s. pneumoniae

Ethylhydrocupreine hydrochloride (Optochin hydrochloride) is a derivative of quinine with antimicrobial activity against Streptococcus pneumoniae and antimalarial activity with an IC50 of 25.75 nM against Plasmodium falciparum. It is also an agonist of Gallus gallus2 receptors (ggTas2r1, ggTas2r2, and ggTas2r7).

Solithromycin (OP-1068) is an orally bioavailable antimicrobial agent that inhibits cell viability, protein synthesis, and growth rate of Streptococcus pneumoniae, Staphylococcus aureus, Staphylococcus aureus, and Haemophilus influenzae with IC50 values of 7.5 ng/mL, 40 ng/mL, and 125 ng/mL, respectively.Solithromycin inhibits protein biosynthesis by binding to the large 50S subunit of the ribosome.

Cefuroxime (Cephuroxime) is an orally active second-generation cephalosporin antibiotic with antimicrobial activity that inhibits both Gram-positive and Gram-negative bacteria, and is used in the study of soft tissue infections.

α2-3 Neuraminidase S, Streptococcus pneumoniae, is a glycoside hydrolase enzyme capable of hydrolyzing the glycosidic bonds of neuraminic acid.

O-Glycanase, Streptococcus pneumoniae, acts on core disaccharides containing N-acetylgalactosamine.

Topoisomerase IV, Streptococcus pneumoniae (EC 5.99.1.), is produced by overexpressing its subunit in Escherichia coli.

Blasticidin S HCl is a natural product and an inhibitor of protein synthesis. Blasticidin S HCl is a broad-spectrum antibiotic that can inhibit the cell growth of prokaryotes, fungi, plants and mammalian cells.

LB 11058 is a novel injectable cephalosporin featuring a C-3 pyridyl-substituted vinyl sulfide and a C-7 2-amino-5-chloro-1,3-thiazole group. This compound exhibits exceptional activity against Streptococcus pneumoniae and demonstrates similar efficacy against β-hemolytic streptococci. The inhibition pattern for LB 11058 with S. aureus is consistent, as all isolates are inhibited under this pattern.

PD-L1/LpxC-IN-1 (Compound 12b) is an inhibitor of PD-L1 and LpxC, with IC50 values of 5.2 μM and 0.081 μM, respectively. This compound disrupts bacterial lipopolysaccharide biosynthesis, leading to bacterial cell lysis and death. It effectively inhibits Gram-negative bacteria, exhibiting a minimum inhibitory concentration (MIC) of 0.25-0.5 μg/mL against K. pneumoniae ATCC 13883, E. coli ATCC 8739, S. typhimurium ATCC 14028, and P. aeruginosa ATCC 9027. Additionally, PD-L1/LpxC-IN-1 modulates the immune response by downregulating the expression of inflammatory cytokines IL-2 and IFN-γ, and upregulating CD4+ and CD8+ cells, thus activating the immune system and mitigating excessive inflammatory responses. In a mouse model of K. pneumoniae ATCC 13883 infection, PD-L1/LpxC-IN-1 demonstrated antibacterial activity.

Lipopolysaccharides from Klebsiella pneumoniae (LPS, from bacterial [Klebsiella pneumoniae]) are lipid-polysaccharide endotoxins and TLR4 activators originating from Klebsiella pneumoniae, classified as S-type LPS. They exhibit a characteristic tripartite structure comprising an O-antigen, a core oligosaccharide, and lipid A. These lipopolysaccharides may contribute to bacterial immune evasion by inhibiting complement-mediated killing and suppressing host antimicrobial peptide secretion, thus helping bacteria evade immune defenses. Possessing high viscosity and serum resistance, they can potentially induce sepsis. Additionally, these lipopolysaccharides are utilized in the development of animal models for sepsis/septicemia.

Topoisomerase inhibitor6 (Compound REDX05931) is a dual irreversible inhibitor of DNA gyrase and topoisomerase IV, with an MIC of 0.06 μg/mL against fluoroquinolone-resistant S. aureus. It halts the DNA strand breaking-rejoining process, causing lethal DNA damage, and holds potential for studying infections caused by Gram-positive bacteria such as S. aureus and S. pneumoniae.

MBL-IN-6 (Compound 6d) is a metal-β-lactamase (MBL) inhibitor with Ki values of 2.6 μM for NDM-1 and 0.08 μM for VIM-2. It acts synergistically with Imipenem against clinical isolates producing MBL, such as E. coli SI-M001, K. pneumoniae T2301, and S. marcescens SI-1591, with a MIC ranging from 2-64 μg/mL. MBL-IN-6 does not induce off-target effects and exhibits no inhibitory activity against ACE-1. This compound is useful for research on antibiotic resistance.

RNAP-σ interaction-IN-4 (Compound 3a) is an inhibitor of the interaction between RNA polymerase and the sigma factor (RNAP-σ). It has a minimum inhibitory concentration (MIC) of 1 μg/mL against S. pneumoniae and 2 μg/mL against S. aureus. This compound exhibits potent bactericidal properties by disrupting bacterial transcription through interference with the β′CH−σ interaction. Additionally, RNAP-IN-2 has demonstrated significant efficacy in a sepsis model. RNAP-σ interaction-IN-4 is applicable for studying Gram-positive bacterial infections involving multidrug-resistant strains.

ZLWH-67 is a β‑Carboline derivative and an antibacterial agent. It inhibits DNA synthesis, disrupts biofilm formation, and increases reactive oxygen species (ROS) levels. ZLWH-67 exhibits strong in vitro antibacterial activity against MRSA (MIC= 0.5-4 μg/mL), S. epidermidis (MIC= 4 μg/mL), E. faecalis (MIC= 4-8 μg/mL), and S. pneumoniae (MIC= 16 μg/mL). Additionally, it demonstrates anti-MRSA effects in murine skin and pneumonia infection models.

Leucomycin a5 is a metabolite from the leucomycin complex, which was originally isolated from S. kitasatoensis. It is active against a variety of Gram-positive and Gram-negative bacteria (MICs = 0.04-0.8 µg/ml) but not against K. pneumoniae, S. typhimuriu

(+)-δ-Cadinene is a sesquiterpene from G. hirsutum with antibacterial, insecticidal, anticancer and antiproliferative activities. It showed a MIC value of 31.25 μg/ml against S. pneumoniae and LC50s values of 8.23, 9. 2 and 3 against third instar larvae of A. stephensi, A. aegypti and C. quinquefasciatust, respectively.(+)-δ-Cadinene (10, 50 and 100 μM) induced apoptosis and inhibited the growth of OVCAR-3 human ovarian cancer cells apoptosis and inhibited their proliferation.

(-)-Viriditoxin is a mycotoxin originally isolated from A. viridinutans that has antibacterial and antiproliferative activity. It is active against methicillin-sensitive and -resistant S. aureus (MSSA and MRSA, respectively), tetracycline-sensitive and -resistant Staphylococcus, vancomycin-sensitive and -resistant Enterococcus, and penicillin-sensitive and -resistant S. pneumoniae (MICs = 2-32 μg/ml). (-)-Viriditoxin is also active against fish pathogens, including S. iniae and S. parauberis (MICs = 0.16-0.21 μg/ml). It inhibits polymerization and the GTPase activity of E. coli FtsZ, a tubulin-like GTPase involved in bacterial cell division (IC50s = 8.2 and 7 μg/ml, respectively). (-)-Viriditoxin inhibits proliferation of human DU145, LNCaP, and PC3 prostate cancer cells (IC50s = 5.36, 0.63, and 7.6 μM, respectively) . It is also toxic to mice (LD50 = 2.8 mg/kg, i.p.).

