Oba Yuichi, Iida Koichiro, Ojika Makoto, Inouye Satoshi
Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Japan.
Gene. 2008 Jan 15;407(1-2):169-75. doi: 10.1016/j.gene.2007.10.013. Epub 2007 Oct 13.
A homologous gene of beetle luciferase, AbLL (Agrypnus binodulusluciferase-like gene) was isolated from a Japanese non-luminous click beetle, A. binodulus, and its gene product was characterized. The identity of amino acid sequence deduced from AbLL with the click beetle luciferase from the Jamaican luminous click beetle, Pyrophorus plagiophthalmus, is 55%, which is higher than that between click beetle luciferase and firefly luciferase (approximately 48%). Phylogenetic analysis indicated that AbLL places in a clade of beetle luciferases, suggesting that AbLL is an orthologous gene of beetle luciferase. The gene product of AbLL (AbLL) has medium- and long-chain fatty acyl-CoA synthetase activity, but not luciferase activity. The fatty acyl-CoA synthetic activity was slightly inhibited in the presence of beetle luciferin, suggesting that AbLL has poor affinity for beetle luciferin. By comparing the amino acid residues of the catalytic domains in beetle luciferases with AbLL, the key substitutions for the luminescence activity in beetle luciferase will be proposed.
从日本非发光叩头虫双瘤阿蛴螬（Agrypnus binodulus）中分离出一种甲虫荧光素酶的同源基因AbLL（双瘤阿蛴螬荧光素酶样基因），并对其基因产物进行了表征。从AbLL推导的氨基酸序列与来自牙买加发光叩头虫（Pyrophorus plagiophthalmus）的叩头虫荧光素酶的同一性为55%，高于叩头虫荧光素酶与萤火虫荧光素酶之间的同一性（约48%）。系统发育分析表明，AbLL位于甲虫荧光素酶的一个进化枝中，这表明AbLL是甲虫荧光素酶的直系同源基因。AbLL的基因产物（AbLL）具有中链和长链脂肪酰辅酶A合成酶活性，但没有荧光素酶活性。在存在甲虫荧光素的情况下，脂肪酰辅酶A合成活性略有抑制，这表明AbLL对甲虫荧光素的亲和力较差。通过比较甲虫荧光素酶与AbLL催化结构域的氨基酸残基，将提出甲虫荧光素酶发光活性的关键取代。
