2.2 SQUARE inside PROTEIN p0 inside PROTEIN p1 inside SIMPLE_MOLECULE Sphinganine inside SIMPLE_MOLECULE Sphingosine_space_1_minus_phosphate inside SIMPLE_MOLECULE Sphingosine STATE_TRANSITION Sphinganine Sphingosine c0 c2 STATE_TRANSITION Sphingosine Sphingosine_space_1_minus_phosphate c2 c1