The use of 2,4-dinitro-5-fluoroaniline in the determination of protein structure on a micro scale

✍ Scribed by Ronald S. Ratney; Miriam Fredrica Godshalk; Joan Joice; Kenni Ward James

• Publisher: Elsevier Science
• Year: 1967
• Tongue: English
• Weight: 536 KB
• Volume: 19
• Category: Article
• ISSN: 0003-2697
• DOI: 10.1016/0003-2697(67)90172-8

✦ Synopsis

Sanger's DNP method for the determination of N-terminal groups in proteins and peptides (1) has been widely used since its introduction, but in order to improve the sensitivity, E. Bergmann (2) developed a new reagent, 2,4-dinitro-5fluoroaniline.

This compound reacts with free amino groups in proteins, peptides, and amino acids to yield N-2,4-dinitro-5aminophenyl (DNAP) derivatives. These compounds are yellow like the corresponding DNP derivatives but their absorption maximum is at 410 my (2) compared with 350 rnp (3) for the DNP derivatives. Since this is further into the region of the spectrum visible to the human eye, the compounds are more readily seen (e.g., on chromatograms).

Also, the derivatives contain free aromatic amino groups which can be diazotized and coupled with phenols, etc. to form azo dyes that absorb light strongly at 425 and 610 rnp (2) and are thus even more visible.

This paper reports some work aimed at the exploitation of 2,4-dinitro-5-fluoroaniline as a reagent for the determination of N-terminal groups in proteins and peptides on an ultramicro scale. MATERIALS Amino acids were purchased from Nutritional Biochemicals Corp. 2,4-Dinitrod-fluoroaniline was purchased from Pierce Chemical Co.