This project aimed to characterize inter-species interactions between the A. fumigatus and K. pneumoniae microbial pathogens by analyzing the proteomic profiles of single-pathogen cultures and co-cultures. Biofilms of both A. fumigatus and K. pneumoniae were grown for 24 hours at 37°C in 3 mL of YNBP minimal medium [1.7 g/L yeast nitrogen base (YNB) without amino acids, 5g/L ammonium sulfate, 25 mM phosphate buffer pH 7.0 (KH2PO4 + K2HPO4), 2.5 mM N-acetyl-glucosamine, 0.2% glucose, 0.1% maltose]. Protein pellets obtained from these conditions were further analyzed, revealing metabolic rearrangements and differences in cell cycle regulation due to the interaction. Proteomic profiling, in general, provided new insights into the metabolic reshaping critical for the pathogens to navigate in the course of polymicrobial infection. Additionally, an exploration of the produced compounds uncovered potential biomarker candidates.