In this thesis were analyzed the mechanisms of hop inhibition, tolerance and adaptation in beer spoiling Lactobacillus (L.) brevis TMW 1.465, on various cellular levels, and the mode of antibacterial action of hop compounds in artificial planar lipid bilayer systems in order to establish a model on the interaction of the multiple resistance mechanisms. It was demonstrated that the antibacterial effect of hop compounds resides in their function as proton ionophores and also redox reactive uncouplers. Beyond previously described transmembrane transport-based hop resistance mechanisms, hop adaptation in L. brevis TMW 1.465 is a multifactorial process, which results in changes in metabolism, protein profile, membrane and cell wall composition and intracellular manganese levels. It involves mechanisms to cope with intracellular acidification and divalent cation limitation, redox imbalance and oxidative damage and mechanisms for energy generation and economy, genetic information fidelity and enzyme functionality, and as a result enables beer spoilage.