Linked Life Data

11152068

Source:http://linkedlifedata.com/resource/pubmed/id/11152068

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6
pubmed:dateCreated
2001-1-9
pubmed:abstractText
A gene encoding the sweet-tasting protein thaumatin (tha) with optimized codon usage was expressed in Aspergillus awamori. Mutants of A. awamori with reduced proteolytic activity were isolated. One of these mutants, named lpr66, contained an insertion of about 200 bp in the pepA gene, resulting in an inactive aspergillopepsin A. In vitro thaumatin degradation tests confirmed that culture broths of mutant lpr66 showed only a small thaumatin-degrading activity. A. awamori lpr66 has been used as host strain for thaumatin expression cassettes containing the tha gene under the control of either the cahB (cephalosporin acetylhydrolase) promoter of Acremonium chrysogenum or the gdhA (glutamate dehydrogenase) promoter of Aspergillus awamori. Residual proteolytic activities were repressed by using a mixture of glucose and sucrose as carbon sources and L-asparagine as nitrogen source. Degradation of thaumatin by acidic proteases was prevented by maintaining the pH value at 6.2 in the fermentor. Expression of cassettes containing the gdhA promoter was optimal in ammonium sulfate as nitrogen source, whereas transformants expressing the tha gene from the cahB promoter yielded higher thaumatin levels using L-asparagine as nitrogen source. Under optimal fermentation conditions, yields of 105 mg thaumatin/l were obtained, thus making this fermentation a process of industrial interest.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Dec
pubmed:issn
0175-7598
pubmed:author
pubmed:issnType
Print
pubmed:volume
54
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
772-7
pubmed:dateRevised
2009-11-19
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Overexpression and lack of degradation of thaumatin in an aspergillopepsin A-defective mutant of Aspergillus awamori containing an insertion in the pepA gene.
pubmed:affiliation
Institute of Biotechnology INBIOTEC, Science Park of León, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't