Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1999-6-7
pubmed:abstractText
The tRNALys-specific anticodon nuclease exists in latent form in Escherichia coli strains containing the optional prr locus. The latency is a result of a masking interaction between the anticodon nuclease core-polypeptide PrrC and the Type IC DNA restriction-modification enzyme EcoprrI. Activation of the latent enzyme by phage T4-infection elicits cleavage of tRNALys 5' to the wobble base, yielding 5'-OH and 2', 3'-cyclic phosphate termini. The N-proximal half of PrrC has been implicated with (A/G) TPase and EcoprrI interfacing activities. Therefore, residues involved in recognition and cleavage of tRNALys were searched for at the C-half. Random mutagenesis of the low-G+C portion encoding PrrC residues 200-313 was performed, followed by selection for loss of anticodon nuclease-dependent lethality and production of full-sized PrrC-like protein. This process yielded a cluster of missense mutations mapping to a region highly conserved between PrrC and two putative Neisseria meningitidis MC58 homologues. This cluster included two adjacent members that relaxed the inherent enzyme's cleavage specificity. We also describe another mode of relaxed specificity, due to mere overexpression of PrrC. This mode was shared by wild-type PrrC and the other mutant alleles. The additional substrates recognised under the promiscuous conditions had, in general, anticodons resembling that of tRNALys. Taken together, the data suggest that the anticodon of tRNALys harbours anticodon nuclease identity elements and implicates a conserved region in PrrC in their recognition.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Apr
pubmed:issn
0022-2836
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Academic Press.
pubmed:issnType
Print
pubmed:day
2
pubmed:volume
287
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
499-510
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10092455-Amino Acid Sequence, pubmed-meshheading:10092455-Bacterial Proteins, pubmed-meshheading:10092455-Base Sequence, pubmed-meshheading:10092455-Binding Sites, pubmed-meshheading:10092455-Conserved Sequence, pubmed-meshheading:10092455-DNA Primers, pubmed-meshheading:10092455-Enzyme Activation, pubmed-meshheading:10092455-Escherichia coli, pubmed-meshheading:10092455-Escherichia coli Proteins, pubmed-meshheading:10092455-Gene Expression, pubmed-meshheading:10092455-Genes, Bacterial, pubmed-meshheading:10092455-Molecular Sequence Data, pubmed-meshheading:10092455-Mutation, Missense, pubmed-meshheading:10092455-Phenotype, pubmed-meshheading:10092455-RNA, Transfer, Lys, pubmed-meshheading:10092455-Ribonucleases, pubmed-meshheading:10092455-Sequence Homology, Amino Acid, pubmed-meshheading:10092455-Substrate Specificity
pubmed:year
1999
pubmed:articleTitle
Detection of anticodon nuclease residues involved in tRNALys cleavage specificity.
pubmed:affiliation
Department of Biochemistry, Tel Aviv University, Ramat Aviv, 69978, Israel.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't