Questions tagged [yeast]

Yeasts are a polyphyletic group of unicellular fungi. Usually the term yeast is used synonymously with baker's yeast - Saccharomyces cerevisiae.

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14
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2answers
363 views

What is the tRNA gene copy variation between different yeast strains?

I just started working on predicting steady-state protein levels from different codon usage bias measures. I have whole-genome sequences (it's NGS data) from different strains of S. cerevisiae and S. ...
11
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2answers
17k views

Why is PEG important for efficient yeast transformation?

One way to do an yeast transformation is by using lithium acetate, a single-stranded carrier DNA, and PEG (1). I was wondering why is the polyethylene glycol important for the efficient transformation....
9
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1answer
2k views

How does yeast dissolve in sugar?

There's this fascinating "kitchen experiment". Take a "brick" of baker's yeast (not dry yeast), and a couple teaspoons of sugar, put them together in a cup and stir together. There's no doubt both are ...
8
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2answers
2k views

What is causing my problem with very low yields when isolating a 42kb yeast plasmid?

I have to isolate a large plasmid from yeast and transform it in E. coli. After transformation, I often get no colonies. One reason for that is the yeast mini prep hasn't worked or the DNA ...
7
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1answer
849 views

Evolution home experiment?

If I were to take bakers yeast and put it in medium of minimal sugar(whatever quantity that would be) and rice(for a source of starch), could the yeast have a "evolutionary leap" and adapt to use the ...
6
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4answers
16k views

Why do yeast ferment Equal sweetener

I had my students conduct a fermentation experiment manipulating sugar amounts (number of sugar packets in solution) and measuring CO₂ production via capture in a balloon and measuring circumference (...
6
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1answer
111 views

Proteins that are strongly overproduced in E. coli and S. cerevisiae?

I'm looking for some pointers to proteins that produce at really gigantic levels in E. coli and yeast (S. cerevisiae). Can anyone point to some champion proteins? Even in inclusion bodies and non ...
6
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1answer
744 views

Auxotrophic complementation test with yeast

If auxotrophic strains grow on minimal media do they complement each other or not? Also, is complementation the same thing as complementing each other?
5
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1answer
449 views

Is hydrochloric acid suitable for pickling food?

I was wondering whether it is possible to pickle food using hydrochloric acid (HCl), rather than acetic acid. I am not very familiar with the biology of the fermentation process involved in pickling ...
5
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2answers
1k views

What does the 34/70 in Saccharomyces pastorianus Weihenstephan 34/70 stand for?

I've searched everywhere. No Wikipedia page. No information on NCBI. I searched all occurrences of 34/70 in some primary research articles! The best I've found is this brewery forum where someone ...
5
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1answer
815 views

Meaning of “f.a.” in the species name

What does "f.a." stand for in the name of the "Wickerhamomyces menglaensis f.a." yeast species mentioned in this article https://ijs.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0....
5
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1answer
81 views

Generalism - specialism index in microbial ecology

I am doing research in Lipid metabolism in different yeast species and I would like to look into ecology of them. I would like to classify them to a Generalist/specialist based on different ...
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2answers
1k views

Do Yeast Insertion constructs revert?

If I insert a new gene with a yeast integrating plasmid and select with a drop out culture once, can I assume that the newly integrated gene will stay in the strain without putting selective pressure ...
4
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2answers
638 views

Earliest to use media after autoclaving?

I am autoclaving media to use later to inoculate yeast. How much time do I have to wait before using the media and adding the culture? Can I use it a few hours after autoclaving?
4
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3answers
938 views

Sources for common laboratory Saccharomyces strains?

I'm used to working with bacteria - some of the more common laboratory strains sometimes come with an order from some vendors. What's the most convenient source to order common straings of ...
4
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2answers
937 views

Can yeast survive without mitochondria?

Some yeast cells have very low mitochondria copy number (see number of mitochondria in non budding cell, you can count mtDNA). This makes them susceptible to fluctuations, and one can conceive that ...
4
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1answer
729 views

The effects of auto-brewery syndrome

Why are some people affected so differently by auto-brewery syndrome differently if the syndrome seems to be caused by the single organism saccharomyces cerevisiae? It is known that the syndrome has ...
4
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1answer
139 views

Online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology

Where can I find an online toolkit that provides functional similarity scores (in the form of a matrix) between two functional gene sets in the context of gene ontology? I have tried the following: ...
4
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1answer
62 views

What are the effect of microtubule or microfilament inhibition on yeast expression profile?

