The identification of antimicrobial metabolites biosynthesized by different organisms, but hidden in complex mixtures, are a major challenge in natural product (NP) drug discovery (Sahayasheela, 2022). We hypothesize that AI implemented in NP drug discovery, such as UPLC-HRMS/MS-based dereplication combined with in silico target prediction and biochemometric approaches have the potential to accelerate the discovery of novel and urgently needed antimicrobial agents. In a recent study we could demonstrate the potency of a ¹H NMR/MS-based biochemometric workflow (Langeder, 2023) to detect chemical features out of complex mixtures even prior to isolation. This approach will be extended towards a correlation of 2D NMR spectra (HSQC, HMBC) with bioactivity data derived from the phenotypic screening against P. aeruginosa and Candida sp. Different metabolite patterns from supernatants/extracts triggered by different stimuli (e.g., by co-cultures derived from the antagonism of Pseudomonas and Candida) will be correlated with bioactivity data. We expect the 2D-biochemometric approach to be particularly useful to cope with (i) the abundance of biosynthetic analogs and (ii) the overlapping resonances in the ¹H NMR spectra. This way, anti-microbial and synergistically acting constituents will be identified and isolated for an in silico anti-infective target- and ADMET profiling followed by experimental assessment and if appropriate exploited by synthesis.

Within the target-based drug discovery approach, we will contribute to isolate non-commercially available NPs virtually predicted as ligands of the envisaged targets. For this purpose, most suitable natural sources for the extraction and isolation of virtual hits will be selected. Chemically characterized isolates will be forwarded to the faculty members for mechanism of action investigations and exploratory formulation studies.

UPLC-HRMS/MS (Sciex X500R QTOF-MS) is used for dereplication of multicomponent mixtures and for monitoring the targeted isolation of virtual hits and their congeners using high-performance counter current chromatography (HPCCC) and supercritical fluid chromatography (SFC-DAD/ELSD/QDa); structure identification and hetero-covariance analyses are performed by 1D and 2D NMR experiments (Prodigy CryoProbe 500 NMR).