Sunflower seed lipase: extraction, purification, and characterization

A simple procedure for the extraction of the lipolytic activity from sunflower seed has been developed. Various conditions of extraction have been optimized in order to obtain maximum yield of lipase. A new lipase enzyme was purified by the fractional salt precipitation from the supernatant, dialysis on a cellulose membrane, and gel column chromatography on Sephadex G-75. The lipase was monomeric, with an apparent Mr of 22 kDa and a pI of 8, with the electrophoretic analysis. Kinetics of the enzyme activity versus substrate concentration showed typical lipase behavior, with Km and Vmax, values of 1.33 mM and 555 U/mg. All triglycerides were efficiently hydrolyzed by the enzyme, but this showed a preference towards triglycerides of natural mono unsaturated fatty acids. The optimum temperature, pH, and incubation time for lipolytic activity were 50 degrees C, 7.5, and 5 min, respectively. The stability of the sunflower lipase was investigated under operational and storage conditions. It was found that this enzyme preserved its lipolytic activity at temperatures between at 35-50 degrees C, alkaline pH, and for a period of about four months.     

The novel ETS factor TEL2 cooperates with Myc in B lymphomagenesis

The human ETS family gene TEL2/ETV7 is highly homologous to TEL1/ETV6, a frequent target of chromosome translocations in human leukemia and specific solid tumors. Here we report that TEL2 augments the proliferation and survival of normal mouse B cells and dramatically accelerates lymphoma development in Emu-Myc transgenic mice. Nonetheless, inactivation of the p53 pathway was a hallmark of all TEL2/Emu-Myc lymphomas, indicating that TEL2 expression alone is insufficient to bypass this apoptotic checkpoint. Although TEL2 is infrequently up-regulated in human sporadic Burkitt's lymphoma, analysis of pediatric B-cell acute lymphocytic leukemia (B-ALL) samples showed increased coexpression of TEL2 and MYC and/or MYCN in over one-third of B-ALL patients. Therefore, TEL2 and MYC also appear to cooperate in provoking a cadre of human B-cell malignancies.     

In vitro labeling of hydroxyapatite minerals by an engineered protein

Biological and biomimetic synthesis of inorganics have been a major focus in hard tissue engineering as well as in green processing of advanced materials. Among the minerals formed by organisms, calcium phosphate mineralization is studied extensively to understand the formation of mineral-rich tissues. Herein, we report an engineered fusion protein that not only targets calcium phosphate minerals but also allows monitoring of biomineralization. To produce the bi-functional fusion protein, nucleotide sequence encoding combinatorially selected hydroxyapatite-binding peptides (HABP) was genetically linked to the 3' end of the open reading frame of green fluorescence protein (GFPuv) and successfully expressed in Escherichia coli. The fluorescence and binding activities of the bi-functional proteins were characterized by, respectively, using fluorescence microscopy and quartz crystal microbalance spectroscopy. The utility of GFPuv-HABP fusion protein was assessed for both time-wise monitoring of mineralization and the visualization of the mineralized tissues. We used an alkaline phosphatase-based reaction to control phosphate release, thereby mimicking biological processes, to monitor calcium phosphate mineralization. The increase in mineral amount was observed using the fusion protein at different time points. GFPuv-HABP1 was also used for efficient fluorescence labeling of mineralized regions on the extracted human incisors. Our results demonstrate a simple and versatile application of inorganic-binding peptides conjugated with bioluminescence proteins as bi-functional bioimaging molecular probes that target mineralization, and which can be employed to a wide range of biomimetic processing and cell-free tissue engineering.     

Immobilization of lipases on different carriers and their use in synthesis of pentyl isovalerates

Porcine pancreatic lipase (PPL) and Candida cylindracea lipase (CCL) were immobilized on Celite and Amberlite IRA 938 by deposition from the aqueous solution by the addition of hexane. The influence of the immobilization on the activities of the immobilized lipase derivatives has been studied. The immobilized lipases were used in synthesis of pentyl isovalerates. Various reaction parameters affecting the synthesis of pentyl isovalerates were investigated. The reaction rates were compared with the rates of esterification with free lipases. The immobilized lipases were found to be very effective in the esterification reaction. The lipases immobilized on Celite 545 exhibited better operational stabilities than that of immobilized on Amberlite IRA-938.     

Effect of Inoculation with Non-indigenous and Indigenous Rhizobacteria of Erzurum (Turkey) Origin on Growth and Yield of Spring Barley

Two experiments were performed to examine the effects of inoculation of barley cv. Tokak 157/37 with indigenous and non-indigenous bacterial strains. A greenhouse experiment was carried out with 75 strains isolated from Erzurum Plain and Pasinler Plain soils of Turkey, and the 6 non-indigenous strains. The 41 strains had significant positive effects on tiller number per plant, 8 strains on plant height, one strain on dry matter yield, and 24 strains on plant protein concentration. In the second experiment, the response of barley to 20 treatments (9 indigenous strains, 6 non-indigenous strains, 4 levels of N, and a control) was investigated in Erzurum Agricultural Experiment field in 2000 and 2001. Inoculation with certain indigenous and non-indigenous strains clearly benefited growth and increased the yield of field grown barley. On average of years, inoculation with Strain No. 19, Strain No. 39, Strain No. 73, Strain No. 82, BA-7, BA-142 and M-13 increased total biomass by 29.4–15.1%, grain yield by 26.6–17.7%, and total N-yield by 32.7–20.6%, as compared to the control. Indigenous Strain No. 19 was superior to all other treatments in terms of grain yield and N-yields. The higher efficacy of combining Strain No. 19 and Tokak 157/37 indicates the possibility of improved associations using olden and common cultivar and indigenous bacteria. In conclusion, Strain No. 19 seems to be suitable inoculant for barley cultivation in areas such as in Erzurum conditions.     

Serum zinc levels and zinc binding capacity in thalassemia

Recently, it has been reported that serum zinc binding capacity (ZnBC) is a very important criterion to evaluate body zinc (Zn) status. It has been shown that chronic Zn deficiency occur in the patients with thalassemia major (TM). Zn deficiency in TM may cause hyperzincuria, high ferritin levels, hepatic iron load, hepatic dysfunction. This study was undertaken to determine serum Zn levels and ZnBC in different thalassemia forms and sickle cell disease (SCD). The study has been carried out on 30 Thalassemia Major (TM), 34 Thalassemia Intermedia (TI), 31 Thalassemia Trait (TT) and 10 SCD. As control group,13 healthy children and 20 adults were included. Serum Zn and ZnBC were determined by atomic absorption, then saturation index (SI%: serum Zn/ZnBC x 100) was calculated. Serum Zn levels in all patients were lower than control (p < 0.01). Serum ZnBC was at a normal level in patients with TT and TI but it was found to be lower in TM and SCD than control (p < 0.01). While serum Zn levels decrease and ZnBC increase in nutritionaL Zn deficiency, serum Zn levels decrease but ZnBC doesn't increase in patients with thalassemia.