Biomaterial Database

Nutritional regulation of yeast delta-9 fatty acid desaturase activity. 1989

M A Bossie, and C E Martin

Bureau of Biological Research, Nelson Laboratories, Rutgers University, Piscataway, New Jersey 08855-1059.

The addition of unsaturated fatty acids to cultures of Saccharomyces cerevisiae significantly altered the microsomal lipid composition. Supplementation with either of the naturally occurring palmitoleic (16:1) or oleic (18:1) acids caused increased levels in membrane phospholipids and reduced levels of the complementary acid. Growth in the presence of equimolar quantities of 16:1 and 18:1 acids, however, produced a fatty acid composition similar to that found in unsupplemented cell membranes. Linoleic acid (18:2) was not found in S. cerevisiae grown under normal conditions. It was preferentially internalized and incorporated into microsomes, however, at levels exceeding 50% of the total fatty acid species. This resulted in an almost total loss of 16:1 and a reduction of 18:1 to 25% of its normal level. The delta-9 fatty acid desaturase, a microsomal enzyme that forms 16:1 and 18:1 from saturated acyl coenzyme A precursors, was affected by the presence of exogenous fatty acids. Enzyme activity toward the 16:0 coenzyme A substrate was elevated in microsomes from saturated-fatty-acid-supplemented cultures and sharply repressed following the addition of unsaturated fatty acids, including 18:2. Northern (RNA blot) and slot-blot analyses of mRNA encoded by the OLE1 gene, which appears to be the structural gene for the delta-9 desaturase, indicated that it was sharply reduced in unsaturated-fatty-acid-fed cells. These data suggest that a significant part of the regulation involves modulation of available transcripts.

UI	MeSH Term	Description	Entries
D008861	Microsomes	Artifactual vesicles formed from the endoplasmic reticulum when cells are disrupted. They are isolated by differential centrifugation and are composed of three structural features: rough vesicles, smooth vesicles, and ribosomes. Numerous enzyme activities are associated with the microsomal fraction. (Glick, Glossary of Biochemistry and Molecular Biology, 1990; from Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)	Microsome
D005231	Fatty Acids, Unsaturated	FATTY ACIDS in which the carbon chain contains one or more double or triple carbon-carbon bonds.	Fatty Acids, Polyunsaturated,Polyunsaturated Fatty Acid,Unsaturated Fatty Acid,Polyunsaturated Fatty Acids,Acid, Polyunsaturated Fatty,Acid, Unsaturated Fatty,Acids, Polyunsaturated Fatty,Acids, Unsaturated Fatty,Fatty Acid, Polyunsaturated,Fatty Acid, Unsaturated,Unsaturated Fatty Acids
D005800	Genes, Fungal	The functional hereditary units of FUNGI.	Fungal Genes,Fungal Gene,Gene, Fungal
D012331	RNA, Fungal	Ribonucleic acid in fungi having regulatory and catalytic roles as well as involvement in protein synthesis.	Fungal RNA
D012333	RNA, Messenger	RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm.	Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D012441	Saccharomyces cerevisiae	A species of the genus SACCHAROMYCES, family Saccharomycetaceae, order Saccharomycetales, known as "baker's" or "brewer's" yeast. The dried form is used as a dietary supplement.	Baker's Yeast,Brewer's Yeast,Candida robusta,S. cerevisiae,Saccharomyces capensis,Saccharomyces italicus,Saccharomyces oviformis,Saccharomyces uvarum var. melibiosus,Yeast, Baker's,Yeast, Brewer's,Baker Yeast,S cerevisiae,Baker's Yeasts,Yeast, Baker
D013230	Stearoyl-CoA Desaturase	An enzyme that catalyzes the formation of oleoyl-CoA, A, and water from stearoyl-CoA, AH2, and oxygen where AH2 is an unspecified hydrogen donor.	Stearyl-CoA Desaturase,Stearate Desaturase,delta-9 Desaturase,Desaturase, Stearate,Desaturase, Stearoyl-CoA,Desaturase, Stearyl-CoA,Desaturase, delta-9,Stearoyl CoA Desaturase,Stearyl CoA Desaturase,delta 9 Desaturase
D013329	Structure-Activity Relationship	The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.	Relationship, Structure-Activity,Relationships, Structure-Activity,Structure Activity Relationship,Structure-Activity Relationships
D015152	Blotting, Northern	Detection of RNA that has been electrophoretically separated and immobilized by blotting on nitrocellulose or other type of paper or nylon membrane followed by hybridization with labeled NUCLEIC ACID PROBES.	Northern Blotting,Blot, Northern,Northern Blot,Blots, Northern,Blottings, Northern,Northern Blots,Northern Blottings
D015966	Gene Expression Regulation, Fungal	Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in fungi.	Fungal Gene Expression Regulation,Regulation of Gene Expression, Fungal,Regulation, Gene Expression, Fungal