Proteinase inhibitors I and II from leaves of wounded tomato plants: Purification and properties

  • Plunkett G
  • Senear D
  • Zuroske G
 et al. 
  • 4


    Mendeley users who have this article in their library.
  • 100


    Citations of this article.


Proteinase inhibitors I and II were purified to electrophoretic homogeneity from leaves of tomato plants induced by either wounding intact plants or by supplying excised plants with the proteinase inhibitor inducing factor. Affinity chromatography with chymotrypsin-Sepharose was employed as a final purification step for each inhibitor. The tomato leaf inhibitors are very similar to potato tuber inhibitors I and II in subunit molecular weight, composition, and inhibitory activities against chymotrypsin, trypsin, and subtilisin. However, unlike the potato tuber which contains multiple isoinhibitors by isoelectric focusing, the tomato leaf exhibits only two isoinhibitor forms of inhibitor I and a single form of inhibitor II. The molecular weight of native potato inhibitor I was reevaluated by rigorous ultracentrifugal analysis and compared with data from previous analyses. The data confirm that native inhibitor I has a native Mrof about 41,000 and is a pentamer. Inhibitor II has a molecular weight of near 23,000 and is a dimer. © 1982.

Get free article suggestions today

Mendeley saves you time finding and organizing research

Sign up here
Already have an account ?Sign in

Find this document


  • Gregory Plunkett

  • Donald F. Senear

  • Glen Zuroske

  • Clarence A. Ryan

Cite this document

Choose a citation style from the tabs below

Save time finding and organizing research with Mendeley

Sign up for free