Linked Life Data

1366800

Source:http://linkedlifedata.com/resource/pubmed/id/1366800

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1991-3-8
pubmed:abstractText
A defined medium containing glucose and ammonium as the sole carbon and nitrogen sources was developed to support growth and streptonigrin production. In this defined medium, increased initial levels of ammonium resulted in increased growth suggesting that nitrogen is the growth limiting nutrient. In some cases, increased initial ammonium levels resulted in decreased specific streptonigrin productivity, suggesting that nitrogen regulatory mechanisms may adversely affect streptonigrin biosynthesis. This suggestion that nitrogen regulation adversely affects antibiotic biosynthesis is further supported by results from two studies in which the ammonium supply to the cells was controlled. In the first study, streptonigrin productivity and final titer were enhanced by the addition of an ammonium trapping agent. In the second experiment, when ammonium chloride was fed slowly throughout the course of cultivation, the production phase was lengthened and the maximum antibiotic concentration was enhanced compared to the batch controls containing either the same initial or the same total ammonium chloride levels. Although our results indicate streptonigrin production may be subject to nitrogen regulatory mechanisms, the effect of nitrogen on streptonigrin production cannot be strictly correlated to the extracellular ammonium concentration. In fact, we observed that when ammonium was depleted from the medium, streptonigrin production ceased.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
B
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0169-4146
pubmed:author
pubmed:issnType
Print
pubmed:volume
6
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
43-8
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1990
pubmed:articleTitle
Ammonium effects on streptonigrin biosynthesis by Streptomyces flocculus.
pubmed:affiliation
Department of Chemical and Biochemical Engineering, University of Maryland, Baltimore.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't