• Erythromycin packaged and labeled.

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SKU: E002

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Erythromycin is a broad-spectrum macrolide antibiotic derived from Saccharopolyspora erythraea (formerly Streptomyces erythraeus) that inhibits bacterial protein synthesis.  It is composed largely of Erythromycin A, with small amounts of Erythromycin B and C.  It is typically used at a concentration of 100 mg/L.  Erythromycin is soluble in ethanol, 2M HCl (50 mg/ml), but sparingly soluble in aqueous solution (2 mg/mL). 

For other Erythromycin products, click here.

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    Mechanism of Action

    Macrolide antibiotics inhibit bacterial growth by targeting the 50S ribosomal subunit preventing peptide bond formation and translocation during protein synthesis. Resistance to Erythromycin is commonly attributed to mutations in 50S rRNA preventing erythromycin binding allowing the cell to synthesize proteins free of error.

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    Erythromycin is a broad spectrum antibiotic targeting Gram-negative and Gram-positive bacteria. It is also effective against Mycoplasma (ie M. pneumoniea), Mycobacteria, and spirochetes.


    Cancer Applications

    HERG (Human Ether-a-go-go Related Gene) may serve as a molecular marker and modulating target for individualized cancer therapy. Erythromycin, active as modulator and a HERG K+ channel blocker, suppressed the growth of various cancer cells and the potency was correlated with HERG expression levels. Erythromycin also enhanced the G2/M arrest induced by vincristine in HT-29 cells. (Chen et al, 2005).

    Eukaryotic Cell Culture Applications

    There is growing evidence that Erythromycin has anti-inflammatory properties and can be used to ameliorate airway inflammation. Using adult human T-cell leukemic cell line (Jurkat; clone E6-1), researchers found that the erythromycin could inhibit cytokine gene expression (specifically IL-8 gene) in T-cells and this mechanism is at the level of transcriptional regulation (Aoki and Kao, 1999).

    Erythromycin A is a potent stimulator of gastrointestinal motor activity. In vitro studies suggest that it mimics motilin, a peptide that stimulates motor activity in human and in rabbit via smooth muscle receptors (Peeters et al, 1989).

    The anti-inflammatory action of Erythromycin was evaluated by looking at isolated neutrophils from human blood. When erythromycin was applied, it shortened neutrophil survival in a dose-dependent way, with maximum effect at 10 mg/ml and above. It shortens neutrophil survival in part through elevating cAMP (cyclic AMP) levels. The result was accelerated apoptosis. Apoptosis may limit tissue injury by marking senescent neutrophils for phagocytosis and degradation by macrophages and by inhibiting the capacity of neutrophils to make injurious responses to inflammatory mediators (Aoshiba et al, 1995).

    Microbiology Applications

    Erythromycin is commonly used in clinical in vitro microbiological antimicrobial susceptibility tests (panels, discs, and MIC strips) against Gram-positive, Gram-negative, and Mycoplasma species.  Medical microbiologists use AST results to recommend antibiotic treatment options for infected patients.  Representative MIC values include:

    • Mycoplasma pneumoniae 0.0019 µg/mL – 0.0078 µg/mL
    • Legionella pneumophila 0.008 µg/mL – 1 µg/mL
    • For a  complete list of erythromycin MIC values, click here.

    Plant Biology Applications

    Erythromycin has been used in combination with nystatin and streptomycin for eliminating contaminants in rubber (Hevea brasiliensis) tissue culture (Leiffert et al.) (1991).





    White powder


    Biosynthetic: Saccharopolyspora erythraea (formerly Streptomyces erythraeus).

    Impurity Profile

    Erythromycin A||7540-22-9|C37H67NO13|733.93| Erythromycin B| 12-deoxy erythromycin|527-75-3|C37H67NO12|717.9| Erythromycin C| 3"-o-demethyl erythromycin A|1675-02-1|C36H65NO13|720.92| Erythromycin D| 3"-o-demethyl-12-deoxy erythromycin A||C36H65NO12|703.45| Impurity A| Erythromycin F|82230-93-1|C37H67NO14|749.46| Impurity B| N-demethyl erythromycin A|992-62-1|C36H65NO13|719.91| Impurity C| Erythromycin E|41451-91-6|C37H65NO14|747.91| Impurity D| Anhydroerythromycin A|23893-13-2|C37H65NO12|715.91| Impurity E| Erythromycin A enol ether|33396-29-1|C37H65NO12|715.91|

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    Optical Rotation

    -71° to -78°


    (On Dried Basis): 85-100.5%



    Aoki Y and Kao PN (1999)  Erythromycin inhibits transcriptional activation of NF-kappaB, but not NFAT, through calcineurin-independent signaling in T cells.  Antimicrob. Agents Chemother. 43(11):2678-2684 PMID 10543746

    Aoshiba K, Nagai A, and Konno K (1995) Erythromycin Shortens Neutrophil Survival by Accelerating Apoptosis. Antimicrob. Agents and Chemother. 39(4):872-877 PMID 7785987

    Chen S, Jiang M and Zhen Y (2005) HERG K+ channel expression-related chemosensitivity in cancer cells and its modulation by erythromycin. Cancer Chemother Pharmacol 56: 212-220.  PMID 15812674 

    Lovmar M and Tenson T (2003) The Mechanism of Action of Macrolides, Lincosamides and Streptogramin B Reveals the Nascent Peptide Exit Path in the Ribosome. Molec. Microbiol 330(5 ):1005-1014  PMID 12860123

    Leifert C, Ritchie JY and Waites WM (1991) Contaminants of plant-tissue and cell cultures. World J. Microbiol. Biotechnol. 7: 452469

    Oliynk M et al (2007)  Complete genome sequence of the erythromycin-producing bacterium Saccharopolyspora erythraea NRRL233338. Nature Biotechnol. 25:447-453 PMID 17369815 

    Peeters T et al (1989) Erythromycin is a motilin receptor agonist. Am. J. Physiol 257 (3):G470-G474  PMID 2782416


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