Project description:SP-A (surfactant protein A) is a membrane-associated SP that helps to maintain the lung in a sterile and non-inflamed state. Unlike SP-As from other mammalian species, human SP-A consists of two functional gene products: SP-A1 and SP-A2. In all the functions examined, recombinant human SP-A1 invariably exhibits lower biological activity than SP-A2. The objective of the present study was to investigate why SP-A2 possesses greater biological activity than SP-A1 and what advantage accrues to having two polypeptide chains instead of one. We analysed structural and functional characteristics of recombinant baculovirus-derived SP-A1, SP-A2 and co-expressed SP-A1/SP-A2 using a wide array of experimental approaches such as analytical ultracentrifugation, DSC (differential scanning calorimetry) and fluorescence. We found that the extent of supratrimeric assembly is much lower in SP-A1 than SP-A2. However, the resistance to proteolysis is greater for SP-A1 than for SP-A2. Co-expressed SP-A1/SP-A2 had greater thermal stability than SP-A1 and SP-A2 and exhibited properties of each protein. On the one hand, SP-A1/SP-A2, like SP-A2, had a higher degree of oligomerization than SP-A1, and consequently had lower K(d) for binding to bacterial Re-LPS (rough lipopolysaccharide), higher self-association in the presence of calcium and greater capability to aggregate Re-LPS and phospholipids than SP-A1. On the other hand, SP-A1/SP-A2, like SP-A1, was more resistant to trypsin degradation than SP-A2. Finally, the importance of the supratrimeric assembly for SP-A immunomodulatory function is discussed.
Project description:Nocardia sp. strain CS682 is a rare actinobacterium with a promising ability to produce secondary metabolites such as nargenicin A1 (an effective antibacterial compound) and IBR-3 (a UV-protectant molecule). Here, we report the complete genome sequence of Nocardia sp. CS682, obtained by PacBio sequencing as a single contig with 8,919,230?bp (GC content, 63.3%).
Project description:Sphingomonas sp. strain A1 has three endotype alginate lyases (A1-I, A1-II [family PL-7], and A1-III [family PL-5]), each of which is encoded by a single gene. In addition to those of these lyases, a gene (the A1-II' gene) showing significant identity with the A1-II gene was present in the bacterial genome and coded for an alginate lyase with broad substrate specificity. Since no expression of A1-II' was observed even in bacterial cells grown on alginate, the A1-II' gene was thought to be a silent gene derived from the A1-II gene, presumably through duplication, modification, and translocation.
Project description:Sphingomonas sp. strain A1, a Gram-negative bacterium, directly incorporates alginate polysaccharide into the cytoplasm through a periplasmic alginate-binding protein-dependent ATP-binding cassette transporter. The polysaccharide is degraded to monosaccharides via the formation of oligosaccharides by endo- and exotype alginate lyases. The strain A1 proteins for alginate uptake and degradation are encoded in both strands of a genetic cluster in the bacterial genome and inducibly expressed in the presence of alginate. Here we show the function of the alginate-dependent transcription factor AlgO and its mode of action on the genetic cluster and alginate oligosaccharides. A putative gene within the genetic cluster seems to encode a transcription factor-like protein (AlgO). Mutant strain A1 (?AlgO mutant) cells with a disrupted algO gene constitutively produced alginate-related proteins. DNA microarray analysis indicated that wild-type cells inducibly transcribed the genetic cluster only in the presence of alginate, while ?AlgO mutant cells constitutively expressed the genetic cluster. A gel mobility shift assay showed that AlgO binds to the specific intergenic region between algO and algS (algO-algS). Binding of AlgO to the algO-algS intergenic region diminished with increasing alginate oligosaccharides. These results demonstrated a novel alginate-dependent gene expression mechanism. In the absence of alginate, AlgO binds to the algO-algS intergenic region and represses the expression of both strands of the genetic cluster, while in the presence of alginate, AlgO dissociates from the algO-algS intergenic region via binding to alginate oligosaccharides produced through the lyase reaction and subsequently initiates transcription of the genetic cluster. This is the first report on the mechanism by which alginate regulates the expression of the gene cluster.
Project description:Enterococcus sp. strain C1 is a facultative anaerobe which was coisolated with Citrobacter sp. strain A1 from a sewage oxidation pond. Strain C1 could degrade azo dyes very efficiently via azo reduction and desulfonation in a microaerophilic environment. Here the draft genome sequence of Enterococcus sp. C1 is reported.
Project description:The tenacious association between strains of the heterotrophic alphaproteobacterial genus Acidiphilium and chemolithotrophic iron oxidizing bacteria has long been known. In this context the genome of the heterotroph Acidiphilium sp. JA12-A1, an isolate from an iron oxidizing mixed culture derived from a pilot plant for bioremediation of acid mine drainage, was determined with the aim to reveal metabolic properties that are fundamental for the syntrophic interaction between Acidiphilium sp. JA12-A1 and the co-occurring chemolithoautotrophic iron oxidizer. The genome sequence consists of 4.18 Mbp on 297 contigs and harbors 4015 protein-coding genes and 50 RNA genes. Additionally, the molecular and functional organization of the Acidiphilium sp. JA12-A1 draft genome was compared to those of the close relatives Acidiphilium cryptum JF-5, Acidiphilium multivorum AIU301 and Acidiphilium sp. PM DSM 24941. The comparative genome analysis underlines the close relationship between these strains and the highly similar metabolic potential supports the idea that other Acidiphilium strains play a similar role in various acid mine drainage communities. Nevertheless, in contrast to other closely related strains Acidiphilium sp. JA12-A1 may be able to take up phosphonates as an additional source of phosphor.