Evaluation use of bioaugmentation and biostimulation to improve degradation of sulfolane in artificial groundwater.

Column systems were used to evaluate the effectiveness of different bioremediation methods (biostimulation (BS) and bioaugmentation (BA)) in treating sulfolane-contaminated groundwater. Batch test results confirmed that Cupriavidus sp. Y9 (Y9) was the most effective strain for BA. The optimal ratio of added native bacteria to Y9 was 10:3. The BA column adapted to a high sulfolane concentration (150 mg L-1) more rapidly and had higher sulfolane removal efficiency (90%) than did the BS column. The change in the biotoxicity of sulfolane-contaminated groundwater upon bioremediation, according to a Microtox test, revealed decreases in the inhibition of the passing of light by the BS column and BS + BA column of 38% and 63%, respectively. These results reveal that combining BS with BA can reduce the biotoxicity of sulfolane. The column tests confirmed the most effective added bacterium in BA, the operating conditions for high-efficiency bioremediation, and possible problems in its future application. The results provide an important reference for the design of methods for the remediation of contaminated sites.

Critical factors for enhancing the bioremediation of a toxic pollutant at high concentrations in groundwater: Toxicity evaluation, degrader tolerance, and microbial community.

Groundwater near refinery and natural gas plants often contain elevated concentrations of toxic sulfolane. Studies on any concentration of sulfolane are limited. Column experiment was conducted to investigate the effects of adding a low dose of H2O2 and nutrient on bioremediation. Vibrio fischeri light inhibition test was used evaluate the toxicity of effluents. The continuous column experiment conditions were sulfolane at 100 mg L-1, dissolved oxygen at 7 mg L-1, absence of phosphorus, and very short hydraulic retention time (7.9 h). A low dose of H2O2 (5.88 mM) enhanced the sulfolane (27.1%) and COD removal (11.8%) in comparison with the control set. Adding nutrient increased bicinchoninic acid protein assay levels, sulfolane removal (99.6%) and COD removal (80.3%). Addition of both H2O2 and nutrient further improved COD removal (90.3%) and COD/sulfolane ratio (0.90) and toxicity removal (Vibrio fischeri light inhibition ratio < 1%). Batch experiment indicated the degraders tolerated sulfolane up to 400 mg L-1. The DGGE method and dendrogram analysis were utilized to investigate the changes of degrader community structure.

Mono-ADP-ribosylation of histone 3 at arginine-117 promotes proliferation through its interaction with P300.

Relatively little attention has been paid to ADP-ribosylated modifications of histones, especially to mono-ADP-ribosylation. As an increasing number of mono-ADP-ribosyltransferases have been identified in recent studies, the functions of mono-ADP-ribosylated proteins have aroused research interest. In particular, histones are substrates of some mono-ADP-ribosyltransferases and mono-ADP-ribosylated histone have been detected in physiological or pathological processes. In this research, arginine-117 (Arg-117; R-117) of hsitone3(H3) is identified as the a site of mono-ADP-ribosylation in colon carcinoma(the first such site to be identified); this posttranslational modification may promote the proliferation of colon carcinoma cells in vitro and in vivo. Using a point-mutant lentivirus transfection and using an activator of P300 allowed us to observe the mono-ADP-ribosylation at H3R117 and enhancement of the activity of P300 to up-regulate the level of acetylated ß-catenin, which could increase the expression of c-myc and cyclin D1.