Linked Life Data

12545382

Source:http://linkedlifedata.com/resource/pubmed/id/12545382

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2003-1-24
pubmed:abstractText
This work demonstrates the first example of a fungal lactate dehydrogenase (LDH) expressed in yeast. A L(+)-LDH gene, ldhA, from the filamentous fungus Rhizopus oryzae was modified to be expressed under control of the Saccharomyces cerevisiae adh1 promoter and terminator and then placed in a 2 micro -containing yeast-replicating plasmid. The resulting construct, pLdhA68X, was transformed and tested by fermentation analyses in haploid and diploid yeast containing similar genetic backgrounds. Both recombinant strains utilized 92 g glucose/l in approximately 30 h. The diploid isolate accumulated approximately 40% more lactic acid with a final concentration of 38 g lactic acid/l and a yield of 0.44 g lactic acid/g glucose. The optimal pH for lactic acid production by the diploid strain was pH 5. LDH activity in this strain remained relatively constant at 1.5 units/mg protein throughout the fermentation. The majority of carbon was still diverted to the ethanol fermentation pathway, as indicated by ethanol yields between 0.25-0.33 g/g glucose. S. cerevisiae mutants impaired in ethanol production were transformed with pLdhA68X in an attempt to increase the lactic acid yield by minimizing the conversion of pyruvate to ethanol. Mutants with diminished pyruvate decarboxylase activity and mutants with disrupted alcohol dehydrogenase activity did result in transformants with diminished ethanol production. However, the efficiency of lactic acid production also decreased.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jan
pubmed:issn
1367-5435
pubmed:author
pubmed:issnType
Print
pubmed:volume
30
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
22-7
pubmed:dateRevised
2003-11-14
pubmed:meshHeading
pubmed:year
2003
pubmed:articleTitle
Lactic acid production by Saccharomyces cerevisiae expressing a Rhizopus oryzae lactate dehydrogenase gene.
pubmed:affiliation
Fermentation Biotechnology Research Unit, National Center for Agricultural Utilization Research, USDA Agricultural Research Service, 1815 N. University Street, Peoria IL 61604, USA. skorycd@ncaur.usda.gov
pubmed:publicationType
Journal Article