Sürdürülebilir Kalkınma Amaçları

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• MakaleAçık Erişim2019Scopus SJRQ2/r/bayburt/13884
  Characterization of an interesting selenium-dependent glutathione peroxidase (Se-GPx) protecting cells against environmental stress: The Camelus dromedarius erythrocytes Se-GPx

  Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Solak, Kübra; Mavi, Ahmet

  Camel lives most of its life under high environmental stress in the desert. Glutathione peroxidase plays a key role in protecting cells against oxidative stress. For the first time, selenium-dependent glutathione peroxidase (Se-GPx) was purified from camel erythrocytes, biochemically characterized, and some of its properties were studied. The enzyme was purified using ethanol-chloroform treatment, acetone precipitation and ion exchange chromatography. A purification fold of 33.72 with 0.19% yield were obtained. The native molecular weight of the enzyme was estimated to be about 69 kDa. On SDS-PAGE, the enzyme was composed of two different subunits with a molecular weight of approximately 53 and 21 kDa. An optimum temperature of 47 °C and an optimum pH of 7.2 were found. The activation energy was 41.71 kJ/mol. This enzyme was inhibited by thiol reagents, D,L-Dithiothreitol and β-Mercaptoethanol, and was sensitive to bivalent cations. The enzyme had a general specificity toward hydroperoxides, and high specificity for reduced glutathione. The purified enzyme contained 3.06 mol of selenium per mol of protein. The Km and Vmax values for hydrogen peroxide and reduced glutathione were 0.72 and 1.58 mM, and 25.33 and 31.03 U/mg, respectively. The biochemical properties of camel Se-GPx were different comparing to those of mammalian species. Lower molecular weight, heterodimeric structure, higher optimum temperature, relatively lower optimum pH, lower content of selenium and higher affinity for hydrogen peroxide at low reduced glutathione concentration, these could be explained by the fact that camel is able to live in the intense environmental stress in the desert.

  AtıfScopus11·WoS10·OpenAlex10

  İncele
• MakaleYalnız künye2019Scopus SJRQ1/r/bayburt/12483
  Purification and biochemical characterization of a novel copper, zinc superoxide dismutase from liver of camel (Camelus dromedarius): An antioxidant enzyme with unique properties

  Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Mavi, Ahmet

  A novel copper, zinc superoxide dismutase (CuZnSOD) was purified to homogeneity from the liver of an animal well adapted to the stressful living conditions of the desert, the camel (Camelus dromedarius). The biochemical properties of camel liver CuZnSOD were examined. The purified enzyme had a native molecular weight of 28 kDa, as judged by gel filtration chromatography, and showed a single band at 27 kDa on SDS-PAGE, indicating that it is a monomeric protein. Optimal activity of the purified enzyme occurred at 43 °C and pH 6.0, and the activation energy was 1.42 kJ/mol. CuZnSOD activity was strongly inhibited by β-ME, DTT, H 2 O 2 and SDS and slightly inhibited by EDTA, NaN 3 and PMSF. Al 3+ , Ca 2+ , Cd 2+ , Mg 2+ and Zn 2+ stimulated CuZnSOD activity, whereas Ba 2+ , Co 2+ , Fe 2+ and Ni 2+ inhibited it. The purified enzyme contained 0.010 µg of Cu and 0.69 µg of Zn per mg of protein. K m , V max , k cat and k cat /K m values for NBT and riboflavin were 16.27 and 0.16 µM, 20.85 and 21.54 U/mg, 9.65 and 9.97 s −1 , and 0.59 and 62.33 s -1 µM −1 , respectively. Camel liver CuZnSOD exhibited unique biochemical properties compared to those of other CuZnSODs, including lower molecular weight with a monomeric structure, higher optimum temperature, very low E a , very low optimum pH, very low contents of Cu and Zn, and higher affinity, turnover number and catalytic efficiency for riboflavin. These unique properties of camel liver CuZnSOD might be related to the ability of this animal to inhabit stressful desert conditions.

