Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
42
pubmed:dateCreated
1994-11-22
pubmed:abstractText
The anaerobic Escherichia coli ribonucleotide reductase (class III reductase) responsible for the synthesis of the deoxyribonucleotides required for anaerobic DNA replication contains an oxygen-sensitive glycyl radical (Gly-681) suggesting involvement of radical chemistry in catalysis. The amino acid sequence of this enzyme completely differs from that of earlier described aerobic class I (prototype, aerobic E. coli) and class II (prototype, Lactobacillus leichmanii) reductases that use radical chemistry but employ other means for radical generation. Here, we study the interaction between the anaerobic E. coli reductase with the 5'-triphosphates of 2'-chloro-2'-deoxycytidine, 2'-fluoro-2'-deoxycytidine, and 2'-azido-2'-deoxycytidine (N3CTP), which are mechanism-based inhibitors of class I and II reductases and, on interaction with these enzymes, decompose to base, inorganic di(tri)phosphate and 2'-methylene-3(2H)-furanone. Also, with the anaerobic E. coli reductase, the 2'-substituted nucleotides act as mechanism-based inhibitors and decompose. N3CTP scavenges the glycyl radical of the enzyme similar to the interaction of N3CDP with the tyrosyl radical of class I enzymes. However, we found no evidence for a new transient radical species as is the case with class I enzymes. Our results suggest that the chemistry at the nucleotide level for the reduction of ribose by class III enzymes is similar to the chemistry employed by class I and II enzymes.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Oct
pubmed:issn
0021-9258
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
269
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
26116-20
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1994
pubmed:articleTitle
Interactions of 2'-modified azido- and haloanalogs of deoxycytidine 5'-triphosphate with the anaerobic ribonucleotide reductase of Escherichia coli.
pubmed:affiliation
Department of Biochemistry 1, MBB, Medical Nobel Institute, Karolinska Institutet, Stockholm, Sweden.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't