|
|
ANALYSIS OF NON-ENZYMATIC POSTTRANSLATIONAL MODIFICATED (GLYCATED) ALBUMIN BY NANO-LC/MS/MS
Šťastná, Zdeňka ; Pataridis, Statis ; Sedláková, Pavla ; Mikšík, Ivan
Posttranslational modifications of proteins are important reactions, which significantly affect the function of proteins in the organism. In principle, they can be divided into enzymatic and non-enzymatic modifications. Non-enzymatic reactions include glycation (earlier called nonezymatic glycosylation), which plays an important role in the development of chronic complications of diabetes mellitus, uremia, in the process of aging and degeneration of the brain.This work deals with the study of glycated albumins (human serum albumin and bovine serum albumin). Methodologically we used nano-liquid chromatography coupled to Q-TOF mass spectrometer. In vitro modified proteins were cleavaged by trypsin and arising peptides were separated on C18 nano column with trap-column. Peptides and their modifications were analysed by high-resolution Q-TOF mass spectrometer MaXis with precision determination of mass below 2 ppm. We found some modifications of proteins. Besides well known carboxymethyllysine new ones were determined - create mass shift 78, 132 and 218. Origin of these modifications is discussed and possible structure is presented. All found modifications were allocated to the structure of proteins and reactivity to various oxo-compounds was also examined
|
|
| |
|
|
Chiral analysis of beta-alanyl-D,L-tyrosine and its derivatives by capillary electrophoresis with 2-hydroxypropyl-beta-cyclodextrin stereoselector
Sázelová, Petra ; Šolínová, Veronika ; Schimperková, Tereza ; Mášová, Alice ; Jiráček, Jiří ; Kašička, Václav
A new capillary electrophoretic method was developed for separation of enantiomers of antimicrobial dipeptide betha-Ala-D,L-Tyr and its derivatives using 50 mM Tris-phosphate, pH 2.50, as background electrolyte and 2-hydroxypropyl-betha-cyclodextrin at concentrations 20 – 60 mg/mL as chiral selector. In addition, association constants of complexes of the enatiomers of dipeptide betha-Ala-D,L-Tyr and its derivatives with 2-hydroxypropyl-betha-cyclodextrin chiral selector were determined.
|
|
|
Capillary electrophoretic chiral analysis and estimation of helix inversion barrier of helquats using randomly sulfated cyclodextrins as chiral selectors
Kašička, Václav ; Koval, Dušan ; Sázelová, Petra ; Severa, Lukáš ; Adriaenssens, Louis ; Vávra, Jan ; Teplý, Filip
Capillary electrophoresis in acidic sodium phosphate background electrolyte, pH 2.4, with randomly sulfated alpha-, beta- and gamma-cyclodextrins as chiral selectors was employed for fast, high-resolution separation of enantiomers of a series of 24 helquats, a new class of N-heteroaromatic dicationic helicene-like species. The developed CE methodology will be utilized in the further investigation of helquats, e.g., in evaluation of their preparative enantioresolution procedures, in monitoring of their racemization and determination of interconversion barrier of helquat enantiomers.
|
|
|
Analysis of antimicrobial peptides by capillary electrophoresis
Ehala, Sille ; Niederhafner, Petr ; Čeřovský, Václav ; Řezanka, P. ; Sýkora, D. ; Král, V. ; Kašička, Václav
Capillary electrophoresis was used for the purity degree determination of new antimicrobial peptides: octadecapeptide melectin and tetradecapeptide mastoparan PDD-B, and their synthetic analogues. Besides, four semiempirical models correlating electrophoretic mobilities of these peptides with their charge and size (relative molecular mass) were applied to predict their probable structures in solution. Additionally, capillaries coated with gold nanoparticles were employed for the separation of mixtures of antimicrobial peptides.
|
|
|
Capillary electrophoresis applied to analysis and characterization of mono-N-acyl-2,6-diaminopimelic acid derivatives
Vítovcová, M. ; Hlaváček, Jan ; Pícha, Jan ; Vaněk, Václav ; Jiráček, Jiří ; Kašička, Václav
Capillary zone electrophoresis and micellar electrokinetic chromatography have been employed for determination of electrophoretic purity degree, limit of detection and limit of quantification of twelve mono-Nacylated derivatives of 2,6-diaminopimelic acid (DAP). In addition, the DAP derivatives were characterized by effective electrophoretic mobilities of their cationic and anionic forms in several classical and isoelectric buffer-based background electrolytes within a broad pH range 2.18 – 8.64.
|
|
| |
|
| |
|
|
Enantiomer separation and determination of helix inversion barrier of helical dications by capillary electrophoresis
Koval, Dušan ; Adriaenssens, Louis ; Severa, Lukáš ; Teplý, Filip ; Sázelová, Petra ; Kašička, Václav
Enantiomeric helical forms of dicationic helquats, a novel family of charged helicene-like molecules, have been separated by capillary electrophoresis (CE) using sodium-phosphate buffer, pH 2.5, as background electrolyte and sulfated beta- and gamma-cyclodextrins as chiral selectors. Additionally, CE was used to determine barrier to helix inversion of helquats.
|
|
| |
guest ::
