TY  - JOUR
AU  - Vukotić, Goran
AU  - Obradović, Mina
AU  - Novović, Katarina
AU  - Di Luca, Mariagrazia
AU  - Jovčić, Branko
AU  - Fira, Đorđe
AU  - Neve, Horst
AU  - Kojić, Milan
AU  - McAuliffe, Olivia
PY  - 2020
UR  - http://intor.torlakinstitut.com/handle/123456789/721
AB  - Acinetobacter baumanniiis a leading cause of healthcare-associated infections worldwide. Its various intrinsic and acquired mechanisms of antibiotic resistance make the therapeutic challenge even more serious. One of the promising alternative treatments that is increasingly highlighted is phage therapy, the therapeutic use of bacteriophages to treat bacterial infections. Two phages active against nosocomial carbapenem-resistantA. baumanniistrain 6077/12, vB_AbaM_ISTD, and vB_AbaM_NOVI, were isolated from Belgrade wastewaters, purified, and concentrated using CsCl gradient ultracentrifugation. The phages were screened against 103 clinical isolates ofA. baumanniifrom a laboratory collection and characterized based on plaque and virion morphology, host range, adsorption rate, and one-step growth curve. Given that phage ISTD showed a broader host range, better adsorption rate, shorter latent period, and larger burst size, its ability to lyse planktonic and biofilm-embedded cells was tested in detail. Phage ISTD yielded a 3.5- and 2-log reduction in planktonic and biofilm-associated viable bacterial cell count, respectively, but the effect was time-dependent. Both phages produced growing turbid halos around plaques indicating the synthesis of depolymerases, enzymes capable of degrading bacterial exopolysaccharides. Halos tested positive for presence of phages in the proximity of the plaque, but not further from the plaque, which indicates that the observed halo enlargement is a consequence of enzyme diffusion through the agar, independently of the phages. This notion was also supported by the growing halos induced by phage preparations applied on pregrown bacterial lawns, indicating that depolymerizing effect was achieved also on non-dividing sensitive cells. Overall, good rates of growth, fast adsorption rate, broad host range, and high depolymerizing activity, as well as antibacterial effectiveness against planktonic and biofilm-associated bacteria, make these phages good candidates for potential application in combatingA. baumanniiinfections.
PB  - Frontiers Media Sa, Lausanne
T2  - Frontiers in Medicine
T1  - Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-ResistantAcinetobacter baumannii
VL  - 7
DO  - 10.3389/fmed.2020.00426
ER  - 

@article{
author = "Vukotić, Goran and Obradović, Mina and Novović, Katarina and Di Luca, Mariagrazia and Jovčić, Branko and Fira, Đorđe and Neve, Horst and Kojić, Milan and McAuliffe, Olivia",
year = "2020",
abstract = "Acinetobacter baumanniiis a leading cause of healthcare-associated infections worldwide. Its various intrinsic and acquired mechanisms of antibiotic resistance make the therapeutic challenge even more serious. One of the promising alternative treatments that is increasingly highlighted is phage therapy, the therapeutic use of bacteriophages to treat bacterial infections. Two phages active against nosocomial carbapenem-resistantA. baumanniistrain 6077/12, vB_AbaM_ISTD, and vB_AbaM_NOVI, were isolated from Belgrade wastewaters, purified, and concentrated using CsCl gradient ultracentrifugation. The phages were screened against 103 clinical isolates ofA. baumanniifrom a laboratory collection and characterized based on plaque and virion morphology, host range, adsorption rate, and one-step growth curve. Given that phage ISTD showed a broader host range, better adsorption rate, shorter latent period, and larger burst size, its ability to lyse planktonic and biofilm-embedded cells was tested in detail. Phage ISTD yielded a 3.5- and 2-log reduction in planktonic and biofilm-associated viable bacterial cell count, respectively, but the effect was time-dependent. Both phages produced growing turbid halos around plaques indicating the synthesis of depolymerases, enzymes capable of degrading bacterial exopolysaccharides. Halos tested positive for presence of phages in the proximity of the plaque, but not further from the plaque, which indicates that the observed halo enlargement is a consequence of enzyme diffusion through the agar, independently of the phages. This notion was also supported by the growing halos induced by phage preparations applied on pregrown bacterial lawns, indicating that depolymerizing effect was achieved also on non-dividing sensitive cells. Overall, good rates of growth, fast adsorption rate, broad host range, and high depolymerizing activity, as well as antibacterial effectiveness against planktonic and biofilm-associated bacteria, make these phages good candidates for potential application in combatingA. baumanniiinfections.",
publisher = "Frontiers Media Sa, Lausanne",
journal = "Frontiers in Medicine",
title = "Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-ResistantAcinetobacter baumannii",
volume = "7",
doi = "10.3389/fmed.2020.00426"
}

Vukotić, G., Obradović, M., Novović, K., Di Luca, M., Jovčić, B., Fira, Đ., Neve, H., Kojić, M.,& McAuliffe, O.. (2020). Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-ResistantAcinetobacter baumannii. in Frontiers in Medicine
Frontiers Media Sa, Lausanne., 7.
https://doi.org/10.3389/fmed.2020.00426

Vukotić G, Obradović M, Novović K, Di Luca M, Jovčić B, Fira Đ, Neve H, Kojić M, McAuliffe O. Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-ResistantAcinetobacter baumannii. in Frontiers in Medicine. 2020;7.
doi:10.3389/fmed.2020.00426 .

Vukotić, Goran, Obradović, Mina, Novović, Katarina, Di Luca, Mariagrazia, Jovčić, Branko, Fira, Đorđe, Neve, Horst, Kojić, Milan, McAuliffe, Olivia, "Characterization, Antibiofilm, and Depolymerizing Activity of Two Phages Active on Carbapenem-ResistantAcinetobacter baumannii" in Frontiers in Medicine, 7 (2020),
https://doi.org/10.3389/fmed.2020.00426 . .