ITM-CNR
and Department of Chemical Sciences, University of Padova, Via Marzolo
1, 35131 Padova, Italy
Department
of Chemical and Pharmaceutical Sciences, University of Trieste, Via Giorgieri 1, 34127 Trieste, Italy
Department
of Biology, University of Padova, via Bassi 58b, 35131 Padova, Italy
The coupling of a polycationic Mn(III)-porphyrin, with a dinuclear Mn
2
(II,II)L
2
core (HL = 2-{[[di(2-pyridyl)methyl](methyl)amino]methyl}phenol), results in a dual Superoxide Dismutase (SOD) and Catalase (CAT) functional analogue,
Mn
2
L
2
P
n
+
, enabling a detoxification cascade of the superoxide anion and hydrogen peroxide into benign H
2
O and O
2
. The SOD/CAT artificial manifolds, joined in one asset, exhibit a peak catalytic performance under physiological conditions, with log
k
cat
(O
2
• –
) ≥ 7 and
k
cat
(H
2
O
2
)/
K
M
= 1890. The dual-enzyme (dizyme) concept allows for a built-in self-protection against the irreversible bleaching of the porphyrin unit (>75% protection), readily induced by H
2
O
2
(200 μM, 20 equiv, in buffer solution, pH 7.8). We show herein that incubation of the photosynthetic green algae,
Chlamydomonas reinhardtii,
with the synthetic dizyme (as low as 0.1 μM), prevents H
2
O
2
accumulation under high-light illumination conditions, thus providing antioxidant surveillance and photoprotection.
中文翻译：
聚阳离子Mn（III）-卟啉与双核Mn
2
（II，II）L
2
核的偶联（HL = 2-{[[[[（（2-（吡啶基）甲基）] [甲基]氨基]甲基}苯酚） ，产生双重超氧化物歧化酶（SOD）和过氧化氢酶（CAT）功能类似物
Mn
2
L
2
P
n
+
，使超氧阴离子和过氧化氢解毒级联为良性H
2
O和O
2
。SOD / CAT人工歧管结合在一起，在生理条件下显示出最高的催化性能，log
k
cat
（O
2
•–
）≥7和
k
cat
（H
2
O
2
）/
K
M
=1890。双酶（二酶）概念可实现针对H
2
O
2
（200容易诱导的卟啉单元不可逆漂白的内置自我保护作用（> 75％的保护作用）。μM，20当量，在pH 7.8的缓冲溶液中）。我们在本文中显示，光合作用的藻类（
莱茵衣藻）
与合成的二酶（低至0.1μM）一起孵育可防止H
2
O
2
在强光照射条件下积累，从而提供了抗氧化剂监测和光保护作用。
