Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1976-3-1
pubmed:abstractText
The activities of polymyxin B sulphate, colistin (polymyxin E) sulphate and their sulphomethyl derivatives were compared by continuous turbidimetric monitoring of dense cultures of an Escherichia coli strain exposed to these agents. Judged by the concentration of antibiotic which caused a rapid fall in opacity of the culture, polymyxin B sulphate and colistin sulphate had similar activities, but the sulphomethyl compounds differed considerably: sulphomyxin sodium induced lysis of the culture at a concentration four times that of the parent compound, whereas colistin sulphomethate sodium induced a delayed fall in opacity consistent with recruitment of activity as the inactive sulphomethyl derivative was broken down to the parent compound. Durign overnight incubation, regrowth of cultures which had initially succumbed to polymyxin action occurred, apparently due to the selection of phenotypically resistant variants from within the population. In this way cultures could easily be adapted to growth in concentrations of antibiotic well above the conventionally-determined minimum inhibitory concentration. The comparative ease of adaptation was in the order: colistin sulphomethate greater than sulphomyxin greater than colistin sulphate greater than polymyxin B sulphate.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Nov
pubmed:issn
0022-1287
pubmed:author
pubmed:issnType
Print
pubmed:volume
91
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
110-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1975
pubmed:articleTitle
The activity of polymyxins against dense populations of Escherichia coli.
pubmed:publicationType
Journal Article, Comparative Study