With MIC values ranging from 0.06-0.25 μg/mL (MIC50 = 0.12 μg/mL, MIC90 = 0.25 μg/mL), mupirocin (BRL-4910A, pseudomonoic acid) calcium hydrate (0-100 μM; 48 h) exhibits antibacterial activity against staphylococci, streptococci, and some gram-negative bacteria[1]. The presence of human serum inhibits the activity of mugirocin calcium hydrate due to its strong 95% binding to human serum protein[1].
It appears that the antimicrobial activity of mugirocin calcium hydrate is achieved by reversibly inhibiting isoleucyl-transfer RNA, which in turn inhibits the synthesis of bacterial proteins and RNA[2].
Mupirocin calcium hydrate (2% ointment) decreases the expression of tumor necrosis factor-alpha (TNF-α), increases the leavel of vascular endothelial growth factor (VEGF), and decreases the levels of pro-inflammatory cytokines IL-1β and IL-17[4].
With MICs of 0.25, 1.26, and 1.59 mg/L, mugirocin calcium hydrate inhibits MS (S. epidermidis ATCC 12228), MR (S. epidermidis (Se56-99)), and VIR (S. epidermidis (Se43-98))[5].

MRSA: Staphylococcus aureus resistant to meticillin
Following oral and parenteral administration, mupirocin (BRL-4910A, pseudomononic acid) calcium is well absorbed; however, the prolonged breakdown of the antibiotic to the antibacterially inactive metabolite monic acid A resulted in short-lived serum antibiotic concentrations [1].
Using either topical treatment, mugirocin calcium (2% ointment; external administration; twice daily; 3-6 d) reduces the overall bacterial loads in the skin lesions[3].
Mice with pressure ulcers infected with MRSA are treated with 2% ointment of mupirocin calcium administered externally every 4 days[4].
Staphylococcus epidermidis-caused vascular prosthetic graft infection can be prevented with mugirocin calcium (100 mg/mL; s.c.; 7 d)[5].

Cell Line: Staphylococcus aureus
Concentration: 0-100 μM/mL
Incubation Time: 24, 48 hours
Result: produced a 90–99% reduction at 24 hours, with MIC and MBC values ranging from 0.12-1.0 μM/mL and 4.0–32 μM/mL, respectively, at 48 hours.

Animal Model: MRSA skin infection model in mice (10-12 weeks old)[3]
Dosage: 2% ointment
Administration: External administration; twice daily; 3-6 days
Result: decreased the overall amount of bacteria present in the skin lesions, with reductions of 2.0 and 5.1 log10 CFU on days three and six, respectively.

Absorption, Distribution and Excretion
Following transdermal administration in adults and children, systemic or transdermal absorption of mupirocin is expected to be minimal. Occlusive dressings do not significantly enhance drug absorption, but damaged skin may allow the drug to more easily penetrate the skin barrier. Any mupirocin that enters systemic circulation is rapidly metabolized to inactive monosodium monoxide and excreted via the kidneys. In 23 healthy volunteers, following once-daily application of 2% Centany (mupirocin ointment) to a 400 cm² area of the back for 7 consecutive days, the mean (range) cumulative excretion of monosodium monoxide in urine within 24 hours of the last dose was 1.25% (0.2% to 3.0%). No information available. No information available. Metabolism/Metabolites Following intravenous or oral administration, mupirocin is rapidly metabolized in the liver to the major metabolite monosodium monoxide, which has no antibacterial activity.

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Biological Half-Life
In healthy male volunteers, the elimination half-life of mupirocin after intravenous injection is approximately 20 to 40 minutes. The elimination half-life of monic acid is approximately 30 to 80 minutes.

