Thermoanaerobacter tengcongensis is a rod-shaped, gram-negative, anaerobic eubacterium that was isolated from a freshwater hot spring in Tengchong, China. Using a whole-genome-shotgun method, we sequenced its 2,689,445-bp genome from an isolate, MB4T (Genbank accession no. AE008691). The genome encodes 2588 predicted coding sequences (CDS). Among them, 1764 (68.2%) are classified according to homology to other documented proteins, and the rest, 824 CDS (31.8%), are functionally unknown. One of the interesting features of the T. tengcongensis genome is that 86.7% of its genes are encoded on the leading strand of DNA replication. Based on protein sequence similarity, the T. tengcongensis genome is most similar to that of Bacillus halodurans, a mesophilic eubacterium, among all fully sequenced prokaryotic genomes up to date. Computational analysis on genes involved in basic metabolic pathways supports the experimental discovery that T. tengcongensis metabolizes sugars as principal energy and carbon source and utilizes thiosulfate and element sulfur, but not sulfate, as electron acceptors. T. tengcongensis, as a gram-negative rod by empirical definitions (such as staining), shares many genes that are characteristics of gram-positive bacteria whereas it is missing molecular components unique to gram-negative bacteria. A strong correlation between the G + C content of tDNA and rDNA genes and the optimal growth temperature is found among the sequenced thermophiles. It is concluded that thermophiles are a biologically and phylogenetically divergent group of prokaryotes that have converged to sustain extreme environmental conditions over evolutionary timescale

OBJECTIVE: To investigate whether prohibitin (PHB) is a target gene in adipocyte differentiation and modulates insulin-induced adipocyte differentiation. DESIGN: 3T3-L1 preadipocyte overexpressing wild-type PHB and PHB mutant (lacking tyrosine-114 phosphorylation site) with or without insulin. RESULTS: The treatment of 3T3-L1 fibroblasts with insulin or peroxisome proliferator-activated receptor-g agonist resulted in an upregulation of PHB in a dose-and time-dependent manner. An analysis of the PHB promoter sequence revealed the presence of putative insulin-response elements and CCAAT/enhancer-binding protein transcription elements within B1 kb upstream of the translation initiation site. The functional relevance of these sites was determined using reporter gene assay. Surprisingly, PHB was also found to be regulated by leptin. Furthermore, the overexpression of PHB in 3T3-L1 fibroblasts was sufficient to induce adipogenesis. CONCLUSION: In summary, we have identified PHB as an important protein in adipocyte differentiation.

BackgroundThe development of multidrug resistance is a major problem in the treatment of pathogenic microorganisms by distinct antimicrobial agents. Characterizing the genetic variation among plasmids from different bacterial species or strains is a key step towards understanding the mechanism of virulence and their evolution.ResultsWe applied a deep sequencing approach to 206 clinical strains of Klebsiella pneumoniae collected from 2002 to 2008 to understand the genetic variation of multidrug resistance plasmids, and to reveal the dynamic change of drug resistance over time. First, we sequenced three plasmids (70 Kb, 94 Kb, and 147 Kb) from a clonal strain of K. pneumoniae using Sanger sequencing. Using the Illumina sequencing technology, we obtained more than 17 million of short reads from two pooled plasmid samples. We mapped these short reads to the three reference plasmid sequences, and identified a large number of single nucleotide polymorphisms (SNPs) in these pooled plasmids. Many of these SNPs are present in drug-resistance genes. We also found that a significant fraction of short reads could not be mapped to the reference sequences, indicating a high degree of genetic variation among the collection of K. pneumoniae isolates. Moreover, we identified that plasmid conjugative transfer genes and antibiotic resistance genes are more likely to suffer from positive selection, as indicated by the elevated rates of nonsynonymous substitution.ConclusionThese data represent the first large-scale study of genetic variation in multidrug resistance plasmids and provide insight into the mechanisms of plasmid diversification and the genetic basis of antibiotic resistance.

We investigated the effects of a high-fructose (HF) diet on cardiovascular risks in Sprague-Dawley rats. Twelve rats were randomly assigned to standard chow or HF diet for 20 weeks. Systolic blood pressure and circulating insulin, total cholesterol, and triacylglycerol levels were significantly higher in the HF group. Aortic sections appeared normal, but liver sections from the HF group showed lipid accretion, mild inflammation, and bile pigmentation. Liver samples from the HF group showed significantly higher total lipid levels and changes in fatty acid profile. Levels of 16:0, cis-9-18:2, cis-11-20:1, cis-13-20:1, cis-11-20:2 and 24:0 were significantly raised in the phospholipid fraction. Lower levels of cis-11-18:1, cis-9-18:2, and cis-11-20:1 and increased levels of 16:1, cis-9-18:1, and cis-13-20:1 were found in the non-esterified fatty acid fraction. HF-feeding resulted in significant reductions in plasma levels of certain inflammatory biomarkers. HF intake over time may negatively impact cardiovascular health and liver function in rats.