Linked Life Data

11248687

Source:http://linkedlifedata.com/resource/pubmed/id/11248687

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2001-3-15
pubmed:databankReference
pubmed:abstractText
Here we report the cDNA-deduced amino-acid sequence of L-amino-acid oxidase (LAAO) from the Malayan pit viper Calloselasma rhodostoma, which shows 83% identity to LAAOs from the Eastern and Western diamondback rattlesnake (Crotalus adamanteus and Crotalus atrox, respectively). Phylogenetic comparison of the FAD-dependent ophidian LAAOs to FAD-dependent oxidases such as monoamine oxidases, D-amino-acid oxidases and tryptophan 2-monooxygenases reveals only distant relationships. Nevertheless, all LAAOs share a highly conserved dinucleotide-binding fold with monoamine oxidases, tryptophan 2-monooxygenases and various other proteins that also may have a requirement for FAD. In order to characterize Ca. rhodostoma LAAO biochemically, the enzyme was purified from snake venom to apparent homogeneity. It was found that the enzyme undergoes inactivation by either freezing or increasing the pH to above neutrality. Both inactivation processes are fully reversible and are associated with changes in the UV/visible range of the flavin absorbance spectrum. In addition, the spectral characteristics of the freeze-and pH-induced inactivated enzyme are the same, indicating that the flavin environments are similar in the two inactive conformational forms. Monovalent anions, such as Cl(-), prevent pH-induced inactivation. LAAO exhibits typical flavoprotein oxidase properties, such as thermodynamic stabilization of the red flavin semiquinone radical and formation of a sulfite adduct. The latter complex as well as the complex with the competitive substrate inhibitor, anthranilate, were only formed with the active form of the enzyme indicating diminished accessibility of the flavin binding site in the inactive form(s) of the enzyme.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:volume
268
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1679-86
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
L-amino-acid oxidase from the Malayan pit viper Calloselasma rhodostoma. Comparative sequence analysis and characterization of active and inactive forms of the enzyme.
pubmed:affiliation
Institut für Pflanzenwissenschaften, Eidgenössische Technische Hochschule Zürich, Switzerland. peter.macheroux@ipw.biol.ethz.ch
pubmed:publicationType
Journal Article