Hydroxyurea was administered intraperitoneally to pregnant albino rats in a single dose of 2000 mg/kg on day 14 of gestation. Both the perinatal and postnatal mortality rates of the progeny were increased and their weight gain reduced. Exploratory locomotion of 32-day-old rats, calculated by means of an 'activity index', was significantly reduced. The treatment had no effect on the brain weight. The fertility of the progeny was not impaired.

Animals↗

PubMed1980

Isolation and characterization of human urinary kallikrein.

Human urinary kallikrein was purified by gel filtration on Sephacryl S-200 and affinity chromatography on aprotinin-Sepharose, followed by ion exchange chromatography on DEAE-Sepharose. Thus an enzyme preparation with a specific activity (using AcPheArgOEt as substrate) of 1 100 U/mg protein was obtained. A specific bioligical activity of 2 300 KE/mg was measured in the dog blood pressure assay and of 0.742 HMW kininogen-U/mg, corresponding to the liberation of 787 micrograms bradykinin per mg enzyme per min from HMW-kininogen, in the rat uterus assay. In dodecyl sulfate electrophoresis two protein bands with apparent molecular weights of 41 000 and 34 000 were separated. The amino acid composition was determined and isoleucine was identified as the only aminoterminal amino acid. On isoelectric focusing six protein bands with isoelectric points of 3.75, 3.80, 3.90, 4.00, 4.05 and 4.25 were separated. The kinetic constants for the kallikrein-catalyzed hyrdolysis of AcPheArgOEt and D ValLeuArgNHNp were determined. The bimolecular velocity constant for the inhibition by diisopropyl fluorophosphate was determined as 9 +/- 2l x mol-1 x min-1. Immunological studies showed that a close relationship exists between the urinary enzyme and other human glandular kallikreins. Deoxycholate, lysolecithin and other amphiphiles activated human urinary kallikrein.

Amino Acids↗

PubMed1980

Oligomerisation of boar acrosin.

Boar acrosin, a glycoprotein present in the acrosome of spermatozoa, tends to aggregate in the absence of detergents and lipids. Self-association products were analyzed electrophoretically by the method of Ferguson. Molecular weights ranging from 44 000 up to 237 000 were found, corresponding to acrosin monomer up to hexamer. Involvement of the active site of the serine proteinase in the formation of oligomers was demonstrated by active enzyme staining and determination of amidase activity of aggregated acrosin. Only monomeric acrosin proved to have full activity, while a marked decrease in specific activity was found upon aggregation. Hence, evidence is presented that acrosin has hydrophobic binding sites modulating the proteinase activity.

Acrosin↗

PubMed1980

Interactions of boar acrosin with detergents.

The activity of boar acrosin was found to be stimulated up to 260% by non-ionic detergents if present in concentrations above their critical micelle concentration. In addition, the stability of acrosin was remarkably enhanced in the presence of 0.1% (w/v) detergents. Triton X-100 was found to reduce the affinity of acrosin to the synthetic inhibitor 6-amidino-2(4'-methoxyphenyl)indole by the factor 2.9 when Ki values were measured in buffer solutions in the presence (0.1%, w/v) and absence of Triton X-100. Phospholipids did nearly completely abolish the acrosin activity, this effect being reversibly by addition of 0.1% (w/v) Triton X-100. These results are interpreted in terms of hydrophobic binding sