α-hemolysin

α-Hemolysin (Staphylococcus aureus), a polypeptide virulence factor of Staphylococcus aureus, disrupts host cell plasma membranes. Upon binding to the cell surface, its monomers create a homoheptamic prepore, which evolves into a mature transmembrane pore, facilitating K+ and Ca2+ ion transport that induces necrotic death in target cells [1].

Delta-hemolysin (Delta-lysin) TFA is a peptide composed of 26 amino acids, produced by staphylococci as a hemolytic peptide. It may slightly disrupt cell membranes or lead to cell lysis and serves as a model for studying peptide-membrane interactions. Its activity against bacteria is relatively weak.

Cyrtominetin is an α-hemolysin inhibitor that works by directly binding to α-hemolysin and altering the conformation of its critical "Loop" region, subsequently inhibiting its lytic activity through a novel mechanism. This characteristic positions Cyrtominetin as a potential therapeutic agent against α-HL-mediated pathogenesis.

H052 is a selective inhibitor of Staphylococcus aureus α-hemolysin (Hla). It binds to the Hla monomer, disrupting its interaction with the host cell membrane, thereby blocking pore formation and inhibiting calcium influx, cytotoxicity, and inflammatory response. H052 exhibits inhibitory activity against Hla-induced calcium influx (EC50 = 30 nM in U937 cells) and holds potential for research into lung infections caused by S. aureus.

Oroxylin A 7-O-β-d-glucuronide and wogonoside should also be served as the chemical markers together with baicalin for the quality control of herbs and proprietary traditional Chinese medicine (PTCM) products of radix Scutellariae. Oroxylin A 7-O-glucuronide, Oroxin A, and Oroxin B can bind to the "stem" region of α-hemolysin (α-HL), when inhibiting the hemolytic activity of α-HL. Oroxylin A 7-O-glucuronide and 4', 5, 7-trihydroxy-6-methoxyflavone at a concentration of 100 microM inhibit 34 and 43% of total prolyl oligopeptidase (POP) activity, respectively.

Tosatoxumab (AR-301; KBSA301) is a fully human immunoglobulin-class monoclonal antibody that targets and neutralises Staphylococcus aureus (S. aureus) α-toxin (α-haemolysin; Hla), thereby serving as an antibiotic-adjuvant therapy for S. aureus ventilator-associated pneumonia (VAP).

Clindamycin-d3 (hydrochloride) is the deuterated form of Clindamycin. Clindamycin is an orally active, broad-spectrum lincosamide antibiotic that efficiently inhibits bacterial protein synthesis. It can suppress the expression of virulence factors in Staphylococcus aureus at sub-inhibitory concentrations (sub-MICs). Resistance to Clindamycin arises from the enzymatic methylation of the antibiotic binding site on the 50S ribosomal subunit (23S rRNA). It also reduces the production of leukocidin (PVL), toxic shock syndrome toxin-1 (TSST-1), and α-hemolysin (Hla). Additionally, Clindamycin is utilized in malaria research.

Oroxylin A 7-O-β-d-glucuronide (Standard) is a reference standard for research and analysis in studies involving Oroxylin A 7-O-β-d-glucuronide. Oroxylin A 7-O-β-d-glucuronide and wogonoside should also be served as the chemical markers together with baicalin for the quality control of herbs and proprietary traditional Chinese medicine (PTCM) products of radix Scutellariae. Oroxylin A 7-O-glucuronide, Oroxin A, and Oroxin B can bind to the "stem" region of α-hemolysin (α-HL), when inhibiting the hemolytic activity of α-HL. Oroxylin A 7-O-glucuronide and 4', 5, 7-trihydroxy-6-methoxyflavone at a concentration of 100 microM inhibit 34 and 43% of total prolyl oligopeptidase (POP) activity, respectively.

2,3-Dehydrokievitone, an isoflavone extracted from Erythrina sacleuxii, has antimicrobial activity against methicillin-resistant Staphylococcus aureus infections by decreasing the expression of α-hemolysin.