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Solubilized elastin substrate for continuous fluorimetric assay of kinetics of elastases.

ABSTRACT: Elastolysis is central to progression of emphysema and aortic aneurysms. Characterization of steady-state enzyme kinetics of elastolysis is fettered by the insolubility of mature elastin and the polydispersity of solubilized elastin. We prepared a fluor-tagged, 100-kDa fraction (fEln-100) from commercial ?-elastin. It is soluble, less heterogeneous in mass, cross-linked like mature elastin, and likely to retain the capacity of ?-elastin to self-assemble. fEln-100 has introduced the ability to compare quantitatively the apparent k(cat) and K(m) of elastases. For example, metalloelastase (MMP-12) displays higher apparent affinity for fEln-100, while MMP-2 displays faster catalytic turnover.

SUBMITTER: Palmier MO

PROVIDER: S-EPMC2964420 | biostudies-literature | 2011 Jan

REPOSITORIES: biostudies-literature

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Solubilized elastin substrate for continuous fluorimetric assay of kinetics of elastases.

Palmier Mark O MO Fulcher Yan G YG Van Doren Steven R SR

Analytical biochemistry 20100907 1

Elastolysis is central to progression of emphysema and aortic aneurysms. Characterization of steady-state enzyme kinetics of elastolysis is fettered by the insolubility of mature elastin and the polydispersity of solubilized elastin. We prepared a fluor-tagged, 100-kDa fraction (fEln-100) from commercial α-elastin. It is soluble, less heterogeneous in mass, cross-linked like mature elastin, and likely to retain the capacity of α-elastin to self-assemble. fEln-100 has introduced the ability to co ...[more]

PMID: 20828532

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