The usual concentration is 0.05-0.5 mol/L, and the action time is 5-60 minutes.

Be careful, that thing is highly toxic and carcinogenic.

Artificial chemical mutagenesis technology:

Chemical mutation technology refers to the use of certain chemicals to improve the natural mutation rate of organisms. These chemicals are called "chemical mutagens". Its characteristics are: strong operability, simplicity and clarity; Strong specificity, which can mutate some bases located on DNA; Offspring is easy to inherit stably, and generally it can be stable in F3 generation; The application of genetic markers is the basis of cell fusion technology.

There are five main types of mutagens, and their characteristics, action mechanisms and applications are as follows:

1, alkylating agent: Alkylation of some bases, such as methylated guanylic acid, can affect the transcription of mRNA, thus disrupting the expression of protein, recombining protein and changing its characters. Clinical application of such substances as anticancer drugs has a strong killing effect on cancer cells, so when applied to plants, we should also pay attention to its powerful killing effect.

Mainly: ethyl methanesulfonate (EMS), which is the most commonly used mutagen. We use it as a genetic marker of fungi, and the mutation rate is very high. The usual concentration is 0.05-0.5 mol/L, and the action time is 5-60 minutes. This substance is highly carcinogenic and volatile, and 5% sodium thiosulfate can be used as a terminator and antidote. Price of Six Sigma Company: 80 yuan /25ml.

Diethyl sulfate (DMS) is also commonly used, but it is rarely used at present because of its strong toxicity, and its mechanism and usage are basically the same as EMS. It belongs to drama drugs and belongs to the public security bureau.

Ethylene imine, the output is small and it is difficult to buy. As long as it is used in a large number of mutation breeding, the concentration is 0.000 1-0. 1%, which is highly carcinogenic! Buffer configuration is required for use.

As an anticancer drug, nitrogen mustard hydrochloride can be bought from pharmacies, but some places must have a prescription from the chief physician.

Generally, it is an injection, which can be used for 5- 10min with a little dilution, and glycine can be used as a terminator and antidote.

Cyclophosphamide and nitrosoguanidine can also be used as mutagens, but they are rarely used.

2. Base analogues: The molecular structure is similar to that of bases, which leads to DNA replication mismatch, mRNA transcription disorder, functional protein recombination and phenotypic change. The toxicity of these substances is relatively small, but the negative mutation rate is high, so it is often difficult to get good mutants. Mainly include: 6- bromouracil, 6-BudR, maleic hydrazide, 2- aminopurine, etc. It is also an anticancer drug, which can be bought in pharmacies with a little dilution.

3. Embedding agent: it is a commonly used one in molecular biology, with high induction rate. The principle is that the size of such molecules can be embedded in base molecules, leading to mismatch. The most commonly used: ethidium bromide (EB), highly carcinogenic! The price is expensive, but the mutation rate is high. Is commonly used in the laboratory reagent, can be bought in the actual biochemical store, price 1500 yuan/100mg.

4. Inorganic compounds: relatively easy to obtain, with general effect and less danger. Commonly used: lithium chloride, white powder, mixed with 0. 1-0.5% solution for 30 min-2 days. You can go to the chemical store to buy: 120 yuan/500g.

Nitrite: There is no ready-made commodity. This substance is used now because it decomposes easily. Sodium nitrite and hydrochloric acid are commonly used preparations. Mixing sodium nitrite to a concentration of 0.0 1-0. 1mol/L, and adding hydrochloric acid with the same concentration and volume when using.

Hydrogen peroxide: also known as hydrogen peroxide, the effect is not good, so it is rarely used.

5 others: reducing agent hydroxylamine hydrochloride acts on C, making G-C become A-T, which is also commonly used and can be bought. Usage concentration: 0. 1-0.5% for 60 minutes to 2 hours. Cheaper.

Alkaloids: such as vinblastine, colchicine, camptothecin, etc.

The above mutagens are carcinogens, and care must be taken when using them. Usually used for seed soaking, the best method is to add mutagens to the culture medium of tissue culture, and the mutation rate is the highest.

It is very harmful to human body and has a certain carcinogenic effect. Strictly protect the operation, and don't let the medicine touch the skin. Used tools should also be strictly collected and isolated to prevent mistakes.

Second, the types and mechanism of common chemical mutagens

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(1) alkylating agent

It is the most important mutagen to induce the mutation of cultivated crops. The reagent has one or more active alkyl groups. The substitution of hydrogen atoms of other molecules by alkyl groups is called "alkylation", so such substances are called alkylating agents.

Alkylating agents are divided into the following categories:

1. alkyl sulfonates and alkyl sulfates

Representative reagents: ethyl methanesulfonate (EMS) and diethyl sulfate (DES)

2. Nitroalkyl compounds

Representative reagents: nitrosoethyl urea (NEH), N- nitroso -N- ethyl urea (NEU).

3. Ethylenediamine and ethylene oxide

Representative: ethylenimine (EI)

4. Mustard gas

Nitrogen mustard and sulfur mustard

The mechanism of alkylating agent-alkylation focuses on nucleic acid, which leads to DNA breakage, deletion or repair.

(II) nucleic acid-based analog

These compounds have structures similar to those of DNA bases.

Representative agent:

5- bromouracil (BU) and 5- bromodeoxyuridine (BudR) are analogues of thymine (T).

2- aminopurine (AP) is an analogue of adenine (a).

Malehydrazide is an isomer of uracil.

Mechanism of action: As a component of DNA, it penetrates into DNA molecules, causing pairing errors in the process of DNA replication, thus causing biological variation.

(iii) Other mutagens

Nitrite can deamination purine or pyrimidine, change the structure and properties of nucleic acid, and cause DNA replication disorder. HNO2 _ 2 can also cause cross-linking between DNA double strands, causing genetic effects.

Sodium azide (NaN3) is a respiratory inhibitor, which can cause gene mutation with high mutation frequency and no residual toxicity.