Linked Life Data

11784318

Source:http://linkedlifedata.com/resource/pubmed/id/11784318

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2002-1-10
pubmed:abstractText
Chlorophyll biosynthesis requires a metabolic dialog between the chloroplast envelope and thylakoids where biosynthetic activities are localized. Here, we report the first plant S-adenosyl-l-methionine:Mg-protoporphyrin IX methyltransferase (MgP(IX)MT) sequence identified in the Arabidopsis genome owing to its similarity with the Synechocystis sp. MgP(IX)MT gene. After expression in Escherichia coli, the recombinant Arabidopsis thaliana cDNA was shown to encode a protein having MgP(IX)MT activity. The full-length polypeptide exhibits a chloroplast transit peptide that is processed during import into the chloroplast. The mature protein contains two functional regions. The C-terminal part aligns with the Synechocystis full-length protein. The corresponding truncated region binds to Ado-met, as assayed by UV crosslinking, and is shown to harbor the MgP(IX)MT activity. Downstream of the cleaved transit peptide, the 40 N-terminal amino acids of the mature protein are very hydrophobic and enhance the association of the protein with the membrane. In A. thaliana and spinach, the MgP(IX)MT protein has a dual localization in chloroplast envelope membranes as well as in thylakoids. The protein is active in each membrane and has the same apparent size corresponding to the processed mature protein. The protein is very likely a monotopic membrane protein embedded within one leaflet of the membrane as indicated by ionic and alkaline extraction of each membrane. The rationale for a dual localization of the protein in the chloroplast is discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
0014-2956
pubmed:author
pubmed:issnType
Print
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
240-8
pubmed:dateRevised
2007-7-23
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
The plant S-adenosyl-L-methionine:Mg-protoporphyrin IX methyltransferase is located in both envelope and thylakoid chloroplast membranes.
pubmed:affiliation
Laboratoire de Physiologie Cellulaire Végétale, CNRS/CEA/Université Joseph Fourier, DBMS/PCV, Grenoble, France. mblock@cea.fr
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't