Carbenicillin and cefotaxime, two antibiotics commonly used for excluding Agrobacterium tumefaciens during plant transformation, were tested for their bacteriostatic effects as well as for their effects on plant regeneration in adventitious root explants of papaya following co-culture with Agrobacterium. A washing step with sterilized distilled water two days after co-culture enhanced the bacte...

The present study was carried out to evaluate the effects of light and plant growth regulators on callus induction and explant browning in date palm cultivar, Estameran in in vitro condition. The explants were pretreated by an antioxidant combination (100 mgl-1 citric acid and 150 mgl-1 ascorbic acid) for 3 days in 5 °C. Then, the  leaf explants  were cultured in Murashige and Skoog medium (MS)...

For the determination of dissolved oxygen, working principle of the fiber optic oxygen sensor is studied. The sensor system calibration method and temperature compensation measures and their maintenance methods are analyzed. The dissolved oxygen sensors current widely using oxygen electrode and optical fiber oxygen sensor are compared. Optical fiber probe sensor is used in the current system, t...

To investigate bioturbation effects on cadmium (Cd) fluxes from overlying water to sediments, indoor microcosms were developed. The bioturbating organisms were freshwater tubificid worms. Three experimental conditions were studied during 56 d. The three conditions were contaminated water column ([Cd]: 20 microg/L) with or without worms and uncontaminated water column with worms. Cadmium vertica...

The present study was conducted to examine the contamination of rivulet situated at Kasimpur, Aligarh (27.218° N; 79.378° E). It receives the wastewater of Harduaganj Thermal Power Plant (HTPS) containing fly ash and heavy metals. Among the heavy metals estimated in the rivulet water, Fe (8.71 mgL(-1)) was present in the highest concentration followed by Cu (0.86 mgL(-1)), Zn (0.30 mgL(-1)) Mn ...

Three genes, mgl A, B, and C, are required for active transport of substrate by the methylgalactose permease of E. coli K12. We report here that only two of these genes are required for substrate translocation, as seen by the ability or inability of isogenic mgl mutants (referred to as Tra+ and Tra minus, respectively) to grow on methyl-beta-D-galactopyranoside, supplied as sole carbon source. ...

the physico-chemical parameters, nutrient status and heavy metal ions of huluka and alaltu rivers of ambo, ethiopia were studied. temperature, ph, electrical conductivity, co2 content, total dissolved solids, hardness, dissolved oxygen, ca2+, mg2+, cl-, nitrate, phosphate and sulphate have been determined along with selected heavy metals to assess the various water quality profiles along the ri...

The effect of operating conditions during molinate degradation by the defined mixed bacterial culture DC, previously described as able to mineralize molinate, was evaluated in a batch reactor. Parameters such as the rate of molinate degradation, the dissolved organic carbon (DOC) consumption and the accumulation of molinate degradation products were monitored along the culture growth. The effec...

L-Methionine gamma-lyase (MGL) catalyzes the pyridoxal 5'-phosphate (PLP) dependent alpha,gamma-elimination of L-methionine. We have determined two crystal structures of MGL from Pseudomonas putida using MAD (multiwavelength anomalous diffraction) and molecular replacement methods. The structures have been refined to an R-factor of 21.1% at 2.0 and 1.7 A resolution using synchrotron radiation d...

This study investigated the influence of dissolved oxygen concentration and aeration time on nitrification and nitrite accumulation in an attempt to optimize the recently developed biological-partial-nitritation process for the treatment of strong nitrogen wastewaters. Investigation of dissolved oxygen concentration on ammonium and nitrite oxidation was carried out in a batch reactor. The disso...