Table 3.
The half inhibitory concentration (IC50) values (nM) for inhibition of serine/threonine protein phosphatases (PPs) by MC congeners.
| Entry a | Microcystin | Type of PP | Origin of PP | IC50 | Reference |
|---|---|---|---|---|---|
| 7 | MC-LA | PP1 | Rabbit muscle | 2.3 | [237] |
| PP2A | Human hepatocytes | 0.56 | [238] | ||
| PP2A | Rabbit muscle | 0.05 | [237] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.161 ± 0.002 | [239] | ||
| 14 | MC-LV | PP1 | Rabbit skeletal muscle | 0.06–0.45 | [133] |
| 17 | MC-LL | PP1 | Rabbit skeletal muscle | 0.06–0.45 | [133] |
| 25 | [D-Asp3,Dha7] MC-LR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.254 ± 0.004 | [239] |
| 34 | MC-LM | PP1 | Rabbit skeletal muscle | 0.06–0.45 | [133] |
| 39 | [D-Asp3]MC-LR | PP2A | Rabbit skeletal muscle | 0.09 | [215] |
| 40 | [D-Asp3,(E)-Dhb7]MC-LR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.201 ± 0.003 | [239] |
| 41 | [D-Asp3,(Z)-Dhb7]MC-LR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.16 ± 0.01 | [239] |
| 42 | [Dha7]MC-LR | PP1 | Rabbit skeletal muscle | 0.54–5 | [240,241] |
| PP2A | Bovine kidney | 0.11 ± 0.04 | [241] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.167 ± 0.003 | [239] | ||
| 43 | [DMAdda5]MC-LR | rPP1c | Recombinant rabbit skeletal muscle PP1 | 1.5 | [240] |
| 52 | MC-LF | rPP1c | Recombinant rabbit skeletal muscle PP1 | 1.8 | [224] |
| PP1 | Rabbit skeletal muscle | 0.06–0.45 | [133] | ||
| PP2A | Human hepatocytes | 0.57 | [238] | ||
| PP2A | Human red blood cells | 1.1 | [224] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.10 ± 0.02 | [239] | ||
| 66 | MC-LR | PP1 | Rabbit muscle | 0.1–1.9 | [215,217,237,240,241,242,243,244,245] |
| PP1 | Chicken gizzard myosin B | 6 | [246] | ||
| PP1 | Liver of grass carp | 0.90 | [247] | ||
| rPP1c | Recombinant rabbit skeletal muscle PP1 | 1.2 | [224] | ||
| PP2A | Rabbit skeletal muscle | 0.04–0.5 | [215,217,237,243,248] | ||
| PP2A | Human hepatocytes | 0.46 | [238] | ||
| PP2A | Human erythrocytes | 0.03–2.2 | [241,242,249,250] | ||
| PP2A | Bovine heart | 0.05-2 | [241,246,251] | ||
| PP2A | Bovine kidney | 0.2 ± 0.1 | [241] | ||
| PP2A | Mouse brain | 0.28–3.15 | [218,247,252,253] | ||
| PP2A | Liver of grass carp | 0.28 | [247] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.032 ± 0.004 | [239] | ||
| 68 | [(6Z)-Adda5]MC-LR | PP2A | Mouse brain | 80 | [252] |
| rPP1c | Recombinant rabbit skeletal muscle PP1 | >100 | [240] | ||
| 83 | MC-LY | PP2A | Human hepatocytes | 0.34 | [238] |
| 89 | [D-Asp3,ADMAdda5]MC-LR | PP2Ab | 4 | [178] | |
| 94 | [D-Glu(OMe)6]MC-LR | rPP1c | Recombinant rabbit skeletal muscle PP1 | >100 | [240] |
| 97 | [D-Asp3,Dha7]MC-RR | rPP1c | Recombinant rabbit skeletal muscle PP1 | 0.22 ± 0.01 | [239] |
| 129 | [D-Asp3]MC-RR | PP2A rPP2Ac |
Human red blood cells Recombinant human PP2A catalytic subunit |
0.45–11.5 0.30 ± 0.01 |
