PURIFICATION AND PROPERTIES OF AN IMINOPEPTIDASE FROM CULTURE MEDIA OF STREPTOMYCES-PLICATUS

The degradation of the prosequence of the secreted enzyme endo-β-Nacetylglucosaminidase H from Streptomyces plicatus is not elucidated. Both the primary structure of this segment and the finding that the secreted species contain ragged aminoterminal ends of specific structure suggested that a dipeptidylaminopeptidase might mature this enzyme. Therefore, we tested the culture medium of Streptomyces plicatus for prolin-specific peptidases. Proline iminopeptidase was purified about 800-fold to homogeneity from the culture medium. Dipeptidylaminopeptidase, the enzyme that seemed most likely to process the prosequence of endo-β-N-acetylglucosaminase H, could not be detected. © 1992 Academic Press, Inc.