Multiplatform Mass Spectrometry-Based Approach Identifies Extracellular Glycolipids of the Yeast Rhodotorula babjevae UCDFST 04-877.
A multiplatform mass spectrometry-based approach was used for elucidating extracellular lipids with biosurfactant properties produced by the oleaginous yeast Rhodotorula babjevae UCDFST 04-877. This strain secreted 8.6 ± 0.1 g/L extracellular lipids when grown in a benchtop bioreactor fed with 100 g/L glucose in medium without addition of hydrophobic substrate, such as oleic acid. Untargeted reversed-phase liquid chromatography-quadrupole/time-of-flight mass spectrometry (QTOFMS) detected native glycolipid molecules with masses of 574-716 Da. After hydrolysis into the fatty acid and sugar components and hydrophilic interaction chromatography-QTOFMS analysis, the extracellular lipids were found to consist of hydroxy fatty acids and sugar alcohols. Derivatization and chiral separation gas chromatography-mass spectrometry (GC-MS) identified these components as d-arabitol, d-mannitol, (R)-3-hydroxymyristate, (R)-3-hydroxypalmitate, and (R)-3-hydroxystearate. In order to assemble these substructures back into intact glycolipids that were detected in the initial screen, potential structures were in-silico acetylated to match the observed molar masses and subsequently characterized by matching predicted and observed MS/MS fragmentation using the Mass Frontier software program. Eleven species of acetylated sugar alcohol esters of hydroxy fatty acids were characterized for this yeast strain.
UC Davis Genome Center-Metabolomics, University of California, Davis , 451 Health Sciences Drive, Davis, California 95616, United States.
Tomas
T
Cajka
Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California Davis , One Shields Avenue, Davis, California 95616, United States.
Luis A
LA
Garay
Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California Davis , One Shields Avenue, Davis, California 95616, United States.|Bioentrepreneurship Department, Indonesia International Institute for Life Sciences , Jalan Pulo Mas Barat Kav. 88, East Jakarta, DKI Jakarta 13210, Indonesia.
Irnayuli R
IR
Sitepu
Phaff Yeast Culture Collection, Department of Food Science and Technology, University of California Davis , One Shields Avenue, Davis, California 95616, United States.
Kyria L
KL
Boundy-Mills
UC Davis Genome Center-Metabolomics, University of California, Davis , 451 Health Sciences Drive, Davis, California 95616, United States.|Biochemistry Department, Faculty of Science, King Abdulaziz University , P.O. Box 80203, Jeddah 21589, Saudi Arabia.
Oliver
O
Fiehn
D008401:Gas Chromatography-Mass Spectrometry; D006017:Glycolipids / Q000737:chemistry* / Q000302:isolation & purification*; D008055:Lipids / Q000737:chemistry*; D015394:Molecular Structure; D012248:Rhodotorula / Q000737:chemistry*; D013402:Sugar Alcohols / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*
D006017:Glycolipids; D008055:Lipids; D013402:Sugar Alcohols; C014999:arabitol