Effects During Pregnancy and Lactation
◉ Overview of medication use during lactation
Mupirocin poses a low risk to breastfed infants due to its absorption rate of less than 1% after topical application. [1] Ensure that the infant's skin does not come into direct contact with the treated area. Only water-soluble creams or gels should be applied to the breast, as ointments may expose the infant to high concentrations of mineral oil through licking. [2] Topical application of mupirocin appears to be ineffective for nipple pain and cracking.
◉ Effects on breastfed infants
A mother of a 52-day-old exclusively breastfed infant developed a soft tissue infection. She received intravenous teicoplanin at 400 mg every 12 hours for 3 times, followed by 400 mg daily for 5 days; intravenous ceftriaxone 1 g daily; and topical mupirocin cream twice daily. Careful follow-up showed that her infant did not experience any adverse reactions. [3]
◉ Effects on breastfeeding and breast milk
A small, randomized, nonblinded trial of mothers with nipple pain and cracking showed that applying 2% mupirocin cream to the nipples after each feeding (16%) was far less effective than oral antibiotics (cloxacillin or erythromycin for 10 days) (79%). Furthermore, a higher percentage of patients using mupirocin experienced worsening of their condition compared to those using oral antibiotics (28% vs 5%). [4]
In a randomized, double-blind trial, researchers compared lanolin with a universal nipple ointment containing 1% mupirocin, 0.05% betamethasone, and 2% miconazole for the treatment of nipple pain during the first two weeks of breastfeeding postpartum. Both treatments were comparable in reducing nipple pain, shortening nipple healing time, prolonging breastfeeding duration, increasing exclusive breastfeeding rates, reducing mastitis and nipple symptoms, reducing side effects, or increasing maternal satisfaction with treatment. [5]

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Protein binding
It has been reported that mupirocin has a protein binding rate of over 95%.

[1]. Antibacterial activity of mupirocin (pseudomonic acid), a new antibiotic for topical use. Antimicrob Agents Chemother. 1985 Apr;27(4):495-8.

[2]. Mupirocin: a topical antibiotic with a unique structure and mechanism of action. Clin Pharm. 1987 Oct;6(10):761-70.

[3]. Efficacy of topical and systemic antibiotic treatment of meticillin-resistant Staphylococcus aureus in a murine superficial skin wound infection model. Int J Antimicrob Agents. 2013 Sep. 42(3):272-5.

[4]. Mohammad H, Abutaleb NS, Dieterly AM, Lyle LT, Seleem MN. Investigating auranofin for the treatment of infected diabetic pressure ulcers in mice and dermal toxicity in pigs. Sci Rep. 2021 May 25;11(1):10935.

[5]. Mupirocin prophylaxis against methicillin-susceptible, methicillin-resistant, or vancomycin-intermediate Staphylococcus epidermidis vascular-graft infection. Antimicrob Agents Chemother. 2000 Oct. 44(10):2842-4.

Mupirocin is an α,β-unsaturated ester formed by the condensation of the hydroxyl group of 9-hydroxynonanoic acid with the carboxyl group of (2E)-4-[(2S)-tetrahydro-2H-pyran-2-yl]-3-methylbut-2-enoic acid, wherein the 3- and 4-positions of the tetrahydropyran ring are substituted with hydroxyl groups, and the 5-position is substituted with {(2S,3S)-3-[(2S,3S)-3-hydroxybut-2-yl]ethyleneoxy-2-yl}methyl. It was initially isolated from the Gram-negative bacterium Pseudomonas fluorescens and used as a topical antibiotic to treat Gram-positive bacterial infections. It is both a bacterial metabolite and an antibacterial agent, and also has the effect of inhibiting protein synthesis. It is a monocarboxylic acid, belonging to the oxacyclohexane class of compounds, and is also an epoxide, secondary alcohol, triol, and α,β-unsaturated carboxylic acid ester. It is the conjugate acid of mupirocin (1-). Mupirocin, formerly known as Pseudomonas aeruginosa acid A, is a novel antibacterial agent with a unique chemical structure and mechanism of action, distinct from other antibiotics. Produced by the fermentation of Pseudomonas fluorescens, mupirocin is a naturally occurring antibiotic with broad-spectrum antibacterial activity against a wide range of Gram-positive and some Gram-negative bacteria in vitro. Its primary mechanism of action is the inhibition of bacterial protein synthesis. Due to its unique mechanism of action of inhibiting bacterial isoleucyl-tRNA synthetase activity, mupirocin does not exhibit cross-resistance with other antibacterial agents, giving it a therapeutic advantage. Because of its extensive systemic metabolism, mupirocin is only available in topical formulations for the treatment of impetigo caused by Staphylococcus aureus and Streptococcus pyogenes, as well as traumatic skin lesions caused by secondary skin infections of Staphylococcus aureus and Streptococcus pyogenes. Some clinical evidence suggests that intranasal administration of mupirocin may help clear staphylococci from the nasal cavity. A common brand name for mupirocin is Bactroban. Mupirocin is an RNA synthase inhibitor. Its mechanism of action is as an RNA synthase inhibitor. Mupirocin has been reported to exist in Pseudomonas fluorescens, and relevant data are available. Mupirocin is a natural crotonic acid derivative extracted from Pseudomonas fluorescens. Mupirocin inhibits bacterial protein synthesis by specifically and reversibly binding to bacterial isoleucine-tRNA synthetase. It has excellent activity against Gram-positive staphylococci and streptococci, and is mainly used to treat primary and secondary skin diseases, nasal infections, and promote wound healing. (NCI04) A topical antibiotic derived from Pseudomonas fluorescens. It exhibits excellent activity against Gram-positive staphylococci and streptococci. This antibiotic is mainly used to treat primary and secondary skin diseases, nasal infections, and wound healing.

