Naslov
Inhibition of Helicobacter pylori purine nucleoside phosphorylase and bacteria cell cultures with 2-chloro-6-substituted purines

Autori
Narczyk, M. ; Leščić Ašler, Ivana ; Wojtyś, M. ; Štefanić, Zoran ; Luić, Marija ; Jagusztyn- Krynicka, K. ; Bzowska, A.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, neobjavljeni rad, znanstveni

Skup
45th FEBS 2020 Congress Molecules of Life: Towards New Horizons

Mjesto i datum
Ljubljana, Slovenija, 03.07.2021. - 08.07.2021

Vrsta sudjelovanja
Poster

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
Helicobacter pylori ; purine nucleoside phosphorylase ; purine derivatives ; enzyme inhibition ; MIC values ; protein structure

Sažetak
Since its discovery in 1982, Helicobacter pylori was proven to be involved in development of several gastrointestinal diseases, including chronic gastritis, peptic ulcer disease, gastric cancer and MALT lymphoma. It is estimated that over half of the world's population is infected with this pathogen. Although it colonizes extremely hostile acid environment of human stomach, this bacterium has developed ways to persevere by adapting pH of its environment, burrowing into the mucus lining of the stomach, and employing high rate of mutations to develop antibiotic-resistant strains. Thus, there is a growing need for new drugs that could eradicate this pathogen. H. pylori lacks de novo purine synthesis genes and relies solely on the salvage pathway for acquisition of purines. This makes the enzymes of the salvage pathway promising targets for the development of new drugs. One of these enzymes is purine nucleoside phosphorylase (PNP), which catalyses the reversible phosphorolytic cleavage of the glycosidic bond of purine nucleosides in the presence of orthophosphate as a second substrate. We have previously produced H. pylori PNP in E. coli cells, characterized it kinetically and biochemically, and solved its 3D- structure. Here we present the results of inhibition studies of this enzyme. Several compounds were tested as potential inhibitors of H. pylori PNP. The highest inhibition levels were obtained with 2-chloro-6-substituted purines. Therefore, for these compounds detailed kinetic experiments were performed, which revealed that they inhibit H. pylori PNP through the mixed type mechanism with inhibition constants in low μM range. Complexes of enzyme with these inhibitors were crystallised by vapour diffusion method, X- ray diffraction data were collected at synchrotron (Elettra, Trieste, Italy) and 3D-structures solved by method of molecular replacement. The minimal inhibitory concentrations (MIC) of the best inhibitors vs. H. pylori 26695 strain were also determined.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Biologija, Biotehnologija u biomedicini (prirodno područje, biomedicina i zdravstvo, biotehničko područje)

POVEZANOST RADA