[254] [239] |
| 130 | [Dha7]MC-RR | PP1 | Rabbit muscle | 8.3 ± 0.8 | [241] |
| PP2A | Bovine kidney | 4 ± 1 | [241] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.29 ± 0.01 | [239] | ||
| PP1 | Rabbit skeletal muscle | 2.6–5.7 | [254] | ||
| 131 | [D-Asp3,(E)-Dhb7]MC-RR | PP1 | Rabbit skeletal muscle | 1.8–56.4 | [215,254] |
| PP2A | Rabbit skeletal muscle | 2.4 | [215] | ||
| PP2A | Human red blood cells | 17.9–49.4 | [254] | ||
| 135 | MC-LW | rPP1c | Recombinant rabbit skeletal muscle PP1 | 1.9 | [224] |
| PP2A | Human hepatocytes | 0.29 | [238] | ||
| PP2A | Human red blood cells | 1.1 | [224] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.114 ± 0.003 | [239] | ||
| 142 | MC-FR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.069 ± 0.003 | [239] |
| 149 | [Dha7]MC-YR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.379 ± 0.003 | [239] |
| 164 | [D-Leu1]MC-LR | PP1 | Recombinant rabbit skeletal muscle PP1 | 0.5–4.43 | [167,168] |
| 168 | MC-RR | PP1 | Rabbit skeletal muscle | 0.68 | [215] |
| PP1 | Chicken gizzard myosin B | 3 | [246] | ||
| PP1 | Liver of grass carp | 3.60 | [247] | ||
| rPP1c | Recombinant rabbit skeletal muscle PP1 | 1.5 | [224] | ||
| PP2A | Human red blood cells | 0.241–175 | [241,249,250] | ||
| PP2A | Human hepatocytes | 0.60 | [238] | ||
| PP2A | Mouse brain | 0.72–1.4 | [218,224,247,252] | ||
| PP2A | Bovine cardiac muscle | 1 | [246] | ||
| PP2A | Bovine Kidney | 10 ± 2 | [241] | ||
| PP2A | Rabbit skeletal muscle | 0.1 | [215] | ||
| PP2A | Liver of grass carp | 0.64 | [247] | ||
| rPP2Ac | Recombinant human PP2A catalytic subunit | 0.056 ± 0.002 | [239] | ||
| 169 | [(6Z)-Adda5]MC-RR | rPP2Ac | Recombinant human PP2A catalytic subunit | 10.1 ± 0.3 | [239] |
| PP2A | Mouse brain | 80 | [252] | ||
| 183 | [D-Asp3]MC-HtyR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.098 ± 0.006 | [239] |
| 185 | [D-Asp3,(E)-Dhb7]MC-HtyR | rPP2Ac | Recombinant human PP2A catalytic subunit |
0.122 ± 0.005 | [239] |
| 186 | [D-Asp3,(Z)-Dhb7]MC-HtyR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.110 ± 0.008 | [239] |
| 188 | MC-YR | PP1 PP1 PP2A PP2A PP2A PP2A PP2A PP2A rPP2Ac |
Rabbit skeletal muscle Liver of grass carp Human red blood cells Human hepatocytes Bovine kidney Rabbit skeletal muscle Mouse brain Liver of grass carp Recombinant human PP2A catalytic subunit |
1.0 0.90 0.26–9.0 0.84 0.09 ± 0.02 0.26 0.39–1.3 0.40 0.125 ± 0.005 |
[215] [247] [241,249,250] [238] [241] [215] [218,247] [247] [239] |
| 242 | MC-WR | rPP2Ac | Recombinant human PP2A catalytic subunit | 0.18 ± 0.01 | [239] |
| 251 | [D-Asp3,ADMAdda5,Dhb7]MC-HtyR | PP1 | Rabbit skeletal muscle | 0.15–0.24 | [254] |
| PP2A | Human red blood cells | 0.06 | [254] | ||
| PP2A | Bovine heart | 0.06 | [251] | ||
| PP4 | Porcine testis | 0.04 | [251] | ||
| PP5 | Recombinant human PP5 expressed in E. coli | 0.5 | [251] |