L-threonine + L-alanine => L-alanyl-L-threonine + H2O
l-threonine + l-alanine => l-alanyl-l-threonine + h2o
L-threonine + L-alanine => L-alanyl-L-threonine + H2O
l-threonine + l-alanine => l-alanyl-l-threonine + h2o