Characterization of "Peak E," a Novel Amino Acid Associated with Eosinophilia-Myalgia Syndrome

• Published in: Science (American Association for the Advancement of Science) 1990-12, Vol.250 (4988), p.1707-1708
• Main Authors: Mayeno, Arthur N., Lin, Feng, Foote, Christopher S., Loegering, David A., Ames, Matthew M., Hedberg, Craig W., Gleich, Gerald J.
• Format: Article
• Language: English
• Subjects: Amino acids; Biochemistry; Biological and medical sciences; Causes of; Chemical equilibrium; Chromatography, High Pressure Liquid; Drug toxicity and drugs side effects treatment; Eosinophilia - chemically induced; Eosinophilia myalgia syndrome; Health aspects; Humans; Hydrolysis; Indoles; Ingestion; Magnetic Resonance Spectroscopy; Medical sciences; Molecular Structure; Muscles; Nitrogen; Nuclear magnetic resonance; Pain - chemically induced; Pharmacology. Drug treatments; Spectrometry, Mass, Fast Atom Bombardment; Syndrome; Toxicity: nervous system and muscle; Tryptophan; Tryptophan - analogs & derivatives; Tryptophan - isolation & purification; Tryptophan - toxicity
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.2270484

Epidemiologic studies strongly associate eosinophilia-myalgia syndrome (EMS) with ingestion of tryptophan containing a contaminant ("peak E"). Prior reports have suggested that peak E is the di-tryptophan Nα-aminal of acetaldehyde. Spectral and chemical studies now demonstrate that peak E is 1,1′-ethylidenebis[tryptophan]. This novel amino acid may be the etiological agent responsible for EMS, or it may be a marker of a still unidentified causal agent.