Lawton M P, Cashman J R, Cresteil T, Dolphin C T, Elfarra A A, Hines R N, Hodgson E, Kimura T, Ozols J, Phillips I R
National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina 27709.
Arch Biochem Biophys. 1994 Jan;308(1):254-7. doi: 10.1006/abbi.1994.1035.
A nomenclature based on comparisons of amino acid sequences is proposed for the members of the mammalian flavin-containing monooxygenase (FMO) gene family. This nomenclature is based on evidence of a single gene family composed of five genes. The percentage identities of the amino acid sequences of the five known forms of mammalian FMO are between 52 and 57% in rabbit and between 50 and 58% across species lines. The identities of all orthologs are greater than 82%. There is no evidence for multiple, highly related forms of the enzyme or for more than one mammalian FMO gene family. In the proposed system, the mammalian flavin-containing monooxygenase gene family is designated as "FMO" and the individual genes are distinguished by an Arabic numeral. The FMOs known as the "liver" and "lung" enzymes become FMO1 and FMO2, and the more recently described forms of the enzymes become FMO3, FMO4, and FMO5. Human FMO gene designations, FMO1 and FMO3, remain unchanged, but the gene designated FMO2 becomes FMO4. Following convention, the genes and cDNA designations will be italicized and the mRNA and protein designations will be nonitalicized. The purpose of the proposed nomenclature is to provide for the unambiguous identification of orthologous forms of mammalian FMOs, regardless of the species or tissue in question. The proposed classification considers only members of the mammalian flavin-containing monooxygenase gene family and has no bearing on the generally accepted definition of a multisubstrate flavin-containing monooxygenase.
针对哺乳动物含黄素单加氧酶（FMO）基因家族的成员，提出了一种基于氨基酸序列比较的命名法。该命名法基于由五个基因组成的单一基因家族的证据。在兔子中，哺乳动物FMO的五种已知形式的氨基酸序列的百分比同一性在52%至57%之间，跨物种线则在50%至58%之间。所有直系同源物的同一性大于82%。没有证据表明存在该酶的多种高度相关形式或不止一个哺乳动物FMO基因家族。在提议的系统中，哺乳动物含黄素单加氧酶基因家族被指定为“FMO”，各个基因则用阿拉伯数字区分。被称为“肝脏”和“肺”酶的FMO分别成为FMO1和FMO2，而最近描述的酶形式成为FMO3、FMO4和FMO5。人类FMO基因的指定FMO1和FMO3保持不变，但指定为FMO2的基因变为FMO4。按照惯例，基因和cDNA的指定将用斜体表示，mRNA和蛋白质的指定将不用斜体。提议的命名法的目的是为明确鉴定哺乳动物FMO的直系同源形式提供依据，而不论所涉及的物种或组织如何。提议的分类仅考虑哺乳动物含黄素单加氧酶基因家族的成员，与多底物含黄素单加氧酶的普遍接受定义无关。
