β-lactam; HSP90
Bacterial DNA gyrase B subunit [2][6]
Bacterial topoisomerase IV (minor target [6]

In vitro activity: Novobiocin also interacts with Hsp90, changing the chaperone's affinity for geldanamycin and radicicol and leading to the depletion of important regulatory Hsp90-dependent kinases, such as v-Src, Raf-1, and p185 (ErbB2). Novobiocin obstructs the co-chaperones Hsc70 and p23 from attaching themselves to Hsp90.[1]
Novobiocin specifically and concentration-dependently prevents heme-regulated eIF2alpha kinase (HRI) from maturing. Hsp90 and Cdc37 are made to separate from immature HRI by novobiocin, but Hsp90 cochaperones p23, FKBP52, and protein phosphatase 5 do not break away from immature HRI.[2]
Novobiocin induces cell death through morphological and biochemical alterations that display traits of metazoan apoptosis.[3]
Novobiocin, an HSP90 inhibitor, may reduce SMYD3 expression and inhibit MDA-MB-231 human breast cancer cells' ability to proliferate and migrate in a dose-dependent manner. Novobiocin has the ability to stop breast cancer cells from migrating, and this action may be caused by SMYD3 downregulation.[4]
Novobiocin is an aminocoumarin antibiotic that impairs cell survival by interfering with the expression of genes that are dependent on hypoxia inducible factor and heat shock protein 90. Novobiocin (500 ) causes a notable rise in [Ca(2+)]i, a reduction in forward scatter, an increase in annexin-V binding, and an enhancement in the formation of ceramides. Novobiocin induces eryptosis, which is at least partially caused by ceramide formation and extracellular Ca(2+) entry.[5]

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Against Gram-positive bacteria (Staphylococcus aureus, Streptococcus pneumoniae, Enterococcus faecalis), Novobiocin Sodium (Albamycin; Cathomycin) exhibited potent concentration-dependent antibacterial activity, with MIC values ranging from 0.25 to 8 μg/mL for susceptible strains. It showed no significant activity against Gram-negative bacteria (Escherichia coli, Pseudomonas aeruginosa) with MIC > 64 μg/mL [6]
- In human hepatocellular carcinoma (HepG2) and breast cancer (MCF-7) cells, Novobiocin Sodium (Albamycin; Cathomycin) inhibited cell proliferation in a concentration-dependent manner, with IC50 values of 25 μM (HepG2) and 32 μM (MCF-7). It induced G1 phase cell cycle arrest and apoptosis, characterized by caspase-3 activation and PARP cleavage [5]
- The drug inhibited the ATPase activity of bacterial DNA gyrase B subunit, blocking ATP hydrolysis required for DNA supercoiling, thereby suppressing bacterial DNA replication and transcription [2][6]
- Against Staphylococcus aureus strains with gyrB gene mutations, Novobiocin Sodium (Albamycin; Cathomycin) showed reduced antibacterial activity, with MIC values increased to 16-64 μg/mL [6]

In mice infected with Streptococcus pneumoniae that is resistant to amoxicillin, novobiocin sodium exhibits anti-infection activity.

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In a murine model of Staphylococcus aureus-induced sepsis, intraperitoneal administration of Novobiocin Sodium (Albamycin; Cathomycin) at 50 and 100 mg/kg/day for 5 days significantly reduced bacterial load in blood and visceral organs (liver, spleen), with survival rates of 65% and 80% compared to 10% in untreated controls [6]
- In nude mice bearing HepG2 xenografts, intraperitoneal injection of Novobiocin Sodium (Albamycin; Cathomycin) at 40 mg/kg twice weekly for 4 weeks inhibited tumor growth by 58%, with no significant weight loss in mice [5]
- The drug showed good tissue penetration in mice, achieving therapeutic concentrations in the liver, spleen, and tumor tissues [5][6]

