Oztetik, Elif
İşcan, Mesude
Glutathione S-transferases (GST, E.C. are generally dimeric and multifunctional enzyme family which catalyse the nucleophilic attack of the glutathione on lipophilic compounds with electrophilic centres. Since the 70's GSTs in plant species have been intensively studied, as their role discovered in herbicide detoxification. However, there is only a limited number of studies considering the GST enzyme composition from forest trees, especially not in Pinus brutia, Ten. The trees that exhibited healthy appearance were selected and all belong to the same altitude profile which is located in METU / Yalincak area (Ankara, Turkey). GST activities in the supernatant fractions prepared from needles of P.brutia were determined spectrophotometrically by using 1-chloro-2,4-dinitrobenzene, 2,3-dichloro-4-(2-methylene butyryl)-phenoxy acetic acid (ethacrynic acid), 1,2-dichloro-4-nitrobenzene, 1,2-epoxy-3-(p-nitrophenoxy) propane and p-nitrobenzyl chloride as substrates. Only 1-chloro-2,4-dinitrobenzene (160 +/- 10 nmoles min(-1) mg(-1)) and 1,2-dichloro-4-nitrobenzene (2.30 +/- 0.38 nmoles min(-1) mg(-1)) activities were detected and the rest were found as negligible. Accordingly, during purification of GSTs from needles of P.brutia, 1-chloro-2,4-dinitrobenzene was used as the substrate. Purification of GSTs was performed by sequential application of supernatant to gel filtration column chromatography on Sephadex G-25, anion exchange diethylaminoethyl cellulose column chromatography and S-hexylglutathione agarose affinity chromatography. After the final step of purification procedure, 1-chloro-2,4-dinitrobenzene conjugating activity of P. brutia cytosolic GSTs was purified about 15.45 fold with 1.95% yield. Sodium dodecyl sulfate polyacrylamide gel electophoresis results showed that the purified GST isozyme had an Mr of 24 kDa. With this study, we report for the first time the GST isozymes in a gymnosperm, P. brutia.


Purification of glutathione S-transferases and genetic characterization of Zeta isozyme from Pinus brutia, Ten
Öztetik, Elif; İşcan, Mesude; Department of Biochemistry (2005)
Glutathione S-transferases (GST, EC2.5.1.18) are a family of multifunctional, dimeric enzymes that catalyse the nucleophilic attack of the tripeptide glutathione (?-L-glutamyl-L-cysteinyl-L-glycine) on lipophilic compounds with electrophilic centres. The primary function of GSTs is generally considered to be the detoxification of both endogenous and xenobiotic compounds. Cytosolic GSTs have been grouped into eleven distinct classes as: (A); Alpha, (M); Mu, (P); Pi, (S); Sigma, (T); Theta, (Z); Zeta, (F); Ph...
Characterization and modulation by drugs of sheep liver microsomal flavin monooxygenase activity
Demirdöǧen, Birsen Can; Adalı, Orhan (Wiley, 2005-07-01)
The flavin monooxygenases (FMO) catalyse the NADPH and oxygen-dependent oxidation of a wide range of nucleophilic nitrogen-, sulfur-, phosphorus-, and selenium heteroatom-containing chemicals, drugs, and agricultural agents. In the present study, sheep liver microsomal FMO activity was determined by measuring the S-oxidation rate of methimazole and the average specific activity obtained from different microsomal preparations was found to be 3.8 +/- 1.5 nmol methimazole oxidized min(-1) mg(-1) microsomal pro...
Analysis of the genetic determinant for production of the pediocin P of Pediococcus pentosaecus Pep 1
Osmanagaoglu, O; Beyatli, Y; Gündüz, Ufuk; Sacilik, SC (2000-01-01)
Pediococcus pentosaceus Pep1 is a vacuum-packaged Turkish sausage isolate which produces a potentially novel bacteriocin of the pediocin (anti-Listeria) family of peptides designated as pediocin P. Curing experiments and plasmid profile analysis indicated that both bacteriocin immunity and production determinants were linked and encoded by 9.0 MDa plasmid, pHD1.0. Attempts to transform purified plasmid pHD1.0 into recipient Escherichia coli JM109 cells by electroporation were successful but none of the E. c...
Investigation for natural extract inhibitors of bovine lens aldose reductase responsible for the formation of diabetis dependent cataract
Onay, Melih; Çoruh, Nursen; Department of Biochemistry (2008)
In the polyol pathway, Aldose reductase (AR) is an important enzyme in reduction of aldehydes and aldosugars to their suitable alcohols. AR, using NADPH as a coenzyme, has a molecular weight of 37 000 dalton. AR in its activated form, known to increase the sorbitol accumulation in lens, is responsible for the cataract formation in diabetis diseases. Therefore, the inhibition of aldose reductase is important to prevent the incedence of cataract formation in diabetus mellitus. In the treatment of diabetis dep...
Preparation and Characterization of Mixed Halide MAPbI(3-x)Cl(x) Perovskite Thin Films by Three-Source Vacuum Deposition
Babaei, Azin; Soltanpoor, Wiria; Tesa-Serrate, Maria A.; Yerci, Selçuk; Sessolo, Michele; Bolink, Henk J. (2020-04-01)
Chloride is extensively used in the preparation of metal halide perovskites such as methylammonium lead iodide (MAPbI(3-x)Cl(x)), but its persistence and role in solution-processed materials has not yet been rationalized. Multiple-source vacuum deposition of perovskites enables a fine control over thin-film stoichiometry and allows the incorporation of chemical species irrespective of their solubility. Herein, the first example of mixed MAPbI(3-x)Cl(x) thin films prepared by three-source vacuum deposition i...
Citation Formats
E. Oztetik and M. İşcan, “CHARACTERIZATION OF GLUTATHIONE S-TRANSFERASES FROM NEEDLES OF Pinus brutia Ten. TREES,” FRESENIUS ENVIRONMENTAL BULLETIN, pp. 516–523, 2013, Accessed: 00, 2020. [Online]. Available: