scholarly journals Heterologous expression of peptide hormone precursors in the yeast Saccharomyces cerevisiae. Evidence for a novel prohormone endoprotease with specificity for monobasic amino acids

1991 ◽  
Vol 266 (20) ◽  
pp. 13203-13209
Author(s):  
Y. Bourbonnais ◽  
A. Danoff ◽  
D.Y. Thomas ◽  
D. Shields
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Heterologous Expression ◽  
Peptide Hormone ◽  
Yeast Saccharomyces Cerevisiae

scholarly journals SEN1, a positive effector of tRNA-splicing endonuclease in Saccharomyces cerevisiae.

1992 ◽  
Vol 12 (5) ◽  
pp. 2154-2164 ◽  
Author(s):  
D J DeMarini ◽  
M Winey ◽  
D Ursic ◽  
F Webb ◽  
M R Culbertson
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Amino Acid ◽  
Gene Product ◽  
Signal Sequence ◽  
Null Alleles ◽  
Nucleoside Triphosphate ◽  
Temperature Sensitive ◽  
Yeast Saccharomyces Cerevisiae ◽  
Amino Terminal

The SEN1 gene, which is essential for growth in the yeast Saccharomyces cerevisiae, is required for endonucleolytic cleavage of introns from all 10 families of precursor tRNAs. A mutation in SEN1 conferring temperature-sensitive lethality also causes in vivo accumulation of pre-tRNAs and a deficiency of in vitro endonuclease activity. Biochemical evidence suggests that the gene product may be one of several components of a nuclear-localized splicing complex. We have cloned the SEN1 gene and characterized the SEN1 mRNA, the SEN1 gene product, the temperature-sensitive sen1-1 mutation, and three SEN1 null alleles. The SEN1 gene corresponds to a 6,336-bp open reading frame coding for a 2,112-amino-acid protein (molecular mass, 239 kDa). Using antisera directed against the C-terminal end of SEN1, we detect a protein corresponding to the predicted molecular weight of SEN1. The SEN1 protein contains a leucine zipper motif, consensus elements for nucleoside triphosphate binding, and a potential nuclear localization signal sequence. The carboxy-terminal 1,214 amino acids of the SEN1 protein are essential for growth, whereas the amino-terminal 898 amino acids are dispensable. A sequence of approximately 500 amino acids located in the essential region of SEN1 has significant similarity to the yeast UPF1 gene product, which is involved in mRNA turnover, and the mouse Mov-10 gene product, whose function is unknown. The mutation that creates the temperature-sensitive sen1-1 allele is located within this 500-amino-acid region, and it causes a substitution for an amino acid that is conserved in all three proteins.

The immunosuppressant FK506 inhibits amino acid import in Saccharomyces cerevisiae

1993 ◽  
Vol 13 (8) ◽  
pp. 5010-5019 ◽  
Author(s):  
J Heitman ◽  
A Koller ◽  
J Kunz ◽  
R Henriquez ◽  
A Schmidt ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Amino Acid ◽  
Cyclosporin A ◽  
Secretory Pathway ◽  
Yeast Cells ◽  
Amino Acid Transporters ◽  
Yeast Saccharomyces Cerevisiae ◽  
Eukaryotic Microorganisms

The immunosuppressants cyclosporin A, FK506, and rapamycin inhibit growth of unicellular eukaryotic microorganisms and also block activation of T lymphocytes from multicellular eukaryotes. In vitro, these compounds bind and inhibit two different types of peptidyl-prolyl cis-trans isomerases. Cyclosporin A binds cyclophilins, whereas FK506 and rapamycin bind FK506-binding proteins (FKBPs). Cyclophilins and FKBPs are ubiquitous, abundant, and targeted to multiple cellular compartments, and they may fold proteins in vivo. Previously, a 12-kDa cytoplasmic FKBP was shown to be only one of at least two FK506-sensitive targets in the yeast Saccharomyces cerevisiae. We find that a second FK506-sensitive target is required for amino acid import. Amino acid-auxotrophic yeast strains (trp1 his4 leu2) are FK506 sensitive, whereas prototrophic strains (TRP1 his4 leu2, trp1 HIS4 leu2, and trp1 his4 LEU2) are FK506 resistant. Amino acids added exogenously to the growth medium mitigate FK506 toxicity. FK506 induces GCN4 expression, which is normally induced by amino acid starvation. FK506 inhibits transport of tryptophan, histidine, and leucine into yeast cells. Lastly, several genes encoding proteins involved in amino acid import or biosynthesis confer FK506 resistance. These findings demonstrate that FK506 inhibits amino acid import in yeast cells, most likely by inhibiting amino acid transporters. Amino acid transporters are integral membrane proteins which import extracellular amino acids and constitute a protein family sharing 30 to 35% identity, including eight invariant prolines. Thus, the second FK506-sensitive target in yeast cells may be a proline isomerase that plays a role in folding amino acid transporters during transit through the secretory pathway.