  AtıfScopus26·WoS23·OpenAlex26

  İncele
• MakaleYalnız künye2018/r/bayburt/15309
  Purıfıcatıon of protease enzyme from çiğdem (crocus bıflorus) tubers and ınvestıgatıon of usabılıty of the purıfıed protease enzyme ın coagulatıon of caseın

  Çelik, Safinur Yıldırım

  It is known that in some diseases (SARS, mad cow, pig and bird flu) that have passed from animals to humans have increased in recent years. In consumers, the use of animal proteases in the production of food products leads to concerns about the spread of these diseases. For these reasons, it has been an increase in demand for the product obtained from plant sources. The fact that only a small proportion of commercially available enzymes are herbaceous, have encouraged researchers to search for new herbal protease sources that can be used commercially. In this study, for the first time protease enzyme was purified from the tubers of a Crocus biflorus and characterized. The protease enzyme was purified 86 fold by ammonium sulfate precipitation and ion exchange chromatography. Optimum pH and temperature was found as 5.5 and 50 °C. The values of Vmax and KM were calculated as 47 mg/mL.min and 0.9 g/L, respectively. The molecular weight of the enzyme was calculated to be 35 kDa by using SDS-PAGE. It was determined that the purified enzyme can be used in the process of casein coagulation, the first step of cheese making

  AtıfTR Dizin1

  İncele
• Proje2018/r/bayburt/15180
  Sülfanilamid Bağlanmış Manyetik Nanopartiküllerle (Fe 3 O 4 @SiO 2 -PA-SA) Karbonik Anhidraz Enziminin Saflaştırması

  Çelik, Safinur; Mavi, Ahmet

  Enzimler, endüstriyel süreçlerde ve bilimsel çalışmalarda oldukça yaygın olarak kullanılmaktadır. Bu sebeple enzimlerin hızlı ve ucuz bir yolla yüksek saflıkta saflaştırılması, ekonomik bir önem arz etmektedir. Bu projede amaç, karbonik anhidraz (CA) enzimini kısa sürede yüksek verimle saflaştırmak için ucuz, tekrar kullanılabilir ve manyetik temelli yeni bir materyal geliştirmektir. Projenin birinci bölümünde ilk olarak Fe3O4 MNP sentezlenmiştir. MNP?nin kararlılığını sağlamak için ikinci basamakta tetraetilortosilikat (TEOS) kullanılarak MNP?ler silika ile kaplanmış ve Fe3O4@SiO2 elde edilmiştir. Üçüncü basamakta Fe3O4@SiO2 yüzeyine APTES ((3-Aminopropil) trietoksisilan) ile -NH2 grubu ilave edilerek Fe3O4@SiO2-NH2 üretilmiştir. Dördüncü basamakta ise Fe3O4@SiO2-NH2 yüzeyinde bulunan -NH2 ile Phloretik asitin (PA, 3-(4-hidroksifenil) propiyonik asit) -COOH grubu, EDC (N-(3- Dimetilaminopropil)-N?-etilcarbodiimid hidroklorid) ve NHS (N-hidroksi süksinimid) aktivatörlüğünde, kovalent olarak bağlanmış ve Fe3O4@SiO2-PA elde edilmiştir. Son olarak karbonik anhidraz enziminin ilgisinin bulunduğu sülfonamidin (SA) diazonyum tuzu, Fe3O4@SiO2-PA?de bulunan Phloretik asitin aromatik halkasına bağlanarak Fe3O4@SiO2- PA-SA sentezlenmiştir. Nihai partikül (Fe3O4@SiO2-PA-SA) SEM, TEM, XRD ve FT-IR ile karakterize edilmiştir. TEM analiz sonuçları, hekzagonal şekle sahip monodispers ve ortalama 10 nm boyutlarında Fe3O4 MNP?ler üretildiğini göstermektedir. Silika kaplama ve APTES modifikasyonu yapılan nanopartiküllere ait TEM görüntüleri; Fe3O4@SiO2-NH2 MNP?lerin multi-çekirdek içerdiğini, SEM görüntüleri ise MNP?lerin 100 nm?den küçük ve küresel morfolojiye sahip olduğunu göstermektedir. Projenin ikinci bölümünde Fe3O4@SiO2-PA-SA kullanılarak hemolizattan karbonik anhidraz (CA) enzimi saflaştırılmıştır. Fe3O4@SiO2-PA-SA partikülleri hemolizat ile karıştırılıp CA?nın sülfanilamite bağlanması sağlanmıştır. Daha sonra bir mıknatıs ile Fe3O4@SiO2-PA-SA:::CA partikülleri toplanarak hemolizat ortamından uzaklaştırılmıştır. Fe3O4@SiO2-PA-SA:::CA partikülleri yıkanarak safsızlıklar ortamdan uzaklaştırılmıştır. Fe3O4@SiO2-PA-SA:::CA partiküllerinin üzerine elüsyon tamponu ilave edilerek CA, partiküllerden ayrılmış ve çözelti ortamına alınmıştır. Ortamda kalan Fe3O4@SiO2-PA-SA partiküller tekrar kullanılmak üzere mıknatısla geri kazanılmıştır. Sentezlenen MNP?ler ile CA, 2 saat gibi kısa bir zamanda ve basit bir şekilde hemolizattan saflaştırılabilmiştir. MNP?lerin maksimum enzim tutma kapasitesi 19,5 ± 1,1 mg CA/g MNP olarak hesaplanmıştır. Elde edilen CA?ın SDS-PAGE ile saflığı kontrol edilmiş ve enzimin yüksek saflıkta olduğu görülmüştür. Sentezlenen MNP?leri tekrar kullanılabilirliği test edilmiş ve üç kullanıma kadar MNP?lerin etkinliğini kaybetmediği görülmüştür.

