Search results

1

Binding of human plasminogen and high-molecular-mass kininogen by cell surface-exposed proteins of Candida parapsilosis

100%

Karkowska-Kuleta J., Zajac D., Bras G., Bochenska O., Rapala-Kozik M., Kozik A.

|

2017

|

vol. 64

|

issue 3

391-400

EN

Pathogenic microbes can recruit to their cell surface human proteins that are components of important proteolytic cascades involved in coagulation, fibrinolysis and innate immune response. Once located at the bacterial or fungal surface, such deployed proteins might be utilized by pathogens to facilitate invasion and dissemination within the host organism by interfering with functionality of these systems or by exploiting specific activity of the bound enzymes. Aim of the study presented here was to characterize this phenomenon in Candida parapsilosis (Ashford) Langeron et Talice - an important causative agent of systemic fungal infections (candidiases and candidemias) in humans. We have investigated the interactions of fungal surface-exposed proteins with plasminogen (HPG) and high-molecular-mass kininogen (HK) - the crucial components of human fibrinolytic system and proinflammatory/procoagulant contact-activated kinin-forming system, respectively. After confirming ability of the fungal surface-exposed proteins to bind HPG and HK, four of them - two agglutinin-like sequence (Als) proteins CPAR2_404780 and CPAR2_404800, a heat shock protein Ssa2 and a moonlighting protein 6-phosphogluconate dehydrogenase 1 - were purified using ion-exchange chromatography, gel filtration and chromatofocusing. Then, their affinities to HPG and HK were characterized with surface plasmon resonance measurements. The determined dissociation constants for the investigated protein-protein complexes were within a 10-7 M order for the HPG binding and in a range of 10-8-10-9 M for the HK binding. Detailed characterization of adsorption of these two important plasma proteins on the fungal cell surface may help to increase our understanding of molecular mechanisms of C. parapsilosis-dependent candidiasis.

2

Kinetic and thermodynamic characterization of the interactions between the components of human plasma kinin-forming system and isolated and purified cell wall proteins of Candida albicans

100%

Seweryn K., Karkowska-Kuleta J., Wolak N., Bochenska O., Kedracka-Krok S., Kozik A., Rapala-Kozik M.

|

2015

|

vol. 62

|

issue 4

825-835

EN

Cell wall proteins of Candida albicans, besides their best known role in the adhesion of this fungal pathogen to host's tissues, also bind some soluble proteins, present in body fluids and involved in maintaining the biochemical homeostasis of the human organism. In particular, three plasma factors - high-molecular-mass kininogen (HK), factor XII (FXII) and prekallikrein (PPK) - have been shown to adhere to candidal cells. These proteins are involved in the surface-contact-catalyzed production of bradykinin-related peptides (kinins) that contribute to inflammatory states associated with microbial infections. We recently identified several proteins, associated with the candidal cell walls, and probably involved in the binding of HK. In our present study, a list of potential FXII- and PPK-binding proteins was proposed, using an affinity selection (on agarose-coupled FXII or PPK) from a whole mixture of β-1,3-glucanase-extrated cell wall-associated proteins and the mass-spectrometry protein identification. Five of these fungal proteins, including agglutinin-like sequence protein 3 (Als3), triosephosphate isomerase 1 (Tpi1), enolase 1 (Eno1), phosphoglycerate mutase 1 (Gpm1) and glucose-6-phosphate isomerase 1 (Gpi1), were purified and characterized in terms of affinities to the human contact factors, using the surface plasmon resonance measurements. Except Gpm1 that bound only PPK, and Als3 that exhibited an affinity to HK and FXII, the other isolated proteins interacted with all three contact factors. The determined dissociation constants for the identified protein complexes were of 10-7 M order, and the association rate constants were in a range of 104-105 M-1s-1. The identified fungal pathogen-host protein interactions are potential targets for novel anticandidal therapeutic approaches.

3

Characterization of the interactions between human high-molecular-mass kininogen and cell wall proteins of pathogenic yeasts Candida tropicalis

75%

Karkowska-Kuleta J., Zajac D., Bras G., Bochenska O., Seweryn K., Kedracka-Krok S., Jankowska U., Rapala-Kozik M., Kozik A.

|

2016

|

vol. 63

|

issue 3

427-436

EN

Candida tropicalis is one of the most frequent causes of serious disseminated candidiasis in human patients infected by non-albicans Candida species, but still relatively little is known about its virulence mechanisms. In our current study, the interactions between the cell surface of this species and a multifunctional human protein - high-molecular-mass kininogen (HK), an important component of the plasma contact system involved in the development of the inflammatory state - were characterized at the molecular level. The quick release of biologically active kinins from candidal cell wall-adsorbed HK was presented and the HK-binding ability was assigned to several cell wall-associated proteins. The predicted hyphally regulated cell wall protein (Hyr) and some housekeeping enzymes exposed at the cell surface (known as "moonlighting proteins") were found to be the major HK binders. Accordingly, after purification of selected proteins, the dissociation constants of the complexes of HK with Hyr, enolase, and phosphoglycerate mutase were determined using surface plasmon resonance measurements, yielding the values of 2.20 × 10-7 M, 1.42 × 10-7 M, and 5.81 × 10-7 M, respectively. Therefore, in this work, for the first time, the interactions between C. tropicalis cell wall proteins and HK were characterized in molecular terms. Our findings may be useful for designing more effective prevention and treatment approaches against infections caused by this dangerous fungal pathogen.

Refine search results

3 Acta Biochimica Polonica

1 2017

1 2016

1 2015

3 Bochenska O.

3 Karkowska-Kuleta J.

3 Kozik A.

3 Rapala-Kozik M.

2 Bras G.

2 Kedracka-Krok S.

2 Seweryn K.

2 Zajac D.

1 Jankowska U.

1 Wolak N.

Binding of human plasminogen and high-molecular-mass kininogen by cell surface-exposed proteins of Candida parapsilosis

Kinetic and thermodynamic characterization of the interactions between the components of human plasma kinin-forming system and isolated and purified cell wall proteins of Candida albicans

Characterization of the interactions between human high-molecular-mass kininogen and cell wall proteins of pathogenic yeasts Candida tropicalis