Serological evidence for the alteration of enolase during aging.

Pure enolase isolated from young and old Turbatrix aceti has been compared using immunologic techniques. Antiserum prepared to "young" and "old" enolase, respectively, will completely precipitate either enzyme. However, antiserum prepared to "young" enolase reacts more efficiency with "young" than with "old" than with "old" enzyme and vice versa. A third form of enolase (inactive enolase) is found in homogenates of old organisms. This material yields a pattern of identity with "young" enolase and partial identity with "old" enolase. It also gives rise to specific antibodies which do not react with "young" or "old" enolase. The material appears to accumulate with age. The results indicate a close structural relationship between "young", "old" and inactive enolase.