10'-Desmethoxystreptonigrin is an antibiotic originally isolated from Streptomyces and a derivative of the antibiotic streptonigrin. It is active against a variety of bacteria, including S. aureus, S. faecalis, E. coli, K. pneumoniae, and P. vulgaris (MICs = 0.4, 1.6, 3.1, 3.1 and 0.4 μg/ml, respectively). 10'-Desmethoxystreptonigrin is cytotoxic to HCT116 colon and A2780 ovarian cancer cells (IC50s = 0.004 and 0.001 μg/ml, respectively), as well as HCT116 cells resistant to etoposide and teniposide and cisplatin-resistant A2780 cells (IC50s = 0.003, 0.001, and 0.01 μg/ml, respectively). 10'-Desmethoxystreptonigrin is also an inhibitor of p21ras farnesylation (IC50 = 21 nM).

Deethylindanomycin is a polyether antibiotic that has been found in S. setonii. It is active against a variety of Gram-positive bacteria, including various strains of S. aureus and Streptococcus, as well as one strain of S. pneumoniae (MICs = 4, 4, and 2 μg/ml, respectively). It is also active against coccidia in vitro, inhibiting E. tenella development, but is inactive against E. tenella infection in chicks when administered at a dose of 200 μg/g in the diet. Deethylindanomycin acts as an ionophore in lipid bilayer membranes and is more selective for potassium ions than calcium, magnesium, and sodium ions. It induces histamine release from rodent mast cells and human basophils in vitro in a calcium-dependent manner.

Actinopyrone A is a pyrone isolated from S. pactum with diverse biological activities, showing selective and potent antimicrobial activity against H. pylori (MIC = 0.1 ng/mL) and no activity against other Gram-negative bacteria including E. coli, K. pneumoniae, P. aeruginosa, and B. fragilis. It mildly inhibits the growth of Gram-positive bacteria and dermatophytes with MIC values ranging from <6.25 to 25 μg/mL. Intravenous administration of actinopyrone A (30 μg/kg) increases coronary blood flow in dogs by 196.2%.

Flumequine-13C3 is intended for use as an internal standard for the quantification of flumequine by GC- or LC-MS. Flumequine (T1060) is a fluoroquinolone antibiotic.1It is active againstS. aureus, S. pyogenes, B. subtilis, E. coli, P. aeruginosa, S. faecalis, andK. pneumoniae (MICs = 1-100 μg/ml). Flumequine (T1060) is also active against field isolates of B. hyodysenteriae (MICs = 6.25-200 μg/ml).2It inhibits DNA gyrase, disrupting supercoiling of bacterial DNA to block transcription and replication.3

Desacetylcefotaxime is an active metabolite of the cephalosporin antibiotic cefotaxime .1It is active against 60 clinical isolates derived from patients with meningitis, includingH. influenzae,S. pneumoniae,S. agalactiae, andN. meningitidis(MIC90s = 0.008-0.12 μg/ml). 1.Jones, R.N.Cefotaxime and desacetylcefotaxime antimicrobial interactions. The clinical relevance of enhanced activity: A reviewDiagn. Microbiol. Infect. Dis.22(1-2)19-33(1995)

Desotamide, a cyclic hexapeptide antibiotic originally isolated from Streptomyces, is active against S. aureus, S. pneumoniae, and methicillin-resistant S. epidermidis (MRSE; MICs = 16, 12.5, and 32 μg/ml, respectively).

Quinaldopeptin is a quinomycin antibiotic. It is active against a variety of bacteria, including S. pyogenes, S. aureus, C. perfringens, S. faecalis, E. coli, and K. pneumoniae (MICs = 0.2, 0.4, 0.8, 1.6, 3.1 and 6.3 μg/ml, respectively). It is cytotoxic to B16/F10 and Moser cells (IC50s = 0.0008 and 0.04 μg/ml, respectively) and increases survival in a P388 leukemia mouse model. Quinaldopeptin is a bis-intercalator depsipeptide (NPBID) that binds to and intercalates into DNA (Kd = 32 nM).