1975年12月4日 · Methyl methanesulfonate produces many depurinations and practically no cross-linked DNA molecules, whereas it is the opposite with HNO 2. It is concluded that the loss of HNO 2 -deaminated purines is of little importance and that apurinic sites are not the precursors of the cross-links in DNA treated by HNO 2.

亚硝酸（HNO2）及其盐中N原子具有中间氧化态+3，虽然它们既具有氧化性，又具有还原性，但以氧化性为主。 它可以引起氧化脱氨作用，使胞嘧啶（C）转化成尿嘧啶（U），发生碱基转换。 在以后的复制周期中，U与A配对，代替了G与C的配对。 所以在下一个A-T配对的复制周期中，G-C对被A-T对代替（亚硝酸的氧化脱氨作用也能引起A-T到G-C的反向转换作用）。 亚硝酸可使胞嘧啶脱氧化氨基变成尿嘧啶（C→U） 人类的遗传物质DNA由A、T、C和G四种碱基组成，其 …

At least five major DNA repair pathways—base excision repair (BER), nucleotide excision repair (NER), mismatch repair (MMR), homologous recombination (HR) and non-homologous end joining (NHEJ)—are active throughout different stages of the cell cycle, allowing the cells to repair the DNA damage.

Figure 1 shown how expose of DNA to nitrous acid can convert the base adenine (A) to a form that no longer pair with thymine (T) but instead pairs with cytosine (C). When DNA containing such...

2023年12月1日 · Deoxyinosine occurs in DNA by spontaneous deamination of adenine or by incorporation of dITP during replication. Hypoxanthine residues (HX) are mutagenic and give rise to A-T-->G-C transition. They are substrates for the Escherichia coli product of the alkA gene, the 3-methyl-adenine-DNA glycosyl …

2009年6月17日 · Nitrous acid is a mutagenic agent. It can induce interstrand cross-links in duplex DNA, preferentially at d(CpG) steps: two guanines on opposite strands are linked via a single shared exocyclic imino group. Recent synthetic advances have led to the production of large quantities of such structurally homogenous cross-linked duplex DNA.

2024年4月11日 · 在碱性条件下，NTG会形成 重氮甲烷 (CH2N2)，它是引起致死和突变的主要原因。 它的效应很可能是CH2N2对DNA的 烷化作用 引起的。 NTG诱变根据《遗传学综合实验》介绍，具体操作步骤如下:

A common deaminating agent, i.e. nitrous acid (HNO2), replaces an -NH2 or amino group with an –OH or ether group, thereby altering the DNA bare pairing. In simple words, deaminating agents convert the amino group of the bases into keto acids through oxidative deamination.

hno2还能造成dna双链间的交联而引起遗传效应。 叠氮化钠(NaN3) 是一种呼吸抑制剂，能引起 基因突变 ，可获得较高的突变频率，而且无残毒。 新手上路

DNA containing interstrand cross-links resulting from reaction with nitrous acid has been used in an attempt to gain insight into the process of transformation of Bacillus subtilis. DNA reisolated from a competent auxotrophic culture after 30 min exposure to cross-linked prototrophic DNA showed no heat-stable prototrophic transforming activity.