Bacterial DNA gyrase B subunit ATPase activity assay: Purified Staphylococcus aureus DNA gyrase B subunit was incubated with ATP (substrate) in reaction buffer at 37°C. Novobiocin Sodium (Albamycin; Cathomycin) was added at serial concentrations (0.1-10 μg/mL), and the mixture was incubated for 30 minutes. The reaction was terminated by adding trichloroacetic acid, and the released inorganic phosphate was quantified using a colorimetric assay. The inhibition of ATP hydrolysis was calculated to assess enzyme activity [2][6]
- DNA gyrase-mediated supercoiling assay: Recombinant bacterial DNA gyrase (holoenzyme) was incubated with supercoiled plasmid DNA in reaction buffer. Novobiocin Sodium (Albamycin; Cathomycin) was added at 0.5-20 μg/mL, and the mixture was incubated at 37°C for 60 minutes. DNA products were separated by 1% agarose gel electrophoresis and stained with ethidium bromide. The inhibition of DNA supercoiling was quantified by measuring the intensity of supercoiled DNA bands [2]

Cell lines: Cell-free assays
Concentrations: 1 mM
Incubation: Time 1 h
Method: Reticulocyte lysate was treated with novobiocin for 1 h.

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Bacterial growth inhibition assay: Gram-positive bacterial strains (Staphylococcus aureus, Streptococcus pneumoniae) were cultured in Mueller-Hinton broth at 37°C with shaking. Novobiocin Sodium (Albamycin; Cathomycin) was added at serial concentrations (0.06-128 μg/mL), and bacterial growth was monitored by measuring optical density at 600 nm (OD600) after 24 hours. The MIC was defined as the lowest concentration inhibiting ≥90% bacterial growth [6]
- Cancer cell antiproliferation and apoptosis assay: HepG2 and MCF-7 cells were seeded in 96-well plates at 5×10³ cells/well and treated with Novobiocin Sodium (Albamycin; Cathomycin) at 5-80 μM for 72 hours. Cell viability was measured using a tetrazolium-based colorimetric assay. Apoptotic cells were detected by annexin V-FITC/PI double staining and flow cytometry; caspase-3 and PARP expression were analyzed by western blot [5]
- Cell cycle assay: HepG2 cells were treated with 25 μM Novobiocin Sodium (Albamycin; Cathomycin) for 24-48 hours. Cells were fixed with ethanol, stained with propidium iodide, and analyzed by flow cytometry to determine G1 phase arrest [5]

Female Swiss mice
100 or 200 mg/kg
s.c.

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Staphylococcus aureus sepsis mouse model: Female BALB/c mice (6-8 weeks old) were intravenously inoculated with a lethal dose of Staphylococcus aureus. Novobiocin Sodium (Albamycin; Cathomycin) was dissolved in sterile saline and administered intraperitoneally at 50 or 100 mg/kg/day for 5 days. Mice were monitored for survival for 7 days, and blood, liver, and spleen samples were collected to quantify bacterial load via colony counting [6]
- HepG2 xenograft mouse model: Nude mice (6-7 weeks old) were subcutaneously inoculated with 2×10⁶ HepG2 cells. When tumors reached 150 mm³, mice were randomly divided into control and treatment groups (n=6 per group). Novobiocin Sodium (Albamycin; Cathomycin) was dissolved in saline and administered intraperitoneally at 40 mg/kg twice weekly for 4 weeks. Tumor volume and body weight were measured every 3 days; tumors were harvested for histological analysis [5]

Absorption, Distribution and Excretion
Oral bioavailability is negligible. In a phase I clinical trial, patients with refractory cancer received VP-16 on days 1, 3, and 5. Antiemetics, including ondansetron and dexamethasone, were administered 60 minutes before VP-16 administration. Neomycin was administered orally 30 minutes before VP-16 administration, with doses progressively increased in consecutive patient groups according to a standard dose-escalation regimen. Treatment cycles were repeated every 4 weeks. Plasma concentrations of neomycin were determined by high-performance liquid chromatography during the first treatment cycle. A total of 33 patients received 69 treatment cycles. Eleven patients received an initial dose of VP-16 of 120 mg/m², of whom 3 experienced neutropenic fever. The VP-16 dose was reduced to 100 mg/m², and an additional 22 patients were enrolled. The dose range of novimycin is 3 to 9 g. When the dose of novimycin is at least 5.5 g, the plasma concentration is maintained at at least 150 μM for 24 hours.

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Biological half-life 6 hours. Novimycin was administered orally for 96 hours; cyclophosphamide 750 mg/m² was administered intravenously 48 hours later. A total of 65 treatment cycles were administered to 34 patients. …Of the 19 patients treated with doses of 4 g or higher daily, 18 achieved serum drug concentrations of 100 μg/ml or higher at steady state, consistent with concentrations observed in in vitro and in vivo experiments. In vivo, the half-life of neomycin in mice is 82 minutes, significantly shorter than the human half-life (6.0 hours).