  İncele
• MakaleAçık Erişim2018/r/bayburt/14580
  Purıfıcatıon of protease enzyme from çiğdem (crocus bıflorus) tubers and ınvestıgatıon of usabılıty of the purıfıed protease enzyme ın coagulatıon of caseın

  Yıldırım Çelik, Safinur

  It is known that in some diseases (SARS, mad cow, pig and bird flu) that have passed from animals to humans have increased in recent years. In consumers, the use of animal proteases in the production of food products leads to concerns about the spread of these diseases. For these reasons, it has been an increase in demand for the product obtained from plant sources. The fact that only a small proportion of commercially available enzymes are herbaceous, have encouraged researchers to search for new herbal protease sources that can be used commercially. In this study, for the first time protease enzyme was purified from the tubers of a Crocus biflorus and characterized. The protease enzyme was purified 86 fold by ammonium sulfate precipitation and ion exchange chromatography. Optimum pH and temperature was found as 5.5 and 50 °C. The values of Vmax and KM were calculated as 47 mg/mL.min and 0.9 g/L, respectively. The molecular weight of the enzyme was calculated to be 35 kDa by using SDS-PAGE. It was determined that the purified enzyme can be used in the process of casein coagulation, the first step of cheese making.

  • 
  AtıfOpenAlex3

  İncele
• MakaleYalnız künye2018Scopus SJRQ4/r/bayburt/13849
  Partial Purification and Some Interesting Properties of Glutathione Peroxidase from Liver of Camel (Camelus dromedarius)

  Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Solak, Kübra; Mavi, Ahmet

  Climate change and increasing temperatures are global concerns. Well adapted to desert life, the camel (Camelus dromedarius) lives most of its life under high environmental stress and represents an ideal model for studying desert adaptation among mammals. Glutathione peroxidase is the principal antioxidant defense system capable of protecting cells from oxidative stress. Glutathione Peroxidase from camel liver was purified (11.64-fold purification with 1.73% yield) and characterized The molecular weight of the enzyme was estimated to be about 69 kDa by gel filtration and 34 kDa by SDS-PAGE, implying dimeric structure of the protein. An optimum temperature of 47°C and an optimum pH of 7.8 were found. This enzyme is a typical SH-enzyme that is inhibited by D,L-dithiothreitol and β-mercaptoethanol and sensitive to bivalent cations. The enzyme had common specificity toward hydroperoxides and high specificity for reduced glutathione. The Km and Vmax values for hydrogen peroxide and reduced glutathione were 0.57 and 2.10 mM and 1.11 and 0.87 U/mg, respectively. The purified enzyme contained 16 ng of selenium per mg of protein. Our results show that the camel glutathione peroxidse exhibits properties different of those reported for other mammalian species. Lower molecular weight, homodimeric structure, higher optimum temperature, relatively low optimum pH, high affinity for hydrogen peroxide at low concentration of reduced glutathione and very low content of selenium could be explained by adaptation of the camel to living in the desert under intense environmental stress.

  AtıfScopus12·WoS9·OpenAlex11

  İncele
• MakaleYalnız künye2017/r/bayburt/15380
  The In-vitro Effect of Lisonopril on Serum Alkaline Phosphatase and Acid Phosphatase Enzymes Activity

  Demir, Yaşar; Çelik, Safinur Yıldırım; Demir, Nazan

  Hypertension is a disease that most elderly people suffer. People with high blood pressure often obliged to use the drug that lowers blood pressure in order to maintain a healthy lifestyle throughout their lives. In this study, the in vitro effect of lisonopril on serum alkaline phosphatase and acid phosphatase enzymes which are essential for normal bone formation and mineralization activities was investigated. Alkaline phosphatase enzyme was purified using DEAE-cellulose, acid phosphatase enzyme was purified using CM-cellulose ion exchange chromatography from human serum. The activities of alkaline and acid phosphatase were determined using pnitrophenylphosphate as the substrate. When finding out the activity of TrACP enzyme, adding tartrate to the environment provided inhibition of other acid phosphatase enzymes than TrACP. The activities of alkaline phosphatase and acid phosphatase, which is resistant to tartrate, have been found at five different concentrations of substrates (0.033, 0.1, 0.16, 0.23 and 0.3 mm) in environment with inhibitor and without inhibitor. While three different concentrations of the inhibitor, including 10-2,10-3 and 10-4, was used for each substrate concentration. It was found that the drug inhibit both enzymes, and I50 value was calculated as 0.17 mm and 0.79 mm. Furthermore, Ki values were calculated as 6.98x10-4, 7.06x10-4 for ALP and TrACP respectively by utilizing the Lineweaver-Burk plot

  İncele
• MakaleYalnız künye2017Scopus SJRQ1/r/bayburt/12470
  Purification of camel liver catalase by zinc chelate affinity chromatography and pH gradient elution: An enzyme with interesting properties

  Chafik, Abdelbasset; Essamadi, Abdelkhalid; Çelik, Safinur Yildirim; Mavi, Ahmet

  Climate change and increasing temperatures are global concerns. Camel (Camelus dromedarius) lives most of its life under high environmental stress in the desert and represent ideal model for studying desert adaptation among mammals. Catalase plays a key role in protecting cells against oxidative stress. For the first time, catalase from camel liver was purified to homogeneity by zinc chelate affinity chromatography using pH gradient elution, a better separation was obtained. A purification fold of 201.81 with 1.17% yield and a high specific activity of 1132539.37 U/mg were obtained. The native enzyme had a molecular weight of 268 kDa and was composed of four subunits of equal size (65 kDa). The enzyme showed optimal activity at a temperature of 45 °C and pH 7.2. Thiol reagents, β-Mercaptoethanol and D,L-Dithiothreitol, inhibited the enzyme activity. The enzyme was inhibited by Al3+, Cd2+ and Mg2+, whereas Ca2+, Co2+ and Ni2+ stimulated the catalase activity. Reduced glutathione has no effect on catalase activity. The Km and Vmax of the enzyme for hydrogen peroxide were 37.31 mM and 6185157 U/mg, respectively. Sodium azide inhibited the enzyme noncompetitively with Ki value of 14.43 μM, the IC50 was found to be 16.71 μM. The properties of camel catalase were different comparing to those of mammalian species. Relatively higher molecular weight, higher optimum temperature, protection of reduced glutathione from hydrogen peroxide oxidation and higher affinity for hydrogen peroxide and sodium azide, these could be explained by the fact that camel is able to live in the intense environmental stress in the desert.

