Fig. 4: Lactylation affects receptor-independent alpha-toxin membrane association.
From: Post-translational toxin modification by lactate controls Staphylococcus aureus virulence
a Model of the alpha-toxin pore according to the structure reported by Song et al.34, rendered using Lasergene 17 Protean 3D. The position of K84 is highlighted using space fill presentation of the lysine side chain within one monomer shown in red. Note we counted amino acids from the start of the Hla precursor peptide (not the mature toxin) in this study. b Model of alpha-toxin (Hla) lactylation and steps leading to pore formation: (1) Attachment of Hla monomer to membrane involving ADAM-10 receptor, (2) oligomerization on the membrane, which includes structural changes leading to SDS stability, (3) pore formation involving considerable structural changes including stem formation and anchoring to caveolin-1. c Binding ability of alpha-toxin to ADAM−10 and caveolin-1 (n = 3 independent experiments). Purified His-tagged wild-type or K84R alpha-toxin were incubated with A549 cell lysate for the indicated times. The binding proteins were collected via His-tag pull-down and detected by immunoblot. “Input”: A549 cell lysate only; “Mock”: A549 cell lysate incubated with equal amount of PBS for 24 h.
