Merck, E5389-5G, Erythromycin

General description
Chemical structure: macrolide
Erythromycin is an antibiotic produced by growth of certain strains of Streptomyces erythreus. This product is composed largely of erythromycin A with small amounts of erythromycins B and C and is recommended for concentration at 100 mg/L. Concentrations between 50 and 200 mg/L have also proven effective in controlling bacterial growth. Erythromycin has been used as a motilin receptor agonist, to block respiratory glycoconjugate secretion in human airways in vitro, and for selecting plasmid-cured and recombinant lactococcus lactis MG1363 strains.
Application
Erythromycin has been used:
as a supplement for nutrient broth medium for culturing green fluorescent protein (GFP)- expressing E. coli
as a model drug to determine small intestinal (SMI) microtissue viability using the MTT assay{254
as an antibiotic to study the treatment strategies of chronic infections

Biochem/physiol Actions
Mode of Action: Erythromycin acts by inhibiting elongation at the transpeptidation step, specifically aminoacyl translocation from the A-site to P-site by binding to the 50s subunit of the bacterial 70s rRNA complex.

Antimicrobial Spectrum: This product acts against both gram-negative and gram-positive bacteria.
Preparation Note
This product is soluble in water at 2 mg/mL, with a 0.067% solution in water yielding a pH of 8.0-10.5. It is also soluble in ethanol at 50 mg/mL, yielding a clear, colorless to faint yellow solution. It is freely soluble in alcohol, acetone, chloroform, acetonitrile and ethyl acetate but forms salts with acids. All solutions should be protected from light.
Disclaimer
This product is stable in solution at 37°C for 3 days. Stock solutions should be stored at 2-8°C.