This paper reported the heme-containing enzyme-like catalytic activities of 15 water-soluble metalloporphyrins (M-Ps) produced from three metal ions (Fe, Mn and Co) and five porphophine ligands, i.e. porphyrin IX, meso-tetrakis(p-sulfonatophenyl) porphophine (TPPS4), meso-tetrakis(4-carboxy-phenyl)porphophine (TCPP), meso-tetrakis[4-(N-trimethyl)aminophenyl]porphophine (TTMAPP) and meso-tetrakis(4-N-methylpyridinium)porphophine (TMPyP). Their catalytic activities of catalase, peroxidase and cytochrome P-450 on the typical reactions were systematically studied and compared. The results indicated that the metalloporphyrins with Fe and Mn as central ions show high catalytic activities of catalase and peroxidase at pH range of 10.5-11.5, and among them Fe-TMPyP and Fe-TTMAPP have the highest catalytic capability, while all Co-porphyrins have weak activities. Interestingly, only Mn-TMPyP of the 15 metalloporphyrins shows relatively high cytochrome, P-450-like activity. The presence of imidazole has enhancement effects to different extent on the peroxidase-like activities of these metalloporphyrins and negligible effects on catalase-like activities. (C) 2002 Elsevier Science B.V. All rights reserved.