Linked Life Data

2271536

Source:http://linkedlifedata.com/resource/pubmed/id/2271536

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
37
pubmed:dateCreated
1991-2-27
pubmed:abstractText
Lignin peroxidase (LiP), an extracellular heme enzyme from the lignin-degrading fungus Phanerochaete chrysosporium, catalyzes the H2O2-dependent oxidation of a variety of nonphenolic lignin model compounds. The oxidation of monomethoxylated lignin model compounds, such as anisyl alcohol (AA), and the role of veratryl alcohol (VA) in LiP reactions were studied. AA oxidation reached a maximum at relatively low H2O2 concentrations, beyond which the extent of the reactions decreased. The presence of VA did not affect AA oxidation at low molar ratios of H2O2 to enzyme; however, at ratios above 100, the presence of VA abolished the decrease in AA oxidation. Addition of stoichiometric amounts of AA to LiP compound II (LiPII) resulted in its reduction to the native enzyme at rates that were significantly faster than the spontaneous rate of reduction, indicating that AA and other monomethoxylated aromatics are directly oxidized by LiP, albeit slowly. Under steady-state conditions in the presence of excess H2O2 and VA, a visible spectrum for LiPII was obtained. In contrast, under steady-state conditions in the presence of AA a visible spectrum was obtained for LiPIII*, a noncovalent complex of LiPIII and H2O2. AA competitively inhibited the oxidation of VA by LiP; the Ki for AA inhibition was 32 microM. Addition of VA to LiPIII* resulted in its conversion to the native enzyme. In contrast, AA did not convert LiPIII* to the native enzyme; instead, LiPIII* was bleached in the presence of AA. Thus, AA does not protect LiP from inactivation by H2O2.(ABSTRACT TRUNCATED AT 250 WORDS)
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0006-2960
pubmed:author
pubmed:issnType
Print
pubmed:day
18
pubmed:volume
29
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
8535-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Oxidation of monomethoxylated aromatic compounds by lignin peroxidase: role of veratryl alcohol in lignin biodegradation.
pubmed:affiliation
Department of Chemical and Biological Sciences, Oregon Graduate Institute of Science and Technology, Beaverton 97006-1999.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S.