Moleküler Biyoloji ve Genetik Bölümü
http://hdl.handle.net/20.500.11787/60
Moleküler Biyoloji ve Genetik Bölümünü içerir.2024-03-29T06:00:26ZExpression profile of genes associated with the accumulation of triacylglycerol (TAG) in Auxenochlorella protothecoides KP7 under alkaline pH and nitrogen starvation conditions
http://hdl.handle.net/20.500.11787/8377
Expression profile of genes associated with the accumulation of triacylglycerol (TAG) in Auxenochlorella protothecoides KP7 under alkaline pH and nitrogen starvation conditions
Andeden, Enver Ersoy; Ozturk, Sahlan; Aslim, Belma
Identification of target genes related to lipid accumulation in microalgae can increase triacylglycerol production without affecting biomass production through genetic manipulation. This study is part of our previous study and aimed to determine the effects of nitrogen starvation, alkaline pH (pH 10), and a combination of these factors on the transcriptional profiles of eight genes potentially related to triacylglycerol accumulation in Auxenochlorella protothecoides KP7. As shown previously, triacylglycerol content in Auxenochlorella protothecoides KP7 reached the maximum level under combined stress conditions. In this study, the highest upregulation for the gene encoding phosphoenolpyruvate carboxylase (PEPC) was observed under both nitrogen starvation and combined stress. Nitrogen starvation alone resulted in a significant increase in the expression level of all genes except NADP-malic enzyme (MEchl), which is localized in the chloroplast. Compared with nitrogen starvation alone, the upregulation of pyruvate dehydrogenase complex E2 component (PDHC-E2), glycerol-3-phosphate dehydrogenase (GPDH), diacylglycerol acyltransferase 1 (DGAT1), and MEchl genes further increased under the combined stress. These results suggest that genes encoding the enzymes DGAT1, GPDH, ME, PEPC, and PDHC-E2 are associated with triacylglycerol accumulation and could be used as target genes for genetic modification of Auxenochlorella protothecoides and possibly other microalgal species.
2023-01-25T00:00:00ZAuthentication and quality assessment of meat products by fourier-transform infrared (FTIR) Spectroscopy
http://hdl.handle.net/20.500.11787/7975
Authentication and quality assessment of meat products by fourier-transform infrared (FTIR) Spectroscopy
Candoğan, Kezban; Güneş Altuntaş, Evrim; İğci, Naşit
These days, food safety is getting more attention than in the recent past due to consumer awareness, regulations, and industrial competition to offer best quality products. Meat and meat products are very valuable but highly perishable. There is a need for reliable assessment techniques to ensure the safety and quality of these products throughout their shelf life. Classical analytical methods have been replaced with alternative, rapid, simple, and noninvasive methods to enhance productivity and profitability in the meat supply chain. Fourier-transform infrared (FTIR) spectroscopy has become a valuable analytical technique for structural or functional studies related to foods as a rapid, nondestructive, cost-efficient, and sensitive physicochemical fingerprinting method. This technique is readily applicable for routine quality control or industrial applications with a high degree of confidence. FTIR spectroscopy coupled with chemometrics has drawn attention to quality control, safety assessment, and authentication purposes in the meat and meat products domain. This review covers fundamental knowledge on FTIR spectroscopy coupled with chemometric techniques, as well as major applications of this robust method in meat science and technology for adulteration detection, monitoring biochemical and microbiological spoilage and shelf life, determining changes in chemical components such as proteins and lipids.
