uncompetitive inhibition

• 不競合阻害、非拮抗的阻害

関

noncompetitive inhibition

WordNet

1. (physiology) the process whereby nerves can retard or prevent the functioning of an organ or part; "the inhibition of the heart by the vagus nerve"
2. (psychology) the conscious exclusion of unacceptable thoughts or desires (同)suppression
3. the quality of being inhibited
4. not inclined to compete

PrepTutorEJDIC

1. 禁止; 抑制; （心理学で）抑制; （化学で）（反応の）阻害, 抑制

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2016/12/01 20:37:48」(JST)

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Not to be confused with Non-competitive inhibition.

Uncompetitive inhibition, also known as anti-competitive inhibition, takes place when an enzyme inhibitor binds only to the complex formed between the enzyme and the substrate (the E-S complex).

While uncompetitive inhibition requires that an enzyme-substrate complex must be formed, non-competitive inhibition can occur with or without the substrate present.

Mechanism

This reduction in the effective concentration of the E-S complex increases the enzyme's apparent affinity for the substrate through Le Chatelier's principle (K_m is lowered) and decreases the maximum enzyme activity (V_max), as it takes longer for the substrate or product to leave the active site. Uncompetitive inhibition works best when substrate concentration is high. An uncompetitive inhibitor need not resemble the substrate of the reaction it is inhibiting.

Mathematical definition

Lineweaver–Burk plot of uncompetitive enzyme inhibition.

The Lineweaver–Burk equation states that:

$\ {\frac {1}{v}}={\frac {K_{m}}{V_{max}[S]}}+{1 \over V_{\max }}$

Where v is the initial reaction velocity, K_m is the Michaelis–Menten constant, V_max is the maximum reaction velocity, and [S] is the concentration of the substrate.

The Lineweaver–Burk plot for an uncompetitive inhibitor produces a line parallel to the original enzyme-substrate plot, but with a higher y-intercept, due to the presence of an inhibition term $\ {\frac {[I]}{K_{i}}}$:

$\ {\frac {1}{v}}={\frac {K_{m}}{V_{max}[S]}}+{\frac {1+{\frac {[I]}{K_{i}}}}{V_{max}}}$

Where [I] is the concentration of the inhibitor and K_i is an inhibition constant characteristic of the inhibitor.

Notes and references

UpToDate Contents

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English Journal

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• Allantoinase and dihydroorotase binding and inhibition by flavonols and the substrates of cyclic amidohydrolases.

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• Characterization of a thermostable 2,4-diaminopentanoate dehydrogenase from Fervidobacterium nodosum Rt17-B1.

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Japanese Journal

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• Inhibition of Aldose Reductase by Phenylethanoid Glycoside Isolated from the Seeds of Paulownia coreana

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• Biological & Pharmaceutical Bulletin 34(1), 160-163, 2011
• … In kinetic analyses performed using Lineweaver–Burk plots of 1/velocity and 1/concentration of substrate, isocampneoside II (3) showed uncompetitive inhibition against rhAR. …
• NAID 130000402282

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★リンクテーブル★

リンク元	「非拮抗的阻害」「反競合阻害」「不競合阻害」
関連記事	「inhibition」「uncompetitive」

「非拮抗的阻害」

　　[★]

英

noncompetitive inhibition、uncompetitive inhibition

関

不競合阻害、非競合的阻害、非競合的拮抗、非競合的抑制

「反競合阻害」

　　[★]

英

[[]]

同

uncompetitive inhibition

関

[[]]

同

uncompetitive inhibition

「不競合阻害」

　　[★]

英

uncompetitive inhibition

関

非拮抗的阻害

「inhibition」

　　[★]

• n.

• 1.抑止、抑制、阻止、禁止
• 2.抑止(阻止)するもの
• 3.(心理学)(衝動などの)抑制
• 4.(化)(化学反応の)抑制
• 5.(生物)(酵素の働きなどの)抑制、阻害

　 　 　 　

「uncompetitive」

　　[★]

• 不競合的な

関

uncompetitively