So, we have a problem here if we're thinking about keeping things at the lowest energy, so there's a lot of ring strain in the system.

现在有个问题,我们考虑要把能量降到最低，所以环上有许多应力。

麻省理工公开课 - 化学原理课程节选

It was found in strain R, a particular strain of E.coli, and it was the first one found, There's a nomenclature that's evolved for this.

酶被发现于R菌株,大肠杆菌中一种特别的菌株,又是被发现的第一种内切酶,有一种专门为此制定的命名法

耶鲁公开课 - 生物医学工程探索课程节选