Edman degradation

Revision as of 17:03, 4 September 2012 by WikiBot (talk | contribs) (Robot: Automated text replacement (-{{WikiDoc Cardiology Network Infobox}} +, -<references /> +{{reflist|2}}, -{{reflist}} +{{reflist|2}}))
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to: navigation, search

WikiDoc Resources for Edman degradation

Articles

Most recent articles on Edman degradation

Most cited articles on Edman degradation

Review articles on Edman degradation

Articles on Edman degradation in N Eng J Med, Lancet, BMJ

Media

Powerpoint slides on Edman degradation

Images of Edman degradation

Photos of Edman degradation

Podcasts & MP3s on Edman degradation

Videos on Edman degradation

Evidence Based Medicine

Cochrane Collaboration on Edman degradation

Bandolier on Edman degradation

TRIP on Edman degradation

Clinical Trials

Ongoing Trials on Edman degradation at Clinical Trials.gov

Trial results on Edman degradation

Clinical Trials on Edman degradation at Google

Guidelines / Policies / Govt

US National Guidelines Clearinghouse on Edman degradation

NICE Guidance on Edman degradation

NHS PRODIGY Guidance

FDA on Edman degradation

CDC on Edman degradation

Books

Books on Edman degradation

News

Edman degradation in the news

Be alerted to news on Edman degradation

News trends on Edman degradation

Commentary

Blogs on Edman degradation

Definitions

Definitions of Edman degradation

Patient Resources / Community

Patient resources on Edman degradation

Discussion groups on Edman degradation

Patient Handouts on Edman degradation

Directions to Hospitals Treating Edman degradation

Risk calculators and risk factors for Edman degradation

Healthcare Provider Resources

Symptoms of Edman degradation

Causes & Risk Factors for Edman degradation

Diagnostic studies for Edman degradation

Treatment of Edman degradation

Continuing Medical Education (CME)

CME Programs on Edman degradation

International

Edman degradation en Espanol

Edman degradation en Francais

Business

Edman degradation in the Marketplace

Patents on Edman degradation

Experimental / Informatics

List of terms related to Edman degradation


Overview

Edman degradation, developed by Pehr Edman, is a method of sequencing amino acids in a peptide. In this method, the amino-terminal residue is labeled and cleaved from the peptide without disrupting the peptide bonds between other amino acid residues.

Mechanism for Edman Degradation

Phenylisothiocyanate is reacted with an uncharged terminal amino group, under mildly alkaline conditions, to form a phenylthiocarbamoyl derivative. Then, under acidic conditions, this derivative of the terminal amino acid is cleaved as a thiazolinone derivative. The thiazolinone amino acid is then selectively extracted into an organic solvent and treated with acid to form the more stable phenylthiohydantoin (PTH)- amino acid derivative that can be identified by using chromatography or electrophoresis. This procedure can then be repeated again to identify the next amino acid. A major drawback to this technique is that the peptides being sequenced in this manner cannot have more than 50 to 60 residues. This is because the Edman degradation reaction is not 100% efficient, meaning that the cleavage step does not occur every time. However, this problem can be resolved by cleaving large peptides into smaller peptides before proceeding with the reaction. It is able to accurately sequence up to 30 amino acids with 98% efficiency per amino acid. An advantage of the Edman degradation is that it only uses 10 - 100 picomoles of peptide for the sequencing process. Edman degradation reaction is automated to speed up the process. [1]

Bergmann Degradation

An older related method for the stepwise degradation of polypeptides involving azides is the Bergmann Degradation [2] [3].

References

  1. Automated Edman degradation: the protein sequenator. Methods Enzymol. 1973;27:942-1010.
  2. M. Bergmann, Science 79, 439 (1934)
  3. drugfuture.com Link

de:Edman-Abbau



Linked-in.jpg