Fig. 1

Biofilm formation and quorum sensing. This figure shows four steps in a biofilm life cycle and the associated factors participating biofilm development and quorum sensing. Biofilm starts from bacteria initial attachment, and then develops into irreversible attachment. During these two periods, extracellular DNA, proteases, cell surface proteins or biofilm-associated proteins are involved in biofilm initiation. In the following steps, ECM is generated, and biofilm becomes mature. A cell–cell communication mechanism, called quorum sensing (QS), plays an important role in last two steps of biofilm formation. Multiple autoinducers and corresponding transcriptional receptors are regulating varieties of virulence factors production, contributing to the biofilm control and environmental equilibrium. Last but not least, the bacteria could disperse from the biofilm to find new niches and initiate new biofilm formation, thus resulting in the completion of biofilm life cycle. The strategies on anti-biofilm formation mainly target on each step of biofilm development, including the inhibition of adhesive matrix and microbial attachment, disturbing ECM generation and interruption of QS signaling