L-seryl-[myosin light chain] + phosphate => O-phospho-L-seryl-[myosin light chain] + H2O
l-seryl-[myosin light chain] + phosphate => o-phospho-l-seryl-[myosin light chain] + h2o
L-seryl-[myosin light chain] + phosphate => O-phospho-L-seryl-[myosin light chain] + H2O
l-seryl-[myosin light chain] + phosphate => o-phospho-l-seryl-[myosin light chain] + h2o