  AtıfScopus9·WoS9·OpenAlex10

  İncele
• MakaleYalnız künye2015/r/bayburt/15488
  Agrobacterium radiobacter'den Pektin Liyaz Enziminin Üretilmesi, Saflaştırılması, Karakterize Edilip Meyve Suyu Üretiminde Kullanılması

  Barış, Özlem; Demir, Yaşar; Yıldırım Çelik, Safinur; Demir, Nazan; Güllüce, Medine

  Ekstraselüler pektin liyaz enzimi (EC 4.2.2.10) Agrobacterium radiobacter'den katı ortam fermantasyonu ile üretilmiş ve DEAE-selüloz iyon değişim kromatografisi kullanılarak 21 kat saflaştırılıp karakterize edilmiştir. Enzimin molekül ağırlığı Sephadex G-100 jel filtrasyon kromatografisi ile 67 kDa olarak bulunmuş ve enzimin saflığı SDS-PAGE ile kontrol edilmiştir. Enzimin optimum pH'sı ve sıcaklığı sırasıyla 8 ve 60°C olarak belirlenmiştir. Enzim aktivitesinin 24 saat boyunca kararlı olduğu en yüksek sıcaklığın 40°C'de olduğu gözlenmiştir. 50°C'de yaklaşık 4 saat boyunca, 60°C'de ise 1 saat boyunca %50 aktivitesini koruduğu bulunmuştur. Saflaştırılan enzimin Vmax ve KM'si Lineweaver-Burk grafiği kullanılarak 4.36 mg/mL and 303 µmol/L.dakika olarak hesaplanmıştır. Pektin liyaz enziminin aktivitesi üzerine metal iyonlarının etkisi incelenmiş ve Mg2+ ve Ca2+ iyonlarının enzimi kısmen, Fe3+, Zn2+, Cu2+ ve Hg2+ iyonlarının enzimi tamamen inhibe ettiği anlaşılmıştır. Co2+ (0,1 mM, 1 mM ve 10 mM) iyonunun ise enzimin az da olsa aktivitesini arttırdığı gözlenmiştir. Saflaştırılıp karakterize edilen enzim meyve suyu üretiminde kullanıldığında kontrole göre meyve suyu veriminde önemli artış görülmüştür.

  İncele
• MakaleAçık Erişim2014/r/bayburt/14147
  Production of pectin lyase from Geobacillus pallidus p26, purification, characterization and fruit juice application

  Çelik, Safinur Yildirim; Demir, Nazan; Demir, Yasar; Adiguzel, Ahmet; Gulluce, Medine

  A bacterial strain was isolated from Pasinler hot spring, Erzurum, Turkey. The purified thermophilic isolate was identified as Geobacillus pallidus P26 and used to produce extracellular pectin lyase (EC 4.2.2.10). Pectin lyase enzyme was purified 34 fold by using DEAE-cellulose anion exchange column chromatography and characterized. Molecular weight of the enzyme was determined as 56 kDa by using Sephadex G-100 gel filtration chromatography. Purification of enzyme was verified by SDS-PAGE. The pH- and temperature optima of enzyme were determined (pH 9.0 and 60 degrees C, respectively). Pectin lyase was mostly stable at 50 degrees C: for 24 hours. Its' activity ducruitscd to 50 % for 24 h at 60 degrees C. K-M and V-max were calculated as 24.8 mg/mL and 2.28 mu mol/L min, respectively. Purified pectin lyase was inhibited by Fe3+, Zn2+, Cu2+, Ca2+, Co2+ and Hg2+ but not by Mg2+. The purified pectin lyase enzyme was used for getting fruits juices. It was found that yields of fruits juices increased when they were compared with control.

  AtıfWoS9·OpenAlex9

  İncele