Browsing by Subject "Purification"

Now showing 1 - 3 of 3

Open Access
Expression and purification of the hepatitis C virus core protein in Ecoli and testing of human sera with this core antigen
(1998) Eroğlu, Çağla
The hepatitis C virus (HCV) infection is an important cause of morbidity and mortality world wide. Infection with HCV becomes chronic in more than 80% of the cases and it accounts for 20%of all cases of acute hepatitis. Hepatitis C virus was first identified by the molecular cloning of the virus genome in 1989. It is an enveloped, positive strand RNA virus with a genome size of around 9.5 Idlobases. The single stranded RNA genome of the virus contains a large open reading frame codes for a large poly-protein of 3,010 to 3,033 amino acids which is shown to be processed by a combination of host and viral proteinases to produce at least ten proteins post-translationally. The proteins that are closer to the amino terminal of the poly-protein are termed as structural and the rest closer to the carboxy terminal are called non-structural (NS) proteins. The core protein is the putative nucleocapsid component of the virion, and it is highly basic in nature. Core protein is the most highly conserved region of the hepatitis C virus open reading frame and it is shown to be highly immunogenic. Also, as the core protein is the putative capsid protein of the hepatitis C virus, antibodies against core antigen most probably arise much earlier than the antibodies against nonstructural proteins. In this study, the core protein of the hepatitis C virus was cloned, expressed and purified in order to establish an ELISA system to test the human sera with this viral antigen. It was shown that in 86% of the patients, diagnosed previously with the third generation enzyme immunoassays to be infected with hepatitis C, have antibodies against this core antigen. The core antigen gave no false positive results when tested with the negative control samples which were found to be Anti-HCV negative previously.
Open Access
A highly sensitive and specific enzyme-linked immunosorbent assay of antibodies to hepatitis C virus
(2000) Eroğlu, C.; Yıldız, E.; Öztürk, M.; Pınarbaşı, E.
In this study, a 178 amino acids long portion of the hepatitis C virus (HCV) core gene was cloned, sequenced, expressed in Escherichia coli, and purified. The resulting antigen (C178) was tested with human sera enzyme-linked immunosorbent assay (ELISA) in order to assess its ability to diagnose HCV. It was shown by ELISA that 92% of the patients sera, diagnosed previously by a 3(rd) generation enzyme immunoassay (EIA) as HCV-positive, had antibodies against the C178 antigen. This antigen gave no false positive results when tested with anti-HCV-negative sera.
Open Access
Identification of relative protein bands in Polyacrylamide Gel Electrophoresis (PAGE) using multiresolution snake algorithm
(IEEE, 1998-10) Gürcan, Metin Nafi; Koyutürk, Mehmet; Yıldız, H. Serkan; Çetin Atalay, Rengül; Çetin, A. Enis
Polyacrylamide Gel Electrophoresis (PAGE) is one of the most widely used techniques in protein research. In the protein purification process, it is important to determine the efficiency of each purification step in terms of percentage of protein of interest found in the protein mixture. This study provides a rapid and reliable way to determine this percentage. The region of interest containing the protein is detected using the snake algorithm. The iterative snake algorithm is implemented in a multiresolutional framework. The snake is initialized on a low resolution image. Then, the final position of the snake at low resolution is used as the initial position in the higher resolution image. Finally, tile area of the protein is estimated as the area enclosed by the final position of the snake.