Rational Redesign of Monoamine Oxidase A into a Dehydrogenase
to Probe ROS in Cardiac Aging
Luca Giacinto Iacovino
Nicola Manzella
Jessica Resta
Maria Antonietta Vanoni
Laura Rotilio
Leonardo Pisani
Dale Edward Edmondson
Angelo Parini
Andrea Mattevi
Jeanne Mialet-Perez
Claudia Binda
10.1021/acschembio.0c00366.s001
https://acs.figshare.com/articles/journal_contribution/Rational_Redesign_of_Monoamine_Oxidase_a_into_a_Dehydrogenase_to_Probe_ROS_in_Cardiac_Aging/12588168
Cardiac senescence
is a typical chronic frailty condition in the
elderly population, and cellular aging is often associated with oxidative
stress. The mitochondrial-membrane flavoenzyme monoamine oxidase A
(MAO A) catalyzes the oxidative deamination of neurotransmitters,
and its expression increases in aged hearts. We produced recombinant
human MAO A variants at Lys305 that play a key role in O<sub>2</sub> reactivity leading to H<sub>2</sub>O<sub>2</sub> production. The
K305Q variant is as active as the wild-type enzyme, whereas K305M
and K305S have 200-fold and 100-fold lower <i>k</i><sub>cat</sub> values and similar <i>K</i><sub>m</sub>. Under
anaerobic conditions, K305M MAO A was normally reduced by substrate,
whereas reoxidation by O<sub>2</sub> was much slower but could be
accomplished by quinone electron acceptors. When overexpressed in
cardiomyoblasts by adenoviral vectors, the K305M variant showed enzymatic
turnover similar to that of the wild-type but displayed decreased
ROS levels and senescence markers. These results might translate into
pharmacological treatments as MAO inhibitors may attenuate cardiomyocytes
aging.
2020-07-01 20:12:06
O 2 reactivity
K 305S
adenoviral vectors
K 305M
Rational Redesign
oxidative deamination
attenuate cardiomyocytes
mitochondrial-membrane flavoenzyme ...
wild-type enzyme
ROS levels
Lys 305
k cat values
Monoamine Oxidase
frailty condition
expression increases
K 305Q variant
quinone electron acceptors
K m
Probe ROS
O 2
Cardiac Aging Cardiac senescence
H 2 O 2 production
oxidative stress
K 305M MAO
senescence markers
K 305M variant
MAO inhibitors