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Updated: Oct 20, 2025
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Characterizing Individual Protein Aggregates by Infrared Nanospectroscopy and Atomic Force Microscopy
Published on: September 12, 2019
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Enzyme aggregation and fragmentation induced by catalysis relevant species
Kayla Gentile1, Ashlesha Bhide1, Joshua Kauffman1
1Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA. asen@psu.edu.
Physical Chemistry Chemical Physics : PCCP
|September 13, 2021
Summary
Enzymes may change structure during catalysis, fragmenting or aggregating with substrates or ions. This protein structural change does not necessarily impact enzyme activity, challenging native enzyme assumptions.
Area of Science:
- Biochemistry
- Enzymology
- Structural Biology
Background:
- Enzymes are typically assumed to maintain their native structure during catalytic processes.
- Protein aggregation and fragmentation can occur but are often challenging to detect, potentially leading to inaccurate conclusions about enzyme form.
Purpose of the Study:
- To investigate whether three model enzymes (alkaline phosphatase, hexokinase, glucose oxidase) undergo structural changes during catalysis.
- To determine if these structural changes affect enzyme activity.
Main Methods:
- Utilized multiple independent techniques to monitor enzyme structure.
- Examined alkaline phosphatase (AkP), hexokinase (HK), and glucose oxidase (GOx) in the presence of specific catalytic-related chemical species.
Main Results:
- Glucose oxidase and hexokinase fragmented with D-glucose, but not L-glucose.
- Hexokinase aggregated with Mg2+ and ATP/ADP at low pH.
- Alkaline phosphatase aggregated with Zn2+ and inorganic phosphate.
- Observed aggregation of hexokinase and alkaline phosphatase did not reduce their catalytic activity.
Conclusions:
- Specific multimeric structures of native enzymes may not be conserved during catalysis.
- Enzymes can undergo aggregation or fragmentation in response to substrates or cofactors.
- These structural dynamics suggest potential pathways for enzyme association and dissociation during substrate turnover.
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