Shibata H, Yamazaki T
Department of Biology, Faculty of Science, Kyushu University, Fukuoka, Japan.
Jpn J Genet. 1994 Jun;69(3):251-8. doi: 10.1266/jjg.69.251.
A comparative study was done on the enzymological features of alpha-amylase among six sibling species belonging to the Drosophila melanogaster species subgroup. The pH optima were 7.6 for D. melanogaster, D. mauritiana and D. simulans and 7.4 for D. erecta, D. teissieri and D. yakuba. The temperature optima were commonly 37 C in all species studied. However, there are two types of temperature dependence; a strict one as observed in D. melanogaster, D. mauritiana and D. simulans, and a flat one as observed in D. erecta, D. teissieri and D. yakuba. These separations are consistent with the general phylogeny within this species subgroup. The substrate dependence was almost the same in all the species studied. The Vmax and Km were also estimated for each species. We found clear differences in the enzymological features between the species. Thus these differences might reflect an adaptation of the amylase enzyme system to speciation in this species subgroup.
对黑腹果蝇种亚组的六个姊妹种的α-淀粉酶的酶学特性进行了比较研究。黑腹果蝇、毛里求斯果蝇和拟果蝇的最适pH值为7.6，而直立果蝇、泰氏果蝇和雅库布果蝇的最适pH值为7.4。在所研究的所有物种中，最适温度通常为37℃。然而，存在两种温度依赖性；一种是在黑腹果蝇、毛里求斯果蝇和拟果蝇中观察到的严格依赖性，另一种是在直立果蝇、泰氏果蝇和雅库布果蝇中观察到的平缓依赖性。这些分类与该种亚组内的一般系统发育一致。在所研究的所有物种中，底物依赖性几乎相同。还估计了每个物种的Vmax和Km。我们发现不同物种之间在酶学特性上存在明显差异。因此，这些差异可能反映了淀粉酶酶系统对该种亚组物种形成的适应性。
