Neuronal damage is a major consequence of bacterial meningitis, but little is known about mechanisms of bacterial interaction with neurons leading to neuronal cell death. Streptococcus pneumoniae (pneumococcus) is a leading cause of bacterial meningitis and many survivors develop neurological sequelae after the acute infection has resolved, possibly due to neuronal damage. Here, we studied mechanisms for pneumococcal interactions with neurons. Using human primary neurons, pull-down experiments and mass spectrometry, we show that pneumococci interact with the cytoskeleton protein β-actin through the pilus-1 adhesin RrgA and the cytotoxin pneumolysin (Ply), thereby promoting adhesion and invasion of neurons, and neuronal death. Using our bacteremia-derived meningitis mouse model, we observe that RrgA- and Ply-expressing pneumococci co-localize with neuronal β-actin. Using purified proteins, we show that Ply, through its cholesterol-binding domain 4, interacts with the neuronal plasma membrane, thereby increasing the exposure on the outer surface of β-actin filaments, leading to more β-actin binding sites available for RrgA binding, and thus enhanced pneumococcal interactions with neurons. Pneumococcal infection promotes neuronal death possibly due to increased intracellular Ca2+ levels depending on presence of Ply, as well as on actin cytoskeleton disassembly. STED super-resolution microscopy showed disruption of β-actin filaments in neurons infected with pneumococci expressing RrgA and Ply. Finally, neuronal death caused by pneumococcal infection could be inhibited using antibodies against β-actin. The generated data potentially helps explaining mechanisms for why pneumococci frequently cause neurological sequelae. Author summary: Neuronal damage is a major consequence of meningitis. Streptococcus pneumoniae (pneumococcus) is the leading etiological cause of bacterial meningitis, yet how pneumococci interact with neurons and cause neuronal death is poorly understood. Using human neurons in vitro and our established bacteremia-derived meningitis mouse model in vivo, we found that pneumococci use the pilus-1 adhesin RrgA and the cytotoxin pneumolysin (Ply) to interact with neuronal β-actin expressed on the plasma membrane. Also, we demonstrate that Ply interaction with the neuronal plasma membrane increase the exposure of β-actin on the neuronal plasma membrane, allowing more pneumococci to adhere to neurons through RrgA-β-actin interaction. Moreover, neurons infected with RrgA- and Ply-expressing pneumococci showed increased intracellular Ca2+ levels and disruption of β-actin filaments, possibly leading to neuronal death. Importantly, by blocking pneumococcal-β-actin interaction using antibodies, we could reduce neuronal cell death after pneumococcal infection. [ABSTRACT FROM AUTHOR]