Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177
The pH influence on continuous citric acid secretion was investigated in Candida oleophila ATCC 20177 (var.) under NH4+ limiting state steady conditions, using glucose. Highest citric acid concentration of 57.8 g/l, citrate/isocitrate ratio of 15.6, space-time yield of 0.96 g/(l x hr) and biomass sp...
Guardado en:
| Autores principales: | , |
|---|---|
| Lenguaje: | English |
| Publicado: |
Pontificia Universidad Católica de Valparaíso
2005
|
| Materias: | |
| Acceso en línea: | http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200004 |
| Etiquetas: |
Agregar Etiqueta
Sin Etiquetas, Sea el primero en etiquetar este registro!
|
| id |
oai:scielo:S0717-34582005000200004 |
|---|---|
| record_format |
dspace |
| spelling |
oai:scielo:S0717-345820050002000042005-10-13Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177Anastassiadis,SavasRehm,Hans-Jürgen active citrate export citric acid fermentation energy consuming citric acid secretion specific active transport system The pH influence on continuous citric acid secretion was investigated in Candida oleophila ATCC 20177 (var.) under NH4+ limiting state steady conditions, using glucose. Highest citric acid concentration of 57.8 g/l, citrate/isocitrate ratio of 15.6, space-time yield of 0.96 g/(l x hr) and biomass specific productivity of 0.041 g/(g x hr) were obtained at pH 5 and 60 hrs residence time. Only 22.8 g/l (39.4%) and a ratio of 9.9 were achieved at pH 6 pH and 12.4 g/l (21.5%) and a ratio of 3.7 at pH 3. Under non producing conditions, in excess of nitrogen, biomass concentration increased at raising pH. An iron concentration of 200 ppm was determined in biomass of C. oleophila at pH 5, compared with only 26 ppm found at pH 3 (factor 7.7). Intra- and extracellular concentrations of citrates and glucose confirmed the existence of a high specific, pH dependent active transport system for citrate secretion, while isocitrate isnt a high-affine substrate, displaying a strong correlation with ATP/ADP ratio. Differences between extra- and intracellular concentration of citrate higher than 1 and up to about 60 were determined. The active transport systemfor citrate excretion appears to be the main speed-determining factor in citrate overproduction by yeastsinfo:eu-repo/semantics/openAccessPontificia Universidad Católica de ValparaísoElectronic Journal of Biotechnology v.8 n.2 20052005-08-01text/htmlhttp://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200004en |
| institution |
Scielo Chile |
| collection |
Scielo Chile |
| language |
English |
| topic |
active citrate export citric acid fermentation energy consuming citric acid secretion specific active transport system |
| spellingShingle |
active citrate export citric acid fermentation energy consuming citric acid secretion specific active transport system Anastassiadis,Savas Rehm,Hans-Jürgen Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| description |
The pH influence on continuous citric acid secretion was investigated in Candida oleophila ATCC 20177 (var.) under NH4+ limiting state steady conditions, using glucose. Highest citric acid concentration of 57.8 g/l, citrate/isocitrate ratio of 15.6, space-time yield of 0.96 g/(l x hr) and biomass specific productivity of 0.041 g/(g x hr) were obtained at pH 5 and 60 hrs residence time. Only 22.8 g/l (39.4%) and a ratio of 9.9 were achieved at pH 6 pH and 12.4 g/l (21.5%) and a ratio of 3.7 at pH 3. Under non producing conditions, in excess of nitrogen, biomass concentration increased at raising pH. An iron concentration of 200 ppm was determined in biomass of C. oleophila at pH 5, compared with only 26 ppm found at pH 3 (factor 7.7). Intra- and extracellular concentrations of citrates and glucose confirmed the existence of a high specific, pH dependent active transport system for citrate secretion, while isocitrate isnt a high-affine substrate, displaying a strong correlation with ATP/ADP ratio. Differences between extra- and intracellular concentration of citrate higher than 1 and up to about 60 were determined. The active transport systemfor citrate excretion appears to be the main speed-determining factor in citrate overproduction by yeasts |
| author |
Anastassiadis,Savas Rehm,Hans-Jürgen |
| author_facet |
Anastassiadis,Savas Rehm,Hans-Jürgen |
| author_sort |
Anastassiadis,Savas |
| title |
Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| title_short |
Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| title_full |
Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| title_fullStr |
Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| title_full_unstemmed |
Continuous citric acid secretion by a high specific pH dependent active transport system in yeast Candida oleophila ATCC 20177 |
| title_sort |
continuous citric acid secretion by a high specific ph dependent active transport system in yeast candida oleophila atcc 20177 |
| publisher |
Pontificia Universidad Católica de Valparaíso |
| publishDate |
2005 |
| url |
http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582005000200004 |
| work_keys_str_mv |
AT anastassiadissavas continuouscitricacidsecretionbyahighspecificphdependentactivetransportsysteminyeastcandidaoleophilaatcc20177 AT rehmhansjurgen continuouscitricacidsecretionbyahighspecificphdependentactivetransportsysteminyeastcandidaoleophilaatcc20177 |
| _version_ |
1718441733020188672 |