The scientific efforts of INTEGRATE were carried out in three work-packages involving concerted action of several beneficiaries. ‘Computer-aided molecular design’ work package developed, and distributed among partners molecular models for LsrK, glyoxylate shunt, GyrB, OASS-B, SurA and ClpP. The molecular models served as the guide for the rational design of new chemotypes and for the interpretation of the molecular basis of the ligand’s activity. Virtual screening campaigns to identify and optimizenew LsrK, glyoxylate shunt and gyrase B inhibitors were taken.
‘Medicinal and synthetic organic chemistry’ work-package exploited medicinal and synthetic organic chemistry activities and synthesize low molecular-weight compounds to target gyrase B, OASS and ClpP. The design of the compounds was based on the modeling results of work package 1. The activity within this work package included heavy medicinal chemistry optimization campaign for improving the identified target inhibitor activities to development of novel synthetic approaches for the synthesis of novel chemotypes. The synthesized compounds were tested for target inhibition in a biochemical assay. Proof-of-concept was obtained that inhibitory compounds acting at (low) micromolar concentration could be developed for each of these targets.
The activities within the ‘Molecular microbiology and bioactivity screening’ work package characterized and validated the targets for antimicrobial intervention and characterized the impact of the novel low-molecular weight compounds on a previously validated target. To this end, target-based, automation-compatible and scalable assays for high-throughput screening (HTS) of chemical libraries were set-up, validated, and used to perform several screening campaigns for OASS, LsrK, malate synthase and ClpP. Potent low molecular weight compounds inhibitors were discovered for several targets and the antimicrobial activity of the most promising compounds was validated. Notably, advanced structural and functional characterization of the purified target proteins was performed to understand the targets biochemical features and potential as antibacterial drug targets. This included solved X-ray crystals structures for malate synthase. Additionally, the activities provided enabling technologies that facilitate HTS, mechanism of action, resistance mechanism(s) and in vivo validation of low-molecular weight compound hits.
The scientific highlights of the consortium wide activities resulted in numerous conference presentations and, so far, 16 scientific publications, with several manuscripts being currently in a drawing up phase.
