label: lipid IVA (E. coli) + a 1-hexadecanoyl-2-acyl-sn-glycero-3-phosphocholine => lipid IVB (E. coli) + a 2-acyl-sn-glycero-3-phosphocholine
label_lc: lipid iva (e. coli) + a 1-hexadecanoyl-2-acyl-sn-glycero-3-phosphocholine => lipid ivb (e. coli) + a 2-acyl-sn-glycero-3-phosphocholine