I was wondering whether anyone has looked at what are the expression changes in yeast when the microtubule or the microfilament polymerization is inhibited? Have there been whole-genome studies?
3
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1answer
811 views

What is the best current understanding of how yeast transformation works?

I would like to get myself up to speed with what is currently known to science about yeast transformation. Specifically, transformation of plasmids and linear DNA fragments. I am particularly ...
3
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1answer
10k views

Relationship between turgor pressure and osmotic pressure?

I would like to know if there is a relationship between osmotic pressure (inside and outside of a cell) and turgor pressure. If so, is there a way to formalize it mathematically? Thank you in advance,...
3
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1answer
331 views

Can yeast in a primary fermentation of wine be used as a source of yeast for new fermentation?

So if I were to pitch bread yeast, and get to primary fermentation, which as I understand it, is the point at which regular cellular respiration can no longer continue due to a lack of oxygen , which ...
3
votes
1answer
3k views

Does yeast grow on LB agar plates?

I would like to grow E coli cells on cellophane on top of LB plate, and then grow yeast cells on the same LB plate. Does (or how well) yeast grow on LB plates? Is there a composition media that can be ...
3
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1answer
166 views

Why did the yeast rise?

Here are the notes I made for an experiment I was doing (I didn't put it here as it is too long) (please ignore the numbers at the end of the pdf file) The graph looks like this: As you see on the ...
2
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2answers
449 views

How does DNA damage cause ageing in yeast?

As I understand it, in yeast ageing there is daughter cell and mother cell. The daughter cell is has newly "fresh" DNA and mother cell dies after some counts of replication. What happens to the ...
2
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3answers
3k views

Why would yeast grow but not produce alcohol?

I'm studying for my intro to microbiology test and I have a question asking why a culture of yeast responsible for producing alcohol would be growing, but not producing alcohol? The multiple choice ...
2
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2answers
117 views

Downloading specific yeast genes in an automated manner?

I have 6 genes of Candida albicans yeast namely orf19.723, orf19.5908, orf19.610, ...
2
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1answer
47 views

Rice left in water for several months - what biological reactions or growths would occur?

In an attempt to make a hair care product, uncooked white basmati rice was left in an air-tight container half filled with tap water for several months. When opening the container, the smell was ...
2
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1answer
240 views

Is the CMV promoter active in yeast?

I wish to transfect yeast and want to control my efficiency. So I thought to use pEGFP-N1 as control. The EGFP is driven by a CMV promoter. Can yeast read CMV promoters. Thanks Hermann
2
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2answers
96 views

identifying which SNPs sit in TFBS (Yeast)

i have a set of ~11k SNPs for Saccharomyces cerevisiae, baker's yeast and i would like to identify which ones of these sit in transcription factor binding sites and if they do information on the ...
2
votes
1answer
174 views

Why does the stability of YAC increase with size?

From Lehninger Principles of Biochemistry : The stability of YAC increases with size (up to a limit). Those with inserts of less than 100000 are gradually lost during mitosis. Why does this ...
2
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1answer
35 views

Pichia pastoris and ornithine

Can Pichia pastoris (species of yeast used for recombinant protein) produce the non-protein amino acid Ornithine? Or does it express ornithine at all?
2
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1answer
1k views

Yeast absorption of different spectra of light

I'd like to monitor the growth of a yeast population by shining light through it and monitoring the change in light that gets through as it grows. I'm not sure if I should use IR, or any particular ...
2
votes
1answer
119 views

Aerobe or facultative anaerobe organism that metabolizes acetate?