scholarly journals The Lipomyces starkeyi gene Ls120451 encodes a cellobiose transporter that enables cellobiose fermentation in Saccharomyces cerevisiae

2020 ◽  
Vol 20 (3) ◽  
Author(s):  
Jorg C de Ruijter ◽  
Kiyohiko Igarashi ◽  
Merja Penttilä
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Aspergillus Niger ◽  
Heterologous Expression ◽  
In Silico ◽  
Penicillium Oxalicum ◽  
Microbial Fermentation ◽  
Lipomyces Starkeyi ◽  
Yeast Saccharomyces Cerevisiae ◽  
Sugar Transporters ◽  
Selection Of

ABSTRACT Processed lignocellulosic biomass is a source of mixed sugars that can be used for microbial fermentation into fuels or higher value products, like chemicals. Previously, the yeast Saccharomyces cerevisiae was engineered to utilize its cellodextrins through the heterologous expression of sugar transporters together with an intracellular expressed β-glucosidase. In this study, we screened a selection of eight (putative) cellodextrin transporters from different yeast and fungal hosts in order to extend the catalogue of available cellobiose transporters for cellobiose fermentation in S. cerevisiae. We confirmed that several in silico predicted cellodextrin transporters from Aspergillus niger were capable of transporting cellobiose with low affinity. In addition, we found a novel cellobiose transporter from the yeast Lipomyces starkeyi, encoded by the gene Ls120451. This transporter allowed efficient growth on cellobiose, while it also grew on glucose and lactose, but not cellotriose nor cellotetraose. We characterized the transporter more in-depth together with the transporter CdtG from Penicillium oxalicum. CdtG showed to be slightly more efficient in cellobiose consumption than Ls120451 at concentrations below 1.0 g/L. Ls120451 was more efficient in cellobiose consumption at higher concentrations and strains expressing this transporter grew slightly slower, but produced up to 30% more ethanol than CdtG.

scholarly journals Effect of heterologous expression of acyl-CoA-binding protein on acyl-CoA level and composition in yeast

1993 ◽  
Vol 290 (2) ◽  
pp. 369-374 ◽  
Author(s):  
S Mandrup ◽  
R Jepsen ◽  
H Skøtt ◽  
J Rosendal ◽  
P Højrup ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Growth Rate ◽  
Heterologous Expression ◽  
Binding Protein ◽  
Cellular Protein ◽  
Serine Residue ◽  
Yeast Saccharomyces Cerevisiae ◽  
Total Cellular Protein ◽  
Gal1 Promoter

We have expressed a bovine synthetic acyl-CoA-binding protein (ACBP) gene in yeast (Saccharomyces cerevisiae) under the control of the GAL1 promoter. The heterologously expressed bovine ACBP constituted up to 6.4% of total cellular protein and the processing was identical with that of native bovine ACBP, i.e. the initiating methionine was removed and the following serine residue was N-acetylated. The expression of this protein did not affect the growth rate of the cells. Determination of the yeast acyl-CoA pool size showed a close positive correlation between the ACBP content of the cells and the size of the acyl-CoA pool. Thus ACBP can act as an intracellular acyl-CoA pool former. Possible physiological functions of ACBP in cells are discussed.

scholarly journals Properties of the DNA-binding domain of the Saccharomyces cerevisiae STE12 protein.

1991 ◽  
Vol 11 (12) ◽  
pp. 5910-5918 ◽  
Author(s):  
Y L Yuan ◽  
S Fields
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Dna Binding ◽  
Binding Affinity ◽  
Binding Domain ◽  
Upstream Region ◽  
Dna Binding Domain ◽  
Yeast Saccharomyces Cerevisiae ◽  
Dnase I Footprinting

The STE12 protein of the yeast Saccharomyces cerevisiae binds to the pheromone response element (PRE) present in the upstream region of genes whose transcription is induced by pheromone. Using DNase I footprinting assays with bacterially made STE12 fragments, we localized the DNA-binding domain to 164 amino acids near the amino terminus. Footprinting of oligonucleotide-derived sequences containing one PRE, or two PREs in head-to-tail or tail-to-tail orientation, showed that the N-terminal 215 amino acids of STE12 has similar binding affinity to either of the dimer sites and a binding affinity 5- to 10-fold lower for the monomer site. This binding cooperativity was also evident on a fragment from the MFA2 gene, which encodes the a-factor pheromone. On this fragment, the 215-amino-acid STE12 fragment protected both a consensus PRE as well as a degenerate PRE containing an additional residue. Mutation of the degenerate site led to a 5- to 10-fold decrease in binding; mutation of the consensus site led to a 25-fold decrease in binding. The ability of PREs to function as pheromone-inducible upstream activation sequences in yeast correlated with their ability to bind the STE12 domain in vitro. The sequence of the STE12 DNA-binding domain contains similarities to the homeodomain, although it is highly diverged from other known examples of this motif. Moreover, the alignment between STE12 and the homeodomain postulates loops after both the putative helix 1 and helix 2 of the STE12 sequence.

The Gcn2–eIF2α pathway connects iron and amino acid homeostasis in Saccharomyces cerevisiae

2018 ◽  
Vol 475 (8) ◽  
pp. 1523-1534 ◽  
Author(s):  
Marcos Caballero-Molada ◽  
María D. Planes ◽  
Helena Benlloch ◽  
Sergio Atares ◽  
Miguel A. Naranjo ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Amino Acid ◽  
Iron Content ◽  
Amino Acid Biosynthesis ◽  
Initiation Factor ◽  
Acid Biosynthesis ◽  
Yeast Saccharomyces Cerevisiae ◽  
Iron Sulfur ◽  
Amino Acid Homeostasis

In eukaryotic cells, amino acid biosynthesis is feedback-inhibited by amino acids through inhibition of the conserved protein kinase Gcn2. This decreases phosphorylation of initiation factor eIF2α, resulting in general activation of translation but inhibition of translation of mRNA for transcription factor (TF) Gcn4 in yeast or ATF4 in mammals. These TFs are positive regulators of amino acid biosynthetic genes. As several enzymes of amino acid biosynthesis contain iron–sulfur clusters (ISCs) and iron excess is toxic, iron and amino acid homeostasis should be co-ordinated. Working with the yeast Saccharomyces cerevisiae, we found that amino acid supplementation down-regulates expression of genes for iron uptake and decreases intracellular iron content. This cross-regulation requires Aft1, the major TF activated by iron scarcity, as well as Gcn2 and phosphorylatable eIF2α but not Gcn4. A mutant with constitutive activity of Gcn2 (GCN2c) shows less repression of iron transport genes by amino acids and increased nuclear localization of Aft1 in an iron-poor medium, and increases iron content in this medium. As Aft1 is activated by depletion of mitochondrial ISCs, it is plausible that the Gcn2–eIF2α pathway inhibits the formation of these complexes. Accordingly, the GCN2c mutant has strongly reduced activity of succinate dehydrogenase, an iron–sulfur mitochondrial enzyme, and is unable to grow in media with very low iron or with galactose instead of glucose, conditions where formation of ISCs is specially needed. This mechanism adjusts the uptake of iron to the needs of amino acid biosynthesis and expands the list of Gcn4-independent activities of the Gcn2–eIF2α regulatory system.

scholarly journals Influence of the parameters processes of cultivation of yeast Saccharomyces cerevisiae in simple periodic culture on the yield and biosynthesis of some cellular components

2018 ◽  
Vol 80 (2) ◽  
pp. 175-181 ◽  
Author(s):  
T. V. Meledina ◽  
V. A. Ivanova ◽  
H. Razan ◽  
O. V. Golovinskaya ◽  
I. V. Novikova ◽  
...  
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Amino Acids ◽  
Nutrient Medium ◽  
Initial Density ◽  
Nutrient Deficiencies ◽  
Nutrient Media ◽  
Yeast Saccharomyces Cerevisiae ◽  
Individual Factor ◽  
Cellular Components ◽  
The Impact

The growth and multiplication of the industrially significant yeast Saccharomyces cerevisiae is primarily determined by the balance of the composition of the nutrient medium used. In order to prevent a decrease in the speed of the biotechnology process and to achieve the optimal yield of the desired biosynthesis product (biomass), it is necessary to introduce such nutrient deficiencies as vitamins and trace elements into the nutrient medium. At present, there is much information about the influence of different environmental factors on the growth and multiplication of microorganisms. However, the potential possibilities of microbial cultures have not been fully used. Researchers during the preparation of nutrient media until recent time mainly use the methods of establishing one-factor dependence that are based on the principle of alternating change of each nutrient media factor with the others being constant. In this work, the impact on the biomass yield of various process parameters in their interactions is investigated. A multifactor dependence is established using the methods of mathematical design of an experiment. These methods allow both to study the effects of a large number of factors and to construct a mathematical model of the process revealing the quantitative value of each individual factor and to take into account the interfactor interactions in the system .The cultivation of the yeast Saccharomyces cerevisiae was conducted in a simple periodic culture. The factors used were: the amount of inoculum, the content of nitrogen, phosphorus and biotin in the medium. Using experimental data and multifactor analysis, it was found that under these conditions, the content of biotin in the medium mostly affects the biomass synthesis. It was established that, in an optimally composed media, the economic coefficient was independent of the size of the seeding. Moreover, it was shown that the size of the fund of free amino acids is inversely related to the consumption of the seeding: with an increase in the initial density of the population, the number of amino acids in cells decreases.

Sign in / Sign up

Export Citation Format

Share Document