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J Suttnar

Publications and source records attributed to J Suttnar.

45 records · Page 3Linked to original sources
PubMed1989

[The effect of blood platelet freezing on their antigen activity].

The authors investigated the effect of freezing of platelets after addition of various cryoprotective substances (glycerol, dimethyl sulphoxide and hydroxyethyl starch) on the preservation of some antigenic properties of these blood cells. It was revealed that during freezing of platelets in 5% glycerol and 4% hydroxyethyl starch no change of the specific antigen Kob and of HLA antigens occurred. Freezing in dimethylsulphoxide, however, weakened the activity of some antigens; usually this applied to antigen Kob, in HLA antigens it was rather an exception. From the results ensues, however, that in the transfusion practice it is important to foresee even in transfusions of cryopreserved platelets possible alloimmunization.

Antigens, Differentiation↗
PubMed1988

Evaluation of individual variability in the composition of Agkistrodon contortrix contortrix venom by means of HPLC and two-dimensional PAGE.

Qualitative and quantitative differences of coagulant enzymes in venom samples from individuals of the Agkistrodon c.c. were studied by means of 2D-PAGE and high performance anion-exchange chromatography. A great diversity was found among individual venoms. The two most similar venoms had an identical composition in only about 90%, the least similar ones in about 45% spots. All venoms studied contained more than two fractions with fibrinolytic activity. In three out of the nine analysed venoms two different thrombic proteases were present, one venom contained only one of these enzymes, whereas in five venoms no thrombic activity was detectable.

Animals↗
PubMed1988

Assessment of a complex mixture of interacting proteins in the coagulant active venom from Agkistrodon contortrix contortrix.

The crude venom of Agkistrodon contortrix contortrix was characterized by means of 2D-PAGE (using various separation principles in the respective directions) and high performance gel filtration chromatography. It was found that the venom presents a rich and remarkably stable mixture of proteins, mostly glycoproteins, which may interact each other. High stability of the venom in spite of the presence of many proteolytic enzymes, must most likely be attributed to the sugar moieties of venom proteins. Carbohydrate composition also causes considerable heterogeneity in charge and the presence of wide range of charge isomers. The intricate complexity of the venom makes it a real difficult-to-separate mixture.

Animals↗
PubMed1986

The reactivity of the disulfide bonds of human serum haemopexin.

The reactivity of the disulfide bonds of the specific haeme-binding plasma protein-human haemopexin has been studied with 2-mercaptoethanol. A molecule of haemopexin has six intrachain disulfide bridges (Takahashi et al., 1985) or which four are reactive while the remaining two can be reduced in the presence of greater than or equal to 4M urea. Disruption of the four reactive disulfide bonds in apohaemopexin abolishes the haeme binding ability. In equimolar haeme-haemopexin complex only one disulfide is reactive which suggests a large change in the tertiary structure of this protein on haeme binding.

Disulfides↗
PubMed1977

On the molecular conformation of human haemopexin. I. Reactivity of the tyrosine and tryptophan side chains.

The reactivity of the aromatic side chains of Tyr and Trp in human haemopexin were studied by chemical modifications and analysis of spectrophotometric titration curves. It has turned out that: 1. Under non-denaturing conditions the aromatic rings of Tyr resisted both acetylation and nitration. 2. Three indole groups of Trp reacted with the Koshland agent, without the native conformation of the protein being markedly affected (CD spectra). 3. Oxidation by N-bromosuccinimide split the peptide chain and the molecular conformation collapsed. 4. The Tyr residues could be placed into three classes, according to their pK values: 2 (or 1 in the haem-haemopexin complex) were normally accessible to titration, 5 were masked and the remaining 7 (or 8) were buried. 5. The spectrophotometric titration curve could not be analysed in terms of the Linderstrøm-Lang equation. The findings 1 to 3 refer to both haemopexin and its complex with haem; the spectrophotometric titration curves of the two molecules are very similar too. Consequently, the binding of haem is not associated with a profound alteration of the molecular architecture. The generally low reactivity of the side chains studied indicates that the hydrophobic peptide core of this glycoprotein is a compact one, very restricted in its contacts with the environment.

Circular Dichroism↗