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Absorption: Neopycin sodium (Albamycin; Cathomycin) is poorly absorbed after oral administration in humans and animals, with an oral bioavailability of approximately 20-30%. After oral administration of 50 mg/kg to mice, the peak plasma concentration (Cmax) reached 1.2-2.0 μg/ml within 2-4 hours [4]
- Distribution: The drug is mainly distributed in extracellular fluid and tissues, such as the liver, spleen and kidneys; it does not significantly penetrate the blood-brain barrier. The plasma protein binding rate is approximately 85-90% [4]
- Metabolism: It is mainly metabolized by the liver, and more than 70% of the drug is excreted unchanged [4]
- Excretion: It is mainly excreted by the kidneys, and 60-70% of the administered dose is excreted in the urine within 24 hours. The elimination half-life in mouse plasma is approximately 3-4 hours [4]

Protein Binding
95% Acute toxicity: The LD50 of novimycin sodium (Albamycin; Cathomycin) administered intraperitoneally in rats is approximately 500-600 mg/kg. Doses > 300 mg/kg can cause mild renal tubular epithelial cell damage and hepatic congestion [4] Gastrointestinal toxicity: After oral administration, at doses ≥ 100 mg/kg, animals experienced mild nausea, vomiting, and diarrhea (incidence 10-15%) [4] Hematologic toxicity: Animal studies showed no significant leukopenia or thrombocytopenia at therapeutic doses [5][6] Hypersensitivity: Rare rashes and fever were observed in mice at high doses (≥ 200 mg/kg), suggesting possible hypersensitivity [4]

[1]. J Biol Chem . 2000 Nov 24;275(47):37181-6.

[2]. Biochemistry . 2004 Jun 29;43(25):8217-29.

[3]. Mol Biochem Parasitol . 2005 May;141(1):57-69.

[4]. IUBMB Life . 2010 Mar;62(3):194-9.

[5]. Cell Physiol Biochem . 2014;33(3):670-80.

[6]. Int J Antimicrob Agents . 2010 Jun;35(6):544-9.

Novobiocin is a coumarin antibiotic extracted from Streptomyces niveus. It has dual functions: antibacterial activity, inhibition of DNA topoisomerase (ATP hydrolase) activity, as a metabolite of Escherichia coli, and hepatoprotective agent. It is a hexoside, monocarboxylic acid amide, monosaccharide derivative, hydroxycoumarin, ether, carbamate, and phenolic compound. It is the conjugate acid of novimycin (1-). Novemycin is an antibiotic compound derived from Streptomyces niveus. Its chemical structure is similar to that of coumarin. Novemycin binds to DNA gyrase, inhibiting the activity of adenosine triphosphate (ATPase). (Excerpt from Reynolds, Martindale Pharmacopoeia, 30th edition, p. 189) Novemycin sodium is the salt form of novimycin, initially approved in September 1964 for the treatment of serious infections caused by susceptible Staphylococcus aureus strains, especially when other less toxic antibiotics are unavailable. In 2009, the U.S. Food and Drug Administration (FDA) halted the sale of novimycin sodium due to safety and efficacy concerns. Novimycin is reportedly found in Streptomyces, Streptomyces leucopterus, and other microorganisms for which relevant data are available. Novimycin is an aminocoumarin antibiotic produced by the actinomycete Streptomyces niveus and possesses antibacterial activity. Like other aminocoumarin antibiotics, novimycin inhibits bacterial DNA synthesis by targeting bacterial DNA gyrase and its associated enzyme, DNA topoisomerase IV. This antibiotic has been used to treat Gram-positive bacterial infections. Novimycin is an antibiotic compound derived from Streptomyces niveus. Its chemical structure is similar to that of coumarins. Novimycin binds to DNA gyrase and blocks the activity of adenosine triphosphatase (ATPase). (Excerpt from Reynolds Martindale Pharmacopoeia, 30th edition, p. 189) See also: Novimycin sodium (salt form); Novimycin calcium (salt form). Indications For the treatment of infections caused by Staphylococcus and other susceptible bacteria. Mechanism of Action Novemycin is an aminocoumarin that acts by inhibiting the GyrB subunit of bacterial DNA gyrase, an enzyme involved in energy transduction. Similar to other aminocoumarin antibiotics, it acts as a competitive inhibitor of the GyrB-catalyzed ATPase reaction. Therapeutic Uses MeSH Title: Antimicrobial Agent, Enzyme Inhibitor Veterinary Drug: For the treatment of respiratory infections in dogs and the prevention of mastitis in dairy cows. Therapeutic Category: Antimicrobial. Therapeutic Category (Veterinary Drug): Antimicrobial Agent Novemycin is a narrow-spectrum antibiotic that may have bacteriostatic or bactericidal effects at high concentrations. It is primarily effective against Gram-positive bacteria, but also effective against a few Gram-negative bacteria. …Its primary use is in combination with other drugs for the treatment of bovine mastitis.

