Kinetic and chemical analyses of the cytokinin dehydrogenase-catalysed reaction: correlations with the crystal structure

Result code in IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F61389030%3A_____%2F06%3A00325770" target="_blank" >RIV/61389030:_____/06:00325770 - isvavai.cz</a>

Result on the web

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DOI - Digital Object Identifier

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Result language

angličtina

Original language name

Kinetic and chemical analyses of the cytokinin dehydrogenase-catalysed reaction: correlations with the crystal structure

Original language description

CKX (cytokinin dehydrogenase) is a flavoprotein that cleaves cytokinins to adenine and the corresponding side-chain aldehyde using a quinone-type electron acceptor. In the present study, reactions of maize (Zea mays) CKX with five different substrates (N-6-isopentenyladenine, trans-zeatin, kinetin, p-topolin and N-methyl-isopentenyladenine) were studied. By using stopped-flow analysis of the reductive half-reaction, spectral intermediates were observed indicative of the transient formation of a binary enzyme-product complex between the cytokinin imine and the reduced enzyme. The reduction rate was high for isoprenoid cytokinins that showed formation of a charge-transfer complex of reduced enzyme with bound cytokinin imine. For the other cytokinins, flavin reduction was slow and no charge-transfer intermediates were observed. The binary complex of reduced enzyme and imine product intermediate decays relatively slowly to form an unbound product, cytokinin imine, which accumulates in the

Czech name

Kinetické a chemické analýzy reakce katalyzované cytokininoxidasou/dehydrogenasou: korelace s krystalovou strukturou

Czech description

Byly studovány reakce kukuřičné cytokininoxidasy/dehydrogenasy s pěti různými substráty (N6-isopentenyladenin, trans-zeatin, kinetin, p-topolin and Nmethyl-isopentenyladenin). Pomocí metody zastaveného toku byly spektrofotometricky sledovány reakční meziprodukty. Byla prokázána tvorba přechodného binárního komplexu mezi redukovaným enzymem a iminovým derivátem substrátu. Stabilita iminových produktů umožnila jejich strukturní analýzu pomocí hmotnostní spektrometrie.

Type

J_x - Unclassified - Peer-reviewed scientific article (Jimp, Jsc and Jost)

CEP classification

CE - Biochemistry

OECD FORD branch

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Project

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Continuities

Z - Vyzkumny zamer (s odkazem do CEZ)

Publication year

2006

Confidentiality

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Name of the periodical

Biochemical Journal

ISSN

0264-6021

e-ISSN

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Volume of the periodical

398

Issue of the periodical within the volume

1

Country of publishing house

GB - UNITED KINGDOM

Number of pages

12

Pages from-to

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UT code for WoS article

000239836100012

EID of the result in the Scopus database

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