urea + 4-aminobutanoate => 4-guanidinobutanoate + H2O
urea + 4-aminobutanoate => 4-guanidinobutanoate + h2o
urea + 4-aminobutanoate => 4-guanidinobutanoate + H2O
urea + 4-aminobutanoate => 4-guanidinobutanoate + h2o