2021-03-30T00:00:00ZModern venomics--Current insights, novel methods, and future perspectives in biological and applied animal venom research
http://hdl.handle.net/20.500.11787/7974
Modern venomics--Current insights, novel methods, and future perspectives in biological and applied animal venom research
von Reumont, Bjoern M.; İğci, Naşit; Anderluh, Gregor; Antunes, Agostinho; Ayvazyan, Naira; Beis, Dimitris; Caliskan, Figen; Crnkovic, Ana; Damm, Maik; Dutertre, Sebastien; Ellgaard, Lars; Gajski, Goran; German, Hannah; Halassy, Beata; Hempel, Benjamin-Florian; Hucho, Tim; Ikonomopoulou, Maria P.; Karpat, Izhar; Klapa, Maria I.; Koludarov, Ivan; Kool, Jeroen; Lüddecke, Tim; Mansour, Riadh Ben; Modica, Maria Vittoria; Moran, Yehu; Nalbantsoy, Ayse; Pachon Ibanez, Maria Eugenia; Panagiotopoulos, Alexios; Reuveny, Eitan; Cespedes, Javier Sanchez; Sombke, Andy; Surm, Joachim M.; Undheim, Eivind AB; Verdes, Aida; Zancolli, Giulia
Venoms have evolved >100 times in all major animal groups, and their components, known as toxins, have been fine-tuned over millions of years into highly effective biochemical weapons. There are many outstanding questions on the evolution of toxin arsenals, such as how venom genes originate, how venom contributes to the fitness of venomous species, and which modifications at the genomic, transcriptomic, and protein level drive their evolution. These questions have received particularly little attention outside of snakes, cone snails, spiders, and scorpions. Venom compounds have further become a source of inspiration for translational research using their diverse bioactivities for various applications. We highlight here recent advances and new strategies in modern venomics and discuss how recent technological innovations and multi-omic methods dramatically improve research on venomous animals. The study of genomes and their modifications through CRISPR and knockdown technologies will increase our understanding of how toxins evolve and which functions they have in the different ontogenetic stages during the development of venomous animals. Mass spectrometry imaging combined with spatial transcriptomics, in situ hybridization techniques, and modern computer tomography gives us further insights into the spatial distribution of toxins in the venom system and the function of the venom apparatus. All these evolutionary and biological insights contribute to more efficiently identify venom compounds, which can then be synthesized or produced in adapted expression systems to test their bioactivity. Finally, we critically discuss recent agrochemical, pharmaceutical, therapeutic, and diagnostic (so-called translational) aspects of venoms from which humans benefit.
2022-05-18T00:00:00ZDetermination of the fibrinogenolytic activity of Montivipera raddei (Raddeʼs mountain viper) venom
http://hdl.handle.net/20.500.11787/7973
Determination of the fibrinogenolytic activity of Montivipera raddei (Raddeʼs mountain viper) venom
İğci, Naşit; Atasoy, Fikriye Seda
Snake venom fibrinogenolytic enzymes have diagnostic and therapeutic value and are important for snakebite pathology. In the present study, the fibrinogenolytic activity of Montivipera raddei venom was investigated. Crude venom was incubated with human fibrinogen for different times at 37°C. An inhibition study was carried out using different protease inhibitors. The fibrinogenolytic activity was assessed by SDS-PAGE and fibrinogen zymography. An HPLC-based method was used to obtain confirmatory data. Montivipera raddei venom predominantly cleaved the Aα chain of fibrinogen in a time-dependent manner. A very slight decrease in band intensity of the Bβ chain was observable after a longer incubation time. Cleavage of fibrinogen was confirmed by HPLC. Zymography revealed that the venom contained 50 and 75 kDa fibrinogenolytic enzymes. Ethylenediaminetetraacetic acid (EDTA) and 1,10-phenanthroline inhibited the overall fibrinogenolytic activity, while phenylmethylsulfonyl fluoride (PMSF) and aprotinin only inhibited the degradation of the Bβ chain. These results indicated that metalloproteinases were major fibrinogenolytic enzymes in the venom. An inhibitor study suggested the presence of serine proteinases that broke down the Bβ chain. With this study, the fibrinogenolytic activity of M. raddei venom was shown for the first time. The results will be useful for further isolation and characterization studies.
2022-12-21T00:00:00Z