Ohkuma M, Muraoka S, Tanimoto T, Fujii M, Ohta A, Takagi M
Department of Agricultural Chemistry, University of Tokyo, Japan.
DNA Cell Biol. 1995 Feb;14(2):163-73. doi: 10.1089/dna.1995.14.163.
Previously, we characterized three genes and presented evidence for an n-alkane-inducible cytochrome P450 (P450alk) multigene family in an n-alkane-assimilating and diploid-type yeast, Candida maltosa. In the present report, we isolated and characterized additional members of this gene family, including a total of thirteen P450alk-related sequences (eight genes and five of their alleles). Two sets, each consisting of two genes, were tandemly arranged in the genome. A gene replacement experiment showed that at least one gene had only a single allele in the genome. The determined nucleotide and the deduced amino acid sequences indicated that all had a characteristic constituent for P450s and exhibited amino acid identities from 94% to 37% to each other. Six genes showed relatively higher similarities to each other than to the other two genes and were thus classified into a subfamily. All the members of this subfamily were assigned to the same single chromosome, showing a good correlation between sequence similarity and chromosomal linkage. Although all the genes except for one were induced by n-alkane, their inducibilities by some other aliphatic carbon sources showed variabilities.
此前，我们对三个基因进行了表征，并提供了证据证明在同化正构烷烃的二倍体类型酵母麦芽糖假丝酵母中存在一个正构烷烃诱导型细胞色素P450（P450alk）多基因家族。在本报告中，我们分离并表征了该基因家族的其他成员，包括总共13个与P450alk相关的序列（8个基因及其5个等位基因）。基因组中有两组，每组由两个基因串联排列。基因置换实验表明，基因组中至少有一个基因只有一个等位基因。测定的核苷酸序列和推导的氨基酸序列表明，所有序列都具有细胞色素P450的特征性组成部分，彼此之间的氨基酸同一性为94%至37%。六个基因彼此之间的相似性相对高于与其他两个基因的相似性，因此被归为一个亚家族。该亚家族的所有成员都位于同一条单染色体上，表明序列相似性与染色体连锁之间存在良好的相关性。尽管除一个基因外的所有基因都受正构烷烃诱导，但它们对其他一些脂肪族碳源的诱导性存在差异。
