Baldwin T O, Ziegler M M, Powers D A
Proc Natl Acad Sci U S A. 1979 Oct;76(10):4887-9. doi: 10.1073/pnas.76.10.4887.
The heterodimeric subunit structure of bacterial luciferase was demonstrated more than 10 years ago. The enzymes from both Beneckea harveyi and Photobacterium fischeri have since been studied in detail; they each consist of two nonidentical subunits, designated alpha and beta. Both are required for bioluminescence activity, with the active center apparently confined to the alpha subunit. Amino acid sequence analysis of the NH2 termini of the alpha and beta subunits of the B. harveyi and P. fischeri luciferases not only confirms the earlier observation that the alpha subunits are homologous but also demonstrates that the NH2-terminal sequences of the beta subunits of the luciferases from the two genera are homologous. Furthermore, within each luciferase, the NH2-terminal sequences of the alpha and beta subunits are similar, suggesting the possibility that the genes coding, for alpha and beta may have arisen by gene duplication, presumably prior to divergence of the lines leading to present-day luminous bacteria.
细菌荧光素酶的异源二聚体亚基结构早在10多年前就已得到证实。此后,对哈氏贝内克氏菌和费氏发光杆菌的酶进行了详细研究;它们各自由两个不同的亚基组成,分别称为α和β。生物发光活性需要这两个亚基,活性中心显然局限于α亚基。对哈氏贝内克氏菌和费氏发光杆菌荧光素酶α和β亚基的NH2末端进行氨基酸序列分析,不仅证实了早期观察到的α亚基是同源的,而且还表明这两个属的荧光素酶β亚基的NH2末端序列是同源的。此外,在每种荧光素酶中,α和β亚基的NH2末端序列相似,这表明编码α和β的基因可能是通过基因复制产生的,大概是在导致当今发光细菌的品系分化之前。