Assessing Serratia spp. pathogenic potential from cryogenic habitats

• Published in: Russian Journal of Infection and Immunity
• Main Authors: A. E. Goncharov, A. P. Solomenny, A. L. Panin, S. E. Grigoriev, M. Yu. Cheprasov, Ya. A. Ahremenko, V. V. Kolodzieva, N. E. Goncharov, L. A. Kraeva
• Format: Article in Journal/Newspaper
• Language: Russian
• Published: Sankt-Peterburg : NIIÈM imeni Pastera 2021
• Subjects: serratia; biofilms; extreme environment; psychrotolerant bacteria; cold adaptation; virulence; microbiological monitoring; Infectious and parasitic diseases; RC109-216; Antarctic; East Antarctica; Laptev Sea; Guano; Khaya; Buor-Khaya; Tokarev; Tokarev Island; Adelie penguin; Alces alces; Antarc*; Antarctica; laptev; Pygoscelis adeliae; Yakutia
• Online Access: https://doi.org/10.15789/2220-7619-ASS-1593; https://doaj.org/article/4bcccb4db5c54f24b1e2fad6f8abced6

The genus Serratia are opportunistic bacteria widely spread in natural environment. At the same time, this bacterial genus consists of the species associated with outbreaks of nosocomial infections. Serratia species are found in extreme habitats, but pathogenic potential of polyextremophilic strains in this genus remains unexplored. The aim of this study was to compare the genomes of two Serratia strains isolated in polar regions, primarily examining genetic factors of virulence and adaptation to cryogenic environment. During the 56th Russian Antarctic Expedition the Serratia liquefaciens 72 strain was isolated from a guano sample of the Adelie Penguin (Pygoscelis adeliae) colony on Tokarev Island (Haswell Archipelago, East Antarctica). The Serratia fonticola 5l strain was isolated from the frozen carcass of moose (Alces alces) fossils found on the Buor-Khaya Peninsula near the Laptev Sea coast (Yakutia Region, Russia). The whole-genome sequencing of such strains allowed to reveal genetic structures evidencing about their successful adaptation to low temperatures. Thus, it was found that both genomes contain genes encoding the main cold shock proteins, phylogenetically close to the corresponding genes in the hypobarotolerant Serratia liquefaciens strain ATCC 27592. Furthermore, both strains bear a cluster of tc-fABCD genes determining the bacterial adhesion to epithelial tissues, and the genes for RTX toxins — adhesins, crucial factors of biofilm formation in pathogenic Gram-negative bacteria. Experimental studies confirmed the ability of Serratia liquefaciens 72 and Serratia fonticola 5l to actively form biofilms in a wide temperature range (from 6°C to 37°C). The results obtained indicate that the examined genus Serratia strains isolated in Arctica and Antarctica exert overall similar adaptation strategies to polar climate, including the ability to produce pili, show active adhesion, and biofilm formation under low temperatures. Genetic adaptive factors may also act as pathogenicity factors allowing ...