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Published on: September 14, 2014
Is the Paracoccus halodenitrificans ATPase a chimeric enzyme?
1Exobiology Branch, Ames Research Center, Moffett Field, CA 94035, USA.
FEMS Microbiology Letters
|June 15, 1996
Summary
Membranes from Paracoccus halodenitrificans contain an ATPase enzyme. This enzyme shows unusual inhibitor sensitivity, suggesting it may be a hybrid type.
Area of Science:
- Biochemistry
- Molecular Biology
- Microbiology
Background:
- Paracoccus halodenitrificans membranes possess an ATPase.
- This enzyme exhibits optimal activity in low-salt conditions.
Purpose of the Study:
- To characterize the ATPase from Paracoccus halodenitrificans.
- To investigate its unique inhibitor sensitivity profile.
Main Methods:
- Enzyme activity assays.
- Inhibitor sensitivity profiling using known ATPase inhibitors.
Main Results:
- The ATPase was most active without NaCl.
- It was inhibited by F1F0-ATPase inhibitors (azide, rhodamine 6G).
- It was also inhibited by vacuolar ATPase inhibitors (bafilomycin A1, concanamycin A, N-ethylmaleimide, p-chloromercuriphenylsulfonate).
Conclusions:
- The ATPase displays indiscriminate sensitivity to inhibitors of both F1F0-ATPases and vacuolar ATPases.
- This suggests the enzyme may be a hybrid.
- Inhibitor-based diagnostics should be used cautiously for ATPase classification.
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