Oba Yuichi, Ojika Makoto, Inouye Satoshi
Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa, Nagoya 464-8601, Japan.
Gene. 2004 Mar 31;329:137-45. doi: 10.1016/j.gene.2003.12.026.
This is the first identification of a long-chain fatty acyl-CoA synthetase in Drosophila by enzymatic characterization. The gene product of CG6178 (CG6178) in Drosophila melanogaster genome, which has a high sequence similarity to firefly luciferase, has been expressed and characterized. CG6178 showed long-chain fatty acyl-CoA synthetic activity in the presence of ATP, CoA and Mg(2+), suggesting a fatty acyl adenylate is an intermediate. Recently, it was revealed that firefly luciferase has two catalytic functions, monooxygenase (luciferase) and AMP-mediated CoA ligase (fatty acyl-CoA synthetase). However, unlike firefly luciferase, CG6178 did not show luminescence activity in the presence of firefly luciferin, ATP, CoA and Mg(2+). The enzymatic properties of CG6178 including substrate specificity, pH dependency and optimal temperature were close to those of firefly luciferase and rat fatty acyl-CoA synthetase. Further, phylogenic analyses strongly suggest that the firefly luciferase gene may have evolved from a fatty acyl-CoA synthetase gene as a common ancestral gene.
这是通过酶学特性首次在果蝇中鉴定出长链脂肪酰辅酶A合成酶。果蝇黑腹果蝇基因组中CG6178（CG6178）的基因产物，与萤火虫荧光素酶具有高度序列相似性，已被表达并进行了特性分析。CG6178在ATP、辅酶A和Mg(2+)存在的情况下表现出长链脂肪酰辅酶A合成活性，表明脂肪酰腺苷酸是一种中间体。最近，研究发现萤火虫荧光素酶具有两种催化功能，单加氧酶（荧光素酶）和AMP介导的辅酶A连接酶（脂肪酰辅酶A合成酶）。然而，与萤火虫荧光素酶不同，CG6178在萤火虫荧光素、ATP、辅酶A和Mg(2+)存在的情况下未表现出发光活性。CG6178的酶学特性，包括底物特异性、pH依赖性和最适温度，与萤火虫荧光素酶和大鼠脂肪酰辅酶A合成酶的特性相近。此外系统发育分析强烈表明，萤火虫荧光素酶基因可能从脂肪酰辅酶A合成酶基因进化而来，作为一个共同的祖先基因。
