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Fluorescence-based Monitoring of PAD4 Activity via a Pro-fluorescence Substrate Analog
Published on: November 5, 2014
Homodimer and heterodimer subunits of human prostate acid phosphatase
1Department of Diagnostic Immunology Research and Biochemistry, Roswell Park Memorial Institute, Buffalo, NY 14263.
The Biochemical Journal
|August 1, 1991
Summary
Human prostatic acid phosphatase (PAP) exists as two main isoenzymes, PAP-A and PAP-B. PAP-A is a homodimer, while PAP-B is a mix of heterodimers, revealing three distinct human PAP isoforms.
Area of Science:
- Biochemistry
- Enzymology
- Proteomics
Background:
- Human prostatic acid phosphatase (PAP) is a key enzyme found in seminal plasma.
- Understanding PAP isoenzymes is crucial for their diagnostic and functional roles.
Purpose of the Study:
- To isolate and characterize the distinct isoenzymes of human prostatic acid phosphatase (PAP).
- To elucidate the subunit composition and structural differences between PAP-A and PAP-B.
Main Methods:
- Sequential affinity chromatography using concanavalin A and L(+)-tartrate.
- Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for molecular mass determination.
- Reverse-phase high-performance liquid chromatography (RP-HPLC) for component analysis.
- Immunological characterization to assess antigenic differences.
Main Results:
- Two major human prostatic acid phosphatase (PAP) isoenzymes, PAP-A and PAP-B, were isolated.
- PAP-A is a homodimer (alpha 2), while PAP-B is a mixture of heterodimers (alpha beta and alpha gamma), indicating three isoforms.
- Both isoenzymes share similar molecular mass, pI, and inhibitor specificity but differ antigenically.
- PAP-B dissociates into 50 kDa subunits, while PAP-A remains intact at 100 kDa under high salt conditions.
Conclusions:
- Human prostatic acid phosphatase (PAP) comprises three isoforms: alpha 2, alpha beta, and alpha gamma.
- PAP-A represents a homodimeric structure, whereas PAP-B is a heterogeneous mixture of heterodimers.
- These structural differences contribute to the distinct properties of PAP isoenzymes.
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