Effect of CO, NOx and SO2 on ROS production, photosynthesis and ascorbate-glutathione pathway to induce Fragaria×annasa as a hyperaccumulator.

A study was conducted to determine the effect of carbon monoxide (CO), nitroxide (NOx) and sulfur dioxide (SO2) on ROS production, photosynthesis and ascorbate-glutathione pathway in strawberry plants. The results showed that both singlet oxygen (O2(-1)) and hydrogen peroxide (H2O2) content increased in CO, NOx and SO2 treated strawberry leaves. A drastic reduction of primary metabolism of plants (photosynthesis), with the closure of stomata, resulted in a reduction of protein, carbohydrate and sucrose content due to production of reactive oxygen species (ROS) under prolonged exposure of gas stress.

Isolation and characterization of N-acylhomoserine lactonase from the thermophilic bacterium, Geobacillus caldoxylosilyticus YS-8.

Geobacillus caldoxylosilyticus YS-8, which was isolated from volcanic soil in Indonesia, was found to degrade various N-acylhomoserine lactones (AHLs) with different lengths and acyl side-chain substitutions over a wide temperature range of 30-70 °C. The purified AHL-degrading enzyme showed a single band of 32 kDa, and its N-terminal amino acid sequence was determined to be ANVIKARPKLYVMDN, tentatively suggesting that the AHL-degrading enzyme was AHL lactonase. The AHL-degrading activity of the purified enzyme was maximized at pH 7.