I'm assuming bacteria, but will take any suggestions. Organism must survive primarily on the acetate (plus trace elements), but I can give/take electrons, if necessary. Not interested in strict ...
2
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0answers
57 views

What is the maximal insert length for PCR based homologous recombination in S. cerevisae

I would like to insert a 6 kbp construct, which I have on a plasmid into the genome of S. cerevisiae. This plasmid was originally constructed to integrate at the HIS locus via homologous recombination ...
2
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0answers
818 views

Why not use lactase to aid the break down of lactose when making biofuels?

I did an experiment using nine different substrates (Lactose + lactase, corn, sugar cane, glucose control, wood, grass, no yeast control and yeast control) and observed their fermentation rates. ...
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1answer
465 views

How can I measure the population growth of yeast?

So I will soon have to carry out an experiment. I thought about estimating the rate of growth of a populaiton of yeast, although I do not know if it is possible to at least estimate the number of ...
1
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1answer
2k views

Why does yeast react the way it does to water combined with sugar?

I almost wanted to ask this in Cooking SE, but thought it would be better fit here. So I understand than when you mix yeast with sugar and warm water, you get CO2. When using baking powder, it's a ...
1
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1answer
97 views

Enzyme Inhibitors: Using in vivo in yeast

I find listed on the Sigma-Aldrich site a large list of enzymes & corresponding inhibitors. e.g. For the enzyme squalene synthase the inhibitor listed is "Zaragozic acid A trisodium salt" Would ...
1
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1answer
326 views

Yeast Strain with squalene synthase / farnesyltransferase (ERG9) gene deleted

I was interested in obtaining a yeast strain without the enzyme farnesyltransferase (Which catalyses conversion of FPP to Squalene). The Euroscraf database has thousands of yeast strains with ...
1
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1answer
29 views

What are the best plants to cultivate yeast from?

I know that cultivating yeast from potatoes yields a good brewing yeast and that forms of wheat make good baking yeast, however; I have not seen much information on other useful plant yeast cultures. ...
1
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1answer
85 views

How to measure the length of mitochondria from z stack fluorescent microscopy image?

I have been working on yeast cells to analyse the effect of DNA damaging agents on mitochondrial structure. I have imaged my culture treated with MMS for a period of 6 hours and while observing the ...
1
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1answer
352 views

Where do kombucha SCOBYs get nitrogen?

Kombucha can be brewed even with tiny amounts of inocculate, such as the little bit of sediment at the bottom of store-bought kombuchas. Over 1-2 weeks, this can grow into an inch thick film covering ...
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1answer
146 views

How do I improve expression using the GAL1 promoter in S. cerevisiae above the “leaky” level I'm currently seeing?

I am attempting to express GFP in S. cerevisiae using the GAL1 promoter. I always grow an uninduced (in dextrose based SD medium) culture alongside my induced (in galactose based SD medium) culture. ...
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1answer
120 views

Using PGAL10 promoter to overexpress specific yeast genes: How to?

I was reading a poster about expression boosting for Artemesinin production in yeast and it had this line: PGAL1 and PGAL10 have been used for the overexpression of all genes from the ...
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2answers
95 views

yeast protein secondary structure

i have a fasta file of yeast orfs (from the SGD database) and i need to find out(predicted) secondary structure/classification for all of them (so ~6K queries and doing this by hand on numerous ...
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1answer
73 views

Book on yeast reproduction, evolution and on the use of yeast as model organism

I am looking for a good book in: Yeast reproduction mating types Recombination mating type determination mechanism Yeast evolution Yeast as model organism and its use in experimental biology It ...
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1answer
90 views

Isoprenoid Diphosphate Concentration in Yeast saccharomyces cerevisiae

Isoprenoid Diphosphate(IPP) is an important metabolites which is precursor in lot of secondary metabolites like Dolichol diphosphate, ubiquinone, prenylated proteins and carotenoid (not synthesized ...
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1answer
104 views

Carotenoid biosynthesis in yeast

Does Budding Yeast Sacchromyces cerevisiae produces significant amount of carotenoids? Have anybody estimated the ratio of flux going in branches 1. Cholesterol synthesis(via squalene) 2. Coenzyme Q6 ...
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0answers
22 views

Species diversity in cheese and yoghurt?

There have been studies on the number of species on humans and in various other environments. I was wondering how many species including: viruses, bacteria, yeasts, and fungi inhabit ordinary farm ...