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Drug Warnings
Organ system complications associated with novimycin include: immune system—rash; gastrointestinal system: nausea, vomiting, diarrhea; hematologic system: pancytopenia, hemolytic anemia. /Excerpt from Table/

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Pharmacodynamics
Novimycin is an aminocoumarin antibiotic produced by the actinomycete Streptomyces niveus. Novimycin binds to DNA gyrase and blocks the activity of adenosine triphosphatase (ATPase). Other aminocoumarin antibiotics include coumarin A1 and chloramphenicol.

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Novacin sodium (leucomycin; captomycin) is the first naturally occurring coumarin antibiotic, isolated from Streptomyces niveus[1][4]
-Mechanism of action: It exerts its antibacterial effect by binding to the B subunit of bacterial DNA gyrase, inhibiting its ATPase activity, blocking DNA supercoiling, thereby inhibiting bacterial DNA replication/transcription. Antitumor effects involve G1 phase cell cycle arrest and induction of cancer cell apoptosis [2][5][6]
- Clinical indications: Historically used to treat infections caused by susceptible Gram-positive bacteria (e.g., methicillin-sensitive Staphylococcus aureus) and certain mycobacteria. Due to the widespread presence of bacterial resistance, its clinical application is currently limited [4][6]
- Resistance mechanism: Bacterial resistance originates from mutations in the gyrB gene (encoding the DNA gyrase B subunit), leading to reduced drug binding affinity [6]
- Therapeutic potential: Due to its low cross-resistance with conventional chemotherapy drugs, it has re-emerged as a candidate drug for combination cancer therapy [5]

C31H35N2NAO11

634.61

634.214

C, 58.67; H, 5.56; N, 4.41; Na, 3.62; O, 27.73

1476-53-5

303-81-1

54675769

White to off-white solid powder

1.42g/cm3

848.2ºC at 760mmHg

215-220ºC

466.8ºC

4.838

5

11

9

44

1150

4

[Na+].O1C([H])([C@]([H])(C([H])([C@]([H])(C1(C([H])([H])[H])C([H])([H])[H])OC([H])([H])[H])OC(N([H])[H])=O)O[H])OC1C([H])=C([H])C2C(=C(C(=O)OC=2C=1C([H])([H])[H])N([H])C(C1C([H])=C([H])C(=C(C([H])([H])/C(/[H])=C(\C([H])([H])[H])/C([H])([H])[H])C=1[H])[O-])=O)O[H]

WWPRGAYLRGSOSU-RNROJPEYSA-M

InChI=1S/C31H36N2O11.Na/c1-14(2)7-8-16-13-17(9-11-19(16)34)27(37)33-21-22(35)18-10-12-20(15(3)24(18)42-28(21)38)41-29-23(36)25(43-30(32)39)26(40-6)31(4,5)44-29;/h7,9-13,23,25-26,29,34-36H,8H2,1-6H3,(H2,32,39)(H,33,37);/q;+1/p-1/t23-,25+,26-,29-;/m1./s1

sodium;7-[(2R,3R,4S,5R)-4-carbamoyloxy-3-hydroxy-5-methoxy-6,6-dimethyloxan-2-yl]oxy-3-[[4-hydroxy-3-(3-methylbut-2-enyl)benzoyl]amino]-8-methyl-2-oxochromen-4-olate

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Solubility in Formulation 1: 100 mg/mL (157.58 mM) in PBS (add these co-solvents sequentially from left to right, and one by one), clear solution; with sonication (<60°C).

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 (Please use freshly prepared in vivo formulations for optimal results.)