Unit:
Specialty BiotechnologyLibrary of the School of Science
Supervisors info:
Δημήτρης Χατζηνικολάου, Αναπληρωτής Καθηγητής, Τμήμα Βιολογίας, ΕΚΠΑ
Διομή Μαμμά, Επίκουρη Καθηγήτρια, Σχολή Χημικών Μηχανικών, ΕΜΠ
Ευστάθιος Κατσίφας, ΕΔΙΠ, Τμήμα Βιολογίας, ΕΚΠΑ
Original Title:
«Διερεύνηση των ρυθμιστικών παραγόντων της βιοαποθείωσης στον πρότυπο βιοκαταλύτη Rhodococcus qingshengii IGTS8»
Translated title:
«Exploring the regulatory aspects of biodesulfurization in the model biocatalyst Rhodococcus qingshengii IGTS8»
Summary:
Bacteria belonging to the genus Rhodococcus, in particular Rhodococcus qingshengii IGTS8, have emerged as promising candidates for the desulfurization of crude oil, and especially for dibenzothiophene (DBT) desulfurization. As global regulations on sulfur emissions become more stringent, the need for lower sulfur content in petroleum and thus the need to scale up biodesulfurization processes, becomes crucial. Among the various methods for sulfur removal from petroleum, the 4S metabolic pathway stands out as the most promising. This pathway allows for sulfur removal while maintaining the caloric value of the fuel and is encoded in by the dszABC plasmid-borne operon in Rhodococcus strain IGTS8. The 4S enzymes catalyze the conversion of DBT to 2-hydroxybiphenyl (2-HBP), however, the efficiency of the pathway can be inhibited by various factors, with sulfur-containing amino acids such as cysteine and methionine, as well as sulfates, being among the most common repressors. Overcoming these repression mechanisms is essential to maximize the efficiency of the biodesulfurization process. In this study, we aim to explore the effects of different combinations of carbon and sulfur sources, using Medium C, an optimized culture medium that alleviates the repressive effect of sulfate. Furthermore, this study includes a comparative proteomic analysis aimed at providing deeper insights into the regulatory circuits governing the expression of the dszABC biodesulfurization genes. In conclusion, understanding how different carbon and sulfur sources affect the desulfurization process in vivo, along with a comparative proteomic analysis, represents a critical step towards the development of an optimized biodesulfurization process. This, in turn, can contribute to the design of novel strategies for greater biocatalyst efficiency and process up-scalability, with the goal of cleaner and more sustainable energy solutions.
Main subject category:
Science
Keywords:
Rhodococcus qingshengii IGTS8, Dibenzothiophene, Biodesulfurization, Carbon metabolism, Regulation
File:
File access is restricted until 2027-03-28.
Biodesulfurization Thesis.pdf
2 MB
File access is restricted until 2027-03-28.
