An Efficient Synthesis of the Pentasaccharide Repeating Unit of Pseudomonas Aeruginosa Psl Exopolysaccharide for Lectin-Binding Studies

PS2 Poster session 2 Even numbers
Location (hall): 
Start/end time: 
Tuesday, July 2, 2019 - 15:45 to 17:15

Fruzsina Demeter1, Anikó Borbás1, Mihály Herczeg1,2

1University Of Debrecen, Department of Pharmaceutical Chemistry, Debrecen, Hungary, 2Research Group of Oligosaccharide Chemistry of Hungarian Academy of Sciences, Debrecen, Hungary

Pseudomonas aeruginosa is an opportunistic Gram-negative bacteria, which is the main cause of hospital associated infections, for example in the case of chronic lung injury or cystic fibrosis. Among the bacterial pathogens tested, this bacterium has the highest genom coding capacity and regulatory network density, which allows the bacterium to defer and survive in a variety of environmental conditions [1]. All of these factors and the aggressive use of antibiotics in the recent years have led to serious drug resistance in the investigated pathogen. Therefore it is time to search and apply new approaches to the prevention and treatment of these infections. Taiwanese researchers have observed that the recombinant horseshoe crab plasma lectin (rHPL, rhamnose binding lectin [2]) is able to inhibit the bacteria in forming the biofilm layer which is used for protection, owing to the fact that more components of the biofilm layer contain rhamnose units (eg lipopolysaccharides, Psl polysaccharide or dirhamnolipids). From these, Psl [1] is an exopolysaccharide containing repeating pentaccharide moieties, which plays particularly important role in the formation and maintenance of the biofilm.

Our research group has been involved in the synthesis of biologically active oligosaccharides for decades [3], [4], [5]. The aim of our current co-operation is to more accurately identify the interaction between the pentasaccharide part of the Psl exopolysaccharide and the rHPL lectin. Within this research, our goal was to design and perform an efficient synthesis of the commercially not available pentasaccharide for the biological investigations. Herein, synthesis of the pentamer repeating unit as a p-methoxyphenyl glycoside (see Figure 1.) will be presented.

The structure of the target pentasaccharide


Supported by the ÚNKP New National Excellence Program of the Ministry of Human Capacities.

The authors gratefully acknowledge financial support for this research from the Premium Postdoctoral Program of HAS (PPD 461038) and from the EU and co-financed by the European Regional Development Fund under the project GINOP-2.3.2-15-2016-00008

  1. H. Li; K.-F. Mo; Q. Wang; C. K. Stover; A. DiGiandomenico; G.-J. Boons, Chem. Eur. J., 2013, 19, 17425–17431.
  2. S. T.;Chiou, Y. W. Chen, S. C. Chen, C. F. Chao, T. Y. Liu, J. Biol. Chem. 2000, 275, 1630-4.
  3. M. Herczeg, L. Lázár, A. Borbás, A. Lipták, S. Antus, Org. Lett., 2009, 11, 2619-2622.
  4. M. Herczeg, L. Lázár, Zs. Bereczky, K. E. Kövér, I. Timári, J. Kappelmayer, A. Lipták, S. Antus, A. Borbás, Chem. Eur J. 2012, 18, (34), 10643-10652.
  5. M. Herczeg, E. Mező, N. Molnár, S.-K. Ng, Y.-C. Lee, M. D.-T. Chang, A. Borbás, Chem. Asian J., 2016, 11, (23), 3398-3413.