How to prepare YPD and YPDA medium, and do I need to adjust the pH?

How are YPD and YPDA media prepared and do I need to adjust my pH?

YPD or YEPD,: Yeast extract peptone dextrose medium (1L), also known as yeast extract peptone glucose medium, and agar with agar is also called yeast peptone glucose (YPD) agar medium.

It is used for the cultivation of yeast.

Formula: 1% Yeast Extract (yeast paste), 2% peptone (peptone), 2% dextrose (glucose), if making solid medium, add 2% agar powder.

Preparation method: 1 Dissolve 10 Gyeast extract (yeast paste), 20 gpeptone (peptone) in 900ml water, add 20 g agar powder such as making plates.

2. High pressure 121 degrees for 20min

3 Add 100ml of 20 gdextrose (glucose) (glucose) (add after sterilization of glucose solution).

Note: After mixing the glucose, Yeast extract, and peptone solutions, chemical reactions may occur at high temperatures, resulting in changes in the composition of the medium, so they should be sterilized separately before mixing. Glucose can be filtered and sterilized, or it can be sterilized at 115 15min.

Another recipe for YPD:

2% trypton (pancreptone or tryptone %dextrose (glucose) (glucose), if the medium is solid, add 2% agar powder, 115 15min sterilization. Liquid YPD medium can be stored at room temperature; Agar YPD plates can be stored at 4 months for several months. Add Zeocin 100ug ml to become YPDZ medium, which can be stored under 4 conditions for 1 2 weeks.

YPEG: Except for 3% ethanol and 3% glycerol instead of glucose as a carbon source, the other components are the same as YPD

YPDZ is the addition of Zeocin antibiotic to YPD.

YPDA is the addition of adenine sulfate to YPD.

The yeast two-hybrid system is an efficient and rapid method for analyzing protein-protein interactions, which has many applications but still has some limitations. Protein-protein interactions are localized in the nucleus by the two-hybrid system, while many protein-protein interactions rely on post-translational processes such as glycosylation and disulfide bond formation, which cannot be performed in the nucleus. In addition, the correct folding and function of some proteins depend on the assistance of other non-yeast proteins, which limits the study of certain extracellular proteins and cell membrane receptor proteins.

An important problem with yeast two-hybrid systems is false positives. Because some proteins themselves have the function of activating transcription or exert transcriptional activation when expressed in yeast, the DNA-binding domain hybridization protein can activate transcription in the absence of a specific activation domain. In addition, some proteins contain regions with low affinity for multiple proteins, which can form stable complexes with other proteins, resulting in the expression of reporter genes and false-positive results.

YPD1% Yeast Extract (yeast paste), 2% Peptone (peptone), 2% Dextrose (glucose), and if making solid medium, add 2% agar powder.

YPDS1% Yeast Extract (yeast paste), 2% Peptone (peptone), 2% Dextrose (glucose), 1mol L of Sorbitol (sorbitol), if making solid medium, add 2% agar powder.

The preparation method of YPDA medium is as follows:

20g peptone, 10g yeast extract, 2g glucose dissolved in double distilled water, 15ml 0.2 percent adenine solution, fixed volume to 1L, 120 autoclaved for 15 minutes, store at room temperature.

Solid part: 2% agar powder was added to YPDA liquid medium, autoclaved for 120 minutes for 15 min, plated, and stored after coagulation.

The types of media are as follows:

1. Basal medium: broth. Contains beef infusion and peptone. It is widely used for the enrichment and detection of bacteria, and is also the basic component for the preparation of other culture media.

2. Nutrient medium: special components are added to the basal medium for the growth of bacteria with high nutritional requirements and bacteria requiring special growth factors. Such as blood agar plates, chocolate blood plates.

3. Identification medium: observe the different products released by the decomposition substrate during the growth of bacteria, and identify the bacteria through the indicator Xiansen manuscript. Such as sugar fermentation tubes, K-disaccharide iron agar (KIA), eosin-methylene blue agar and power-indole-urea (MIU) medium.

4. Select the medium: add inhibitors to inhibit the growth of miscellaneous bacteria in the specimens, which is helpful for the growth of the selected bacterial species (SS agar this potato filial piety).

5. Special medium: anaerobic medium and bacterial L-type medium (blister medium, sodium thioglycolate medium, hypertonic medium), etc. <>