Linked Life Data

6852529

Source:http://linkedlifedata.com/resource/pubmed/id/6852529

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
1983-7-8
pubmed:abstractText
Hybrid plasmid molecules carrying an insert of pneumococcal DNA can integrate into the pneumococcal genome by homologous recombination. The resulting structure is a duplication of the pneumococcal DNA insert bracketing a vector genome. To select for plasmid integration, the vector plasmid was marked with an erythromycin (ery) resistance determinant (eryr) originating from pVA736, a streptococcal plasmid. Experiments with pR27 and pR28, two plasmids carrying the same insert of pneumococcal DNA but in opposite orientations, led to the following observation: (i) In one orientation of the ery region with respect to the amiA locus, cells exhibited a low-level resistance to ery; when these cells were grown in the presence of ery, amplification of the integrated plasmid occurred and cells became resistant to a high level of antibiotic. (ii) In the opposite orientation, a high level of resistance was observed, without need for amplification. These results indicate that, in the orientation conferring a high-level resistance without amplification, the ery region is transcribed both from its own promoter and from the promoter of the amiA locus. In the opposite orientation, a low level of transcription from the eryr promoter could account for a strong selective pressure for the amplified state, which then allows for rapid growth in the presence of ery.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0378-1119
pubmed:author
pubmed:issnType
Print
pubmed:volume
21
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
285-92
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1983
pubmed:articleTitle
Amplification of a chimeric plasmid carrying an erythromycin-resistance determinant introduced into the genome of Streptococcus pneumoniae.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't