Author, Institution: Ingrida Sabaliauskė, Kaunas University of Technology
Science area, field of science: Technological Sciences, Chemical Engineering, T005
Research Supervisor: Prof. Dr. Naglis Malys (Kaunas University of Technology, Technological Sciences, Chemical Engineering, T005)
Dissertation Defence Board of Chemical Engineering Science Field:
Prof. Dr. Petras Rimantas Venskutonis (Kaunas University of Technology, Technological Sciences, Chemical Engineering, T005) – chairperson
Prof. Dr. Hab. Juozas Vidas Gražulevičius (Kaunas University of Technology, Technological Sciences, Chemical Engineering, T005)
Dr. Erik Kurt Reinhard Hanko (University of Manchester, United Kingdom, Natural Sciences, Biochemistry, N004)
Prof. Dr. Daiva Leskauskaitė (Kaunas University of Technology, Technological Sciences, Chemical Engineering, T005)
Prof. Dr. Edita Sužiedėlienė (Vilnius University, Natural Sciences, Biochemistry, N004)
Dissertation defence meeting will be at Rectorate Hall of Kaunas University of Technology (K. Donelaičio 73 – 402, Kaunas)
The doctoral dissertation is available at the library of Kaunas University of Technology (Gedimino 50, Kaunas) and on the internet: I. Sabaliauskė el. dissertation.pdf
© I. Sabaliauskė, 2026 “The text of the thesis may not be copied, distributed, published, made public, including by making it publicly available on computer networks (Internet), reproduced in any form or by any means, including, but not limited to, electronic, mechanical or other means. Pursuant to Article 25(1) of the Law on Copyright and Related Rights of the Republic of Lithuania, a person with a disability who has difficulties in reading a document of a thesis published on the Internet, and insofar as this is justified by a particular disability, shall request that the document be made available in an alternative form by e-mail to doktorantura@ktu.lt.”
Annotation: This dissertation presents the development and characterization of genetically encoded biosensors responsive to gallic acid and gentisic acid, and their application in the analysis of plant-derived, clinical, and biological samples. During the development of the gallic acid biosensor, 4-oxalomesaconic acid was identified as the actual inducer of the regulatory system. Activation of the biosensor required the presence of gallate dioxygenase and a specific transporter protein. The optimized system was subsequently applied for the quantification of gallic acid in green tea extracts. In the case of the gentisic acid biosensor, 3-maleylpyruvic acid was determined to be the actual inducing molecule, with biosensor activation dependent on gentisate dioxygenase and an associated transporter protein. This biosensor was successfully employed for the quantification of gentisic acid in synthetic urine samples. Furthermore, the chemolithoautotrophic bacterium Cupriavidus necator H16 was genetically engineered to enable the production and accumulation of gentisic acid. The modified strain demonstrated gentisic acid synthesis under both heterotrophic and autotrophic growth conditions, utilizing the C1 carbon source formic acid.