Opine-type metalóforos marcados como novas sondas dirigidas de imagem PET para deteção seletiva de infeção por Superbacterias

The main goal of SuperOpTyMe is to investigate and optimize the possible use of 64Cu, 67Ga and, at a later stage, 89Zr labeled OpTyMe complexes as new probes for the efficient and selective infection imaging, to be applied in the prompt diagnosis of infections by the above-cited MDR bacteria S. aureus, P. aeruginosa, Yersinia pestis and Paenibacillus mucilaginosus. Furthermore, there is growing evidence that the last step of OpTyMe biosynthesis in these bacteria, involving opine dehydrogenases (ODHs) enzymes, plays an important role in metal acquisition and is highly correlated with bacterial virulence, thus opening new opportunities for their infection treatment by new and efficient antibiotics [11]. To reach this ambitious goal, a multi/transdisciplinary approach will be followed, exploiting the complementary skills of an ad-hoc built research team able to tackle the above-mentioned challenges within the same project for the first time, profiting of team’s competencies in organic, analytical and radiopharmaceutical chemistry, as well as molecular biology and medicine. All this taking advantage of the instrumentation and all other facilities offered by the prestigious institutions hosting the team, i.e., Centro de Ciências e Tecnologias Nucleares (C2TN) of Instituto Superior Técnico (IST), University of Messina (UniME, Italy), University of A Coruña (UDC, Spain), Centro de Investigación Cooperativa en Biomateriales (CIC biomaGUNE, San Sebastián, Spain), and Instituto de Saúde Ambiental (ISAMB) of the Faculty of Medicine, Univ. of Lisbon. As such, SuperOpTyMe will gather together different competencies and skills to combine, under a single and articulate project, a set of results from different research fields. In particular, to give response and solution to the mentioned challenges, the work will be articulated as follows (in parenthesis the reference tasks, main institutions and initials of team members, as specified in the dedicated sections): Challenge 1: Synthesis and characterization of selected OpTyMe, following the procedures already described in literature(Spine, Ppaline) [12, 13], and development of the total synthesis of Ypine and Bpaline, based on previous protocols (T1; C2TN: SG, PC and UDC: CJ). Challenge 2: Detailed characterization of the acid-base properties of the OpTyMe of interest and their binding ability towards target metal ions (the labeling relevants, as Cu2+, Ga3+ and, on a later stage, Zr4+), as well as the main cations of biological fluids (e.g., Na+, K+, Mg2+, Ca2+), followed by the modelling of the chemical speciation of OpTyMe and their metal complexes in biological fluids (T2; C2TN: SG, PC and UniMe: DM). Challenge 3: Radiolabeling of OpTyMe with the radioisotopes of interest (starting with 64Cu and 67Ga and, at a later stage, 89Zr) together with the synthesis and characterization of the cold congeners of metal OpTyMe complexes (Cu2+, Ga3+ and Zr4+) (T3; C2TN: SG, PC, EP, LG). Evaluation of the selective recognition of OpTyMe and their metal complexes towards target bacterial strains (Spine by S. aureus, Ppaline by P. aeruginosa, Ypine by Yersinia pestis and Bpaline by Paenibacillus mucilaginosus), and comparison between results obtained with laboratorial bacterial strains and real samples (T4; C2TN: TM, LG and ISAMB: CL, DG). Imaging and ex-vivo biodistribution studies of the radiolabeled OpTyMe in infection Murine/mice models (T5; C2TN: LG and CIC biomaGUNE: JL).