Preparation, purification, and structure elucidation of slow-reacting substance of anaphylaxis from guinea pig lung.
The work that we have described had originally three main aims: (a) to design a new purification system for SRS-A from which we would obtain pure material for the structural analysis: (b) to define the functional groups in the pure material by spectrophotometric, chemical, and enzymic inactivation methods; and (c) to deduce the complete covalent structure by an accepted spectroscopic method capable of defining structure in atomic detail. These aims have been achieved. The structure of SRS-A, the physiologically more relevant example of the SRSs that were studied, because it was derived immunologically from an animal model of an acute hypersensitivity reaction, has been rigorously defined. Of paramount importance in the determination of this structure was the mass spectrometric analysis of the intact molecule. Degradative and comparative studies are not capable of unequivocally defining structure. For example, the mass spectrum clearly showed the absence of an amide or similar C-terminal blocking groups or, as has been suggested, a sulfone in the molecule; such conclusions could not be drawn from comparative chromatographic data even on multiple systems. Mass spectrometric analysis of the intact molecule could overcome these problems by allowing the complete covalent structure to be collated from the information obtained from each fragmentation. The use of stable isotopes and accurate mass measurement removed possible ambiguities in the interpretation, and the sensitivity and specificity of mass spectrometry made it the method of choice for the structural analysis.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D002851:Chromatography, High Pressure Liquid; D006168:Guinea Pigs; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects; D013189:SRS-A / Q000302:isolation & purification* / Q000494:pharmacology
D013189:SRS-A