antibiotic puromycin ----an inhibitor of protein synthesis

Antibiotic Puromycin

----An inhibitor of protein synthesis

Ping Jiang

03-05-2000

Outline

• Discovery and Properties

• Structure and Functions

• Molecular Mechanism of Action

• Analogues and Synthesis

• Applications and Prospect

In 1952, the new antibiotic, Puromycin , isolated from the mold Streptomyces alboniger, has been found to be active against certain bacteria and Trypanosomes in Lederle laboratories division, American Cyanamid Company during the course of their antibiotic-screening program. One year later, the structure of puromycin was determined.

Discovery

Antibiotics and Chemotherapy, 1952, 2, 409

J. Am. Chem. Soc., 1953, 75, 2025

Chemical Properties

Formula: C22H29N7O5, 2HCl;

MW: 544.2

pKa: 6.8 and 7.2

http://www.cayla.com/support/datasheets/protect.htm

Puromycin is suitable for research purposes only.It must not be used on humans.

Structure

Puromycin: a structural and a functional analogue of

3’ terminus of aminoacyl-tRNA

The Ribosome: Structure, Function, and Evolution. 1990

Functions

Many antibiotics target the ribosome.

Puromycin tricks the ribosome into incorporating itself into the growing polypeptide chain causing premature termination, acting as an inhibitor of peptidyl transferase.

The antibiotic inhibits the growth of Gram positive bacteria and various animal and insect cells. Fungi and Gram negative are resistant due to the low permeability of the antibiotic

Problem: it kills eukaryotics and prokaryotics alike

RNA, 2000, 6, 744-754; Inhibitors of Protein Synthesis, 1979

Binding

TranspeptidationTranslocation

Mechanism:

Mechanism:

puro

A siteP site

Nascent

ProteinRelease

5’

mRNAStopcoden

Ribosome

tRNA

Nature,1963, 197, 1067-1977; FEBS Lett., 1997, 406, 223-233

Mechanism:

The Molecular Basis of Antibiotic Action, 1972, 412

Analogues and Synthesis:

A rich array of puromycin analogues with modified amino acid, carbohydrate, and/or base moieties has been prepared and evaluated biologically to study the structure-activity correlations…..

Puromycin (1) and the N-acetylglucosaminyl asparagine-substitued puromycin analogue 2a-c

Analogues and Synthesis:

Bioorg. & Medicinal Chem., 1995, 3, 1631-1636

Analogues and Synthesis:

J. Org. Chem., 2001, 66, 8204-8210

Applications and Prospect:

Puromycin has been widely used as a basic tool for studying protein synthesis.

Now, puromycin hydrochloride is particularly useful for the selection of cell types harbouring plasmids carrying puromycin resistance genes.

The specific bonding of puromycin to full-length protein at the C-terminus at a low concentration is potentially useful to the analysis of various biological phenomena.

Nucleic Acid Research, 2000, 28, 1176-1182

Application and Prospect:

puro

A siteP site

Release

5’

mRNA Stopcoden

Ribosome

tRNA

Full lengthProtein

Nucleic Acid Research, 2000, 28, 1176-1182