Sancar G B, Smith F W, Lorence M C, Rupert C S, Sancar A
J Biol Chem. 1984 May 10;259(9):6033-8.
We have determined the nucleotide sequence of a 2039-base pair segment of Escherichia coli chromosomal DNA containing the phr gene, which encodes deoxyribopyrimidine photolyase. The coding region of phr is 1416 base pairs and is preceded by regions homologous to consensus sequences for E. coli promoters and ribosome binding sites. The phr gene is preceeded by an open reading frame of 169 codons (orf169) which is transcribed in the same direction. The proximity of orf169 to phr suggests that both are members of a single operon containing one or more internal promoters allowing differential expression of phr. An unusually large number of rare or infrequently used codons are utilized in phr, which may contribute to the low copy number of photolyase. The sequence at the NH2 and COOH termini and the overall amino acid composition of mature photolyase, determined using purified protein, agrees with predictions based upon the nucleotide sequence. Photolyase consists of 471 amino acids and has a calculated molecular weight of 53,994.
我们已经确定了大肠杆菌染色体DNA中一段2039个碱基对的片段的核苷酸序列，该片段包含编码脱氧核糖嘧啶光解酶的phr基因。phr的编码区为1416个碱基对，其前面是与大肠杆菌启动子和核糖体结合位点的共有序列同源的区域。phr基因之前有一个169个密码子的开放阅读框（orf169），它与phr同向转录。orf169与phr的接近表明两者都是一个单一操纵子的成员，该操纵子包含一个或多个内部启动子，允许phr进行差异表达。phr中使用了异常大量的稀有或不常用密码子，这可能导致光解酶的低拷贝数。使用纯化蛋白确定的成熟光解酶的NH2和COOH末端序列以及整体氨基酸组成，与基于核苷酸序列的预测一致。光解酶由471个氨基酸组成，计算分子量为53994。
