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 . Twist knots are some of the most common conformations of these products and they can act as substrates for further rounds of site-specific recombination .