Overview
Puromycin is an aminonucleoside antibiotic originally derived from Streptomyces alboniger. It acts as a protein synthesis inhibitor by mimicking aminoacyl-tRNA, causing premature chain termination during translation. This mechanism makes it invaluable in molecular biology for selecting cells that have successfully incorporated foreign DNA (e.g., plasmids containing puromycin resistance genes). First isolated in the 1950s, puromycin has become a standard tool in research laboratories worldwide. Its ability to quickly and effectively halt protein synthesis makes it particularly useful for studying translation mechanisms and cellular responses to protein synthesis inhibition.
Physical and Chemical Properties
Puromycin appears as a white to off-white crystalline powder that is stable under recommended storage conditions but may degrade when exposed to light or moisture. The dihydrochloride salt form (CAS 58-58-2) is more commonly used due to its higher solubility in aqueous solutions compared to the free base (CAS 53-79-2). The compound shows good solubility in water (up to 50 mg/mL), methanol, and DMSO, but is less soluble in other organic solvents. Its molecular structure contains both nucleoside and amino acid-like components, which enable its unique mechanism of action by mimicking tyrosyl-tRNA.
Main Applications
In research settings, puromycin serves primarily as a selection agent in cell culture systems. Cells engineered to express puromycin N-acetyl-transferase (PAC) can survive in media containing puromycin, allowing researchers to selectively grow only transfected cells. Typical working concentrations range from 1-10 μg/mL depending on cell type. Beyond selection, puromycin is used to study protein synthesis dynamics, ribosome function, and cellular stress responses. It has also found applications in creating stable cell lines, studying autophagy, and investigating antibiotic resistance mechanisms. In some cases, puromycin is conjugated to other molecules to create cell-permeable inhibitors.
Safety and Storage
Puromycin is toxic and should be handled with appropriate personal protective equipment including gloves, lab coat, and eye protection. It may cause irritation to skin, eyes, and respiratory tract. Proper storage at -20°C in a tightly sealed container protected from light and moisture is essential for maintaining stability. Solutions of puromycin should be prepared under sterile conditions and can be filter-sterilized. Working solutions are typically stable for several weeks when stored at 4°C. For long-term storage, aliquots should be kept frozen at -20°C or below. Disposal should follow institutional guidelines for hazardous chemical waste.
B2B Procurement Guide
When procuring puromycin for research purposes, key considerations include purity (typically ≥98% for most applications), salt form (dihydrochloride is most common), and supplier reliability. Bulk quantities for industrial applications may require additional quality certifications. Documentation should include certificates of analysis with HPLC purity data, mass spectrometry confirmation, and endotoxin levels when relevant for cell culture applications. Lead times may vary depending on source and quantity, with research-grade material typically available from stock at major suppliers. For large-scale purchases, consider requesting samples for quality verification before committing to bulk orders.