Before revision: Site-specific recombination is an important cellular process that yields a variety of knotted and catenated DNA products on supercoiled circular DNA  . Twist knots are some of the most common conformations of these products  .
After revision: Site-specific recombination is an important cellular process that yields a variety of knotted and catenated DNA products on supercoiled circular DNA molecules can yield a variety of knots and catenanes . Twist knots are some of the most common conformations of these products .