The role of Mn(II) in the radioresistance mechanism of Deinococcus radiodurans bacterium

Since its discovery, Deinoccocus radiodurans bacterium (Dr) has emerged as one of the most
radioresistant microorganism, which can withstand radiation doses greater than 10 KGy,
about 3000 times higher than the lethal dose in humans. The understanding of the cell
protection ability from radiation-induced death and the high antioxidant capacity opens
several potential applications in the field of medicine and biotechnology, as a remedy and
cure against radiation injury, in delaying aging and preventing cancer, or for bioremediation
of contaminated sites.
The mechanism of Dr defence, though not clearly interpreted, seems to involve Mn(II)
interaction with ROS-scavenging enzymes or ROS-scavenging complexes with non-enzymatic
small-molecule comprising carotenoids, amino acids, peptides and phosphate groups that
are crucial for protein protection from oxidative damage during irradiation and,
consequently, for Dr survival.
The presentation will focus on the role of Mn(II)-peptides and -proteins complexes in the
radioresistance mechanism of Dr, by using both a spectroscopic (in vitro) and bioinformatic
(in silico) approach [1,2].

References:
[1] Peana, M.; Medici, S.; Pangburn, H. A.; Lamkin, T. J.; Ostrowska, M.; Gumienna-
Kontecka, E.; Zoroddu, M. A., Manganese binding to antioxidant peptides involved in
extreme radiation resistance in Deinococcus radiodurans. Journal of inorganic
biochemistry 2016,164, 49-58.
[2] Peana, M.; Chasapis, C. T.; Simula, G.; Medici, S.; Zoroddu, M. A., A Model for
Manganese interaction with Deinococcus radiodurans proteome network involved in
ROS response and defense. Journal of Trace Elements in Medicine and Biology 2018.
DOI: 10.1016/j.jtemb.2018.02.001