Related Experiment Videos
Ananain: a novel cysteine proteinase found in pineapple stem
A D Rowan1, D J Buttle, A J Barrett
1Department of Biochemistry, Strangeways Research Laboratory, Worts Causeway, Cambridge, United Kingdom.
Archives of Biochemistry and Biophysics
|November 15, 1988
Summary
Researchers discovered ananain, a new cysteine proteinase from pineapple stems, distinct from bromelain in substrate specificity and inhibition. This finding impacts the interpretation of prior "bromelain" research.
Area of Science:
- Biochemistry
- Enzymology
- Proteomics
Background:
- Pineapple stem extracts contain proteinases, commonly referred to as bromelain.
- The exact composition and diversity of these proteinases are not fully elucidated.
- Previous studies may have overlooked distinct enzymatic entities within these extracts.
Purpose of the Study:
- To isolate and characterize a previously unknown cysteine proteinase from crude pineapple stem bromelain.
- To differentiate this new enzyme from the well-known bromelain.
- To clarify the enzymatic composition of pineapple stem extracts.
Main Methods:
- Affinity chromatography using Sepharose-Gly-Phe-glycinaldehyde semicarbazone.
- Cation-exchange chromatography for protein purification.
- Enzyme specificity assays and inhibition studies with chicken cystatin.
- Immunological distinctness assays.
Main Results:
- Isolation of a novel cysteine proteinase, named ananain.
- Ananain exhibits similar molecular mass to bromelain but significantly different substrate specificity.
- Ananain is strongly inhibited by chicken cystatin, unlike bromelain.
- Ananain is immunologically distinct from bromelain.
Conclusions:
- Ananain is a distinct cysteine proteinase present in pineapple stem extracts.
- The discovery of ananain necessitates a re-evaluation of previous research attributed solely to bromelain.
- Understanding ananain's unique properties is crucial for accurate biochemical and biotechnological applications.