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Drug Indications
Indications for the treatment of impetigo and secondary skin infections caused by Staphylococcus aureus and Streptococcus pyogenes, leading to traumatic skin lesions. Mechanism of Action Mupirocin specifically and reversibly binds to bacterial isoleucyl transfer RNA (tRNA) synthase, which promotes the conversion of isoleucine and tRNA to isoleucyl-tRNA. Inhibition of this enzyme, in turn, inhibits bacterial protein and RNA synthesis. Mupirocin exhibits antibacterial activity at low concentrations, but prolonged exposure can exert bactericidal effects, killing 90-99% of susceptible bacteria within 24 hours. Pharmacodynamics Mupirocin has been reported to be effective against susceptible aerobic Gram-positive cocci (such as Staphylococcus aureus and Staphylococcus epidermidis) and other β-hemolytic streptococci (such as Streptococcus pyogenes). Its antibacterial activity is achieved by inhibiting bacterial protein synthesis and the formation of proteins essential for bacterial survival. The minimum bactericidal concentration (MBC) against relevant pathogens is typically 8 to 30 times higher than the minimum inhibitory concentration (MIC). In a clinical study investigating the efficacy of topical mupirocin in treating impetigo, the response rate one week after treatment was approximately 94% to 98%. In clinical studies of patients with primary and secondary skin infections, over 90% of patients receiving topical mupirocin treatment demonstrated pathogen eradication and clinical symptom improvement. Mupirocin resistance rates as high as 81% have been previously reported. Mupirocin resistance is more common in methicillin-resistant Staphylococcus aureus (MRSA) than in methicillin-sensitive MRSA, and its development may be due to the production of a modified isoleucyl-tRNA synthetase or the acquisition of a plasmid mediating a novel isoleucyl-tRNA synthetase through gene transfer.

C52H90CAO20

1077.35288

1074.57

C, 58.08; H, 8.44; Ca, 3.73; O, 29.76

115074-43-6

Mupirocin;12650-69-0;Mupirocin calcium;104486-81-9

446596

White to off-white solid powder

672.3ºC at 760 mmHg

77-78
77 - 78 °C

216.5ºC

5.91E-21mmHg at 25°C

4.902

4

9

17

35

694

8

O.O.[Ca+2].OC(CCCCCCCCOC(/C=C(/CC1OCC(CC2OC2C(C(O)C)C)C(O)C1O)\C)=O)=O.OC(CCCCCCCCOC(/C=C(/CC1OCC(CC2OC2C(C(O)C)C)C(O)C1O)\C)=O)=O

DDHVILIIHBIMQU-YJGQQKNPSA-L

InChI=1S/2C26H44O9.Ca.2H2O/c2*1-16(13-23(30)33-11-9-7-5-4-6-8-10-22(28)29)12-20-25(32)24(31)19(15-34-20)14-21-26(35-21)17(2)18(3)27/h2*13,17-21,24-27,31-32H,4-12,14-15H2,1-3H3,(H,28,29)2*1H2/q+2/p-2/b2*16-13+/t2*17-,18-,19-,20-,21-,24+,25-,26-/m00.../s1

calcium 9-(((E)-4-((2S,3R,4R,5S)-3,4-dihydroxy-5-(((2S,3S)-3-((2S,3S)-3-hydroxybutan-2-yl)oxiran-2-yl)methyl)tetrahydro-2H-pyran-2-yl)-3-methylbut-2-enoyl)oxy)nonanoate dihydrate

Mupirocin calcium salt; Calcium Mupirocin Dihydrate; Mupirocin Calcium Hydrate

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 (e.g. under nitrogen), avoid exposure to moisture and light.

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

DMSO : ~100 mg/mL (~185.64 mM)

Solubility in Formulation 1: ≥ 1.25 mg/mL (2.32 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL.
Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution.

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Solubility in Formulation 2: ≥ 1.25 mg/mL (2.32 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly.
Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.

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Solubility in Formulation 3: ≥ 1.25 mg/mL (2.32 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution.
For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 12.5 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.

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