Effects of Various Inhibitors on β-galactosidase Purified from the Thermoacidophilic Alicyclobacillus acidocaldarius Subsp. Rittmannii Isolated from Antarctica

Reyhan Gul Guven,Alevcan Kaplan,Kemal Guven,Fatma Matpan,Mehmet Dogru 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.1

β-Galactosidase purified from the thermoacidophilic Alicyclobacillus acidocaldarius subsp. rittmannii isolated from Antarctica is a member of the GH42 family. The enzyme was not effected by various concentrations of its reaction product glucose, but was greatly inhibited by the other reaction product galactose using both substrates,ONPG and lactose. Linewever-Burk plot analysis derived from both ONPG and lactose hydrolysis results showed that galactose is a mixed-type inhibitor of the purified β-galactosidase. The enzyme was slightly activated by Mg^(2+)(13% at 20 mM), while inhibited at higher concentrations of Ca^(+2) (33% at 10 mM), Zn^(+2) (86% at 8 mM) and Cu^(+2)(87% at 4 mM). The enzyme activity was not significantly altered by the metal ion chelators EDTA and 1,10-phenanthroline up to 20 mM, indicating that this enzyme is not a metalloenzyme. 2-Mercaptoethanol and DTT were found to enhance β-galactosidase activity, while p-chloromercuribenzoic acid (PCMB) completely inhibited enzymatic activity (97% at 1 mM; 99.7% at 2 mM), indicating at least one essential Cys residue modified by the reagents in the active site of β-galactosidase. Iodoacetamide and Nethylmaleimide had little effect on the β-galactosidase. Phenylmethylsulfonyl fluoride (PMSF) inhibited the enzyme strongly (19.8% at 1 mM; 71.9% at 10 mM), also showing the participation of serine for enzyme activity.

Protective Effects of the Nuclear Factor Kappa B Inhibitor Pyrrolidine Dithiocarbamate on Experimental Testicular Torsion and Detorsion Injury

Kabay, Sahin,Ozden, Hilmi,Guven, Gul,Burukoglu, Dilek,Ustuner, Mehmet Cengiz,Topal, Fatma,Gunes, Hasan Veysi,Ustuner, Derya,Ozbayer, Cansu The Korean Society of Pharmacology 2014 The Korean Journal of Physiology & Pharmacology Vol.18 No.4

Testicular torsion results with the damage of the testis and it is a surgical emergency. Pyrrolidine dithiocarbamate (PDTC) is a low-molecular-weight antioxidant and potent inhibitor of nuclear factor kappa B (NF-${\kappa}B$) activation. In this study, we aimed to investigate the effects of PDTC to testicular torsion-detorsion (T/D) injury. Forty adult male Sprague-Dawley rats were separated into four groups. A sham operation was performed in group I. In group II, torsion is performed 2 hours by 720 degree extravaginally testis. In group III, 4 h reperfusion of the testis was performed after 2 h of testicular torsion. In group IV, after performing the same surgical procedures as in group III, PDTC (100 mg/kg, intravenous's) was administered before 30 min of detorsion. The testes tissue malondialdehyde (MDA), superoxide dismutase (SOD) catalase (CAT) level was evaluated. Histological evaluations were performed after hematoxylin and eosin staining. Testicular tissue MDA levels were the highest in the T/D groups compared with treatment group. Administration of PDTC prevented a further increase in MDA levels. Significant decrease occurred in CAT and SOD levels in treatment group compared with the control group. The rats in the treatment group had normal testicular architecture. The results suggest that PDTC can be a potential protective agent for preventing the biochemical and histological changes related to oxidative stress in testicular injury caused by testis torsion.

Protective Effects of the Nuclear Factor Kappa B Inhibitor Pyrrolidine Dithiocarbamate on Experimental Testicular Torsion and Detorsion Injury

Sahin Kabay,Hilmi Ozden,Gul Guven,Dilek Burukoglu,Mehmet Cengiz Ustuner,Fatma Topal,Hasan Veysi Gunes,Derya Ustuner,Cansu Ozbayer 대한약리학회 2014 The Korean Journal of Physiology & Pharmacology Vol.18 No.4

Testicular torsion results with the damage of the testis and it is a surgical emergency. Pyrrolidinedithiocarbamate (PDTC) is a low-molecular-weight antioxidant and potent inhibitor of nuclear factorkappa B (NF-κB) activation. In this study, we aimed to investigate the effects of PDTC to testiculartorsion-detorsion (T/D) injury. Forty adult male Sprague-Dawley rats were separated into four groups. A sham operation was performed in group I. In group II, torsion is performed 2 hours by 720 degreeextravaginally testis. In group III, 4 h reperfusion of the testis was performed after 2 h of testiculartorsion. In group IV, after performing the same surgical procedures as in group III, PDTC (100 mg/kg,intravenous’s) was administered before 30 min of detorsion. The testes tissue malondialdehyde (MDA),superoxide dismutase (SOD) catalase (CAT) level was evaluated. Histological evaluations were performedafter hematoxylin and eosin staining. Testicular tissue MDA levels were the highest in theT/D groups compared with treatment group. Administration of PDTC prevented a further increase inMDA levels. Significant decrease occurred in CAT and SOD levels in treatment group compared withthe control group. The rats in the treatment group had normal testicular architecture. The resultssuggest that PDTC can be a potential protective agent for preventing the biochemical and histologicalchanges related to oxidative stress in testicular injury caused by testis torsion.

Hydrogen Peroxide Extends Postharvest Life of Ctenanthe setosa Leaf Cuts under Osmotic Stress by Reducing Leaf Rolling

Aykut Saglam,Ebru Kalaycioglu,Funda Gul Guven,Neslihan Saruhan,Asım Kadioglu,Mehmet Demiralay 한국원예학회 2014 Horticulture, Environment, and Biotechnology Vol.55 No.4

Reducing effects of exogenous hydrogen peroxide on leaf rolling in detached leaves of Ctenanthe setosawere studied. The leaves were kept in H2O2 solutions ranging from 0 to 1 mM for 48 h and then, osmotic stresswas applied for 4 h by polyethylene glycol (PEG). Degree of leaf rolling, loss of leaf water, and malondialdehyde(MDA) content were reduced by 0.2 mM H2O2. Antioxidant enzymes were induced by 0.2 mM H2O2. EndogenousH2O2 content was increased after the 0.5 and 1 mM H2O2 treatments but was decreased after 0.2 mM H2O2 treatment. Proline was decreased after exogenous H2O2 applications. Total soluble sugar content was increased as compared tothe control after 0.2 mM H2O2 treatment. In conclusion, low-dose exogenous H2O2 treatment could delay leaf rollingby inducing tolerance to osmotic stress due to modulation of the antioxidant system, soluble sugar accumulation, andmaintenance of leaf hydration. Therefore, postharvest life of C. setosa cut foliage could be extended by 0.2 mMH2O2 treatments.

The electrical conductivity properties of polythiophene/TiO2 nanocomposites prepared in the presence of surfactants

Aysegul Uygun,Orhan Turkoglu,Songul Sen,Ersay Ersoy,Ayse Gul Yavuz,Gokhan Guven Batir 한국물리학회 2009 Current Applied Physics Vol.9 No.4

A composite of polythiophene (PT) and nano-titanium dioxide (TiO2), possessing core–shell structure, was synthesized via oxidative polymerization of thiophene using FeCl3 in the presence of three different surfactants: anionic, cationic, and nonionic. The morphology of the obtained composite materials was investigated by SEM, proving the core–shell structure of the prepared nanocomposite. The formation and thermal stability of the PT onto TiO2 nanoparticles were confirmed by FTIR and TGA analyses, respectively. XRD data show all of composite materials were amorphous structures. The electrical properties of the nanocomposites were investigated in the presence of surfactant materials, and the best semiconductor property was observed for PT/TiO2-anionic system. This difference in the conductivity has been attributed to differences in the stability of the composites. A composite of polythiophene (PT) and nano-titanium dioxide (TiO2), possessing core–shell structure, was synthesized via oxidative polymerization of thiophene using FeCl3 in the presence of three different surfactants: anionic, cationic, and nonionic. The morphology of the obtained composite materials was investigated by SEM, proving the core–shell structure of the prepared nanocomposite. The formation and thermal stability of the PT onto TiO2 nanoparticles were confirmed by FTIR and TGA analyses, respectively. XRD data show all of composite materials were amorphous structures. The electrical properties of the nanocomposites were investigated in the presence of surfactant materials, and the best semiconductor property was observed for PT/TiO2-anionic system. This difference in the conductivity has been attributed to differences in the stability of the composites.