[noda]

I need your help someone can explain why in the enzymatic hydrolysis of racemic cis-lactone 7(table 1) at low conversion values one of the products is ester 7 (from ring fission) and in table 2 with trans-lactone 8 the only product was the lactonic acid( why there isn't ring fission)?
thank you and happy new year

[FeLiXe]

my guess:

with the cis form the enzyme can attack from the side where only hydrogens are

in the trans form there are big groups on both sides. so the enzyme can't attack from either side

the ester is always accessible