Optical probe for the cytochrome P-450 cholesterol side chain cleavage enzyme

Patent · 01 January 1993

OSTI ID:868773

Marrone, Babetta L ^[1]; Simpson, Daniel J ^[1]; Unkefer, Clifford J ^[1]; Whaley, Thomas W ^[2]

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1. Los Alamos, NM
2. Santa Fe, NM

An optical probe enables the study of enzyme activity by absorbance spectroscopy or by sensitive fluorescence methods. In particular, the probe provides the ability to monitor the activity of cytochrome P-450.sub.scc enzyme, the rate limiting enzyme for steroid biosynthesis. Located on the inner mitochondrial membrane, P-450.sub.scc catalyzes the conversion of cholesterol to pregnenolone and isocapraldehyde by sequential oxidations of the cholesterol side chain. The fluorogenic probe includes a cholesterol-like steroid linked to a chromophore through a linking group. The chromophore is selected to have little optical response when linked to the steroid substrate and an enhanced optical response when cleaved from the substrate and linking group. Thus, a fluorescent anion that can be optically detected is generated by the side-chain cleavage reaction during steroidogenesis.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM
• DOE Contract Number: W-7405-ENG-36
• Assignee: United States of America as represented by United States (Washington, DC)
• Patent Number(s): US 5208332
• OSTI ID: 868773
• Country of Publication: United States
• Language: English

Related Subjects

/999/
ability
absorbance
absorbance spectroscopy
activity
anion
biosynthesis
catalyzes
chain
chain cleavage
cholesterol
cholesterol-like
chromophore
cleavage
cleavage enzyme
cleaved
conversion
cytochrome
cytochrome p-450
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enables
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optical
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optical response
optically
optically detected
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pregnenolone
probe
probe enables
probe provides
provides
rate
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response
scc
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sequential
side-chain
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steroid
steroidogenesis
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substrate