English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Royal palm tree peroxidase (RPTP) has been isolated to homogeneity from leaves of Roystonea regia palm trees. The enzyme purification steps included homogenization, (NH4)SO4 precipitation, extraction of palm leaf colored compounds and consecutive chromatography on Phenyl-Sepharose, TSK-Gel DEAE-5PW and Superdex-200. The novel peroxidase was characterized as having a molecular weight of 48.2 ± 3.0 kDa and an isoelectric point pI 5.4 ± 0.1. The enzyme forms dimers in solution with approximate molecular weight of 92 ± 2 kDa. Here we investigated the steady-state kinetic mechanism of the H2O2-supported oxidation of different organic substrates by RPTP. The results of the analysis of the initial rates vs. H2O2 and reducing substrate concentrations were seen to be consistent with a substrate-inhibited Ping-Pong Bi-Bi reaction mechanism. The phenomenological approach used expresses the peroxidase Ping-Pong mechanism in the form of the Michaelis-Menten equation and affords an interpretation of the effects in terms of the kinetic parameters KmH2O2, KmAH2, kcat, KSIH2O2, KSIAH2 and of the microscopic rate constants k1 and k3 of the shared three-step peroxidase catalytic cycle. Furthermore, the concentration and time-dependences and the mechanism of the suicide inactivation of RPTP by hydrogen peroxide were studied kinetically with guaiacol as co-substrate. The turnover number (r) of H2O2 required to complete the inactivation of the enzyme was 2154 ± 100 and the apparent rate constants of catalysis 185 s–1 and 18 s–1

Steady-state kinetics of &lt;i&gt;Roystonea regia&lt;/i&gt; palm tree peroxidase

Steady-state kinetics of <i>Roystonea regia</i> palm tree peroxidase