Final answer:
The incorrect statement about autoinducers is that they inhibit bacterial growth. Autoinducers are signaling molecules used in quorum sensing to regulate gene expression, not to impede growth.
Step-by-step explanation:
The statement about autoinducers that is incorrect is that they inhibit bacterial growth. Autoinducers are indeed signaling molecules involved in quorum sensing, a process where bacterial cell density influences the regulation of gene expression. When the concentration of autoinducers reaches a certain threshold, they bind to specific receptors, initiating a signaling cascade that can lead to a variety of responses, including the formation of biofilms and the regulation of virulence factors. These molecules typically do not inhibit growth but rather enable bacteria to coordinate their behavior. Notably, autoinducers like N-acylated homoserine lactones (AHL) for Gram-negative bacteria or small peptides for Gram-positive bacteria, bind to transcription factors or kinases to regulate the expression of genes, including those responsible for the production of more autoinducers, often resulting in a positive feedback loop.