Sevilla C L, Mahle N H, Eliezer N, Uzieblo A, O'Hara S M, Nokubo M, Miller R, Rouzer C A, Marnett L J
Proteins International, Rochester Hills, Michigan 48309, USA.
Chem Res Toxicol. 1997 Feb;10(2):172-80. doi: 10.1021/tx960120d.
Malondialdehyde (MDA), an endogenous product of lipid peroxidation and prostaglandin biosynthesis, is mutagenic in bacterial and mammalian cells and carcinogenic in rats. In order to determine whether MDA-modified bases are formed in nucleic acids in vivo, sensitive immunoassays to detect MDA-DNA and MDA-RNA adducts are being developed in our laboratory. Murine monoclonal antibodies reactive with the MDA-deoxyguanosine adduct 3-beta-D-erythro-pentofuranosylpyrimido[1,2-alpha]purin-10(3H)-one (M1G-R) were prepared and characterized. Several MDA-modified nucleosides and deoxynucleosides and structural analogs were synthesized and characterized and were compared as competitive inhibitors in enzyme-linked immunosorbent assays (ELISAs). Less than 5 fmol of M1G in MDA-modified DNA was detected in a direct ELISA, and antibody binding to the modified DNA was competitively inhibited by free M1G-dR. DNA from Salmonella typhimurium treated with concentrations of MDA that induce reversion to histidine prototrophy was enzymatically digested, and M1G-dR was quantitated by competitive ELISA. Over a range of MDA concentrations from 10 to 40 mM, the level of M1G residues in bacterial DNA increased from 0.2 to 2.5/10(6) base pairs.
丙二醛（MDA）是脂质过氧化和前列腺素生物合成的内源性产物，在细菌和哺乳动物细胞中具有致突变性，在大鼠中具有致癌性。为了确定体内核酸中是否形成了MDA修饰的碱基，我们实验室正在开发灵敏的免疫测定法来检测MDA-DNA和MDA-RNA加合物。制备并表征了与MDA-脱氧鸟苷加合物3-β-D-赤藓糖基呋喃糖基嘧啶并[1,2-α]嘌呤-10（3H）-酮（M1G-R）反应的鼠单克隆抗体。合成并表征了几种MDA修饰的核苷、脱氧核苷及其结构类似物，并在酶联免疫吸附测定（ELISA）中作为竞争性抑制剂进行了比较。在直接ELISA中检测到MDA修饰的DNA中M1G的含量低于5飞摩尔，游离的M1G-dR竞争性抑制抗体与修饰DNA的结合。用能诱导回复为组氨酸原养型的MDA浓度处理鼠伤寒沙门氏菌的DNA，经酶切后，通过竞争性ELISA对M1G-dR进行定量。在10至40 mM的MDA浓度范围内，细菌DNA中M1G残基的水平从0.2增加到2.5/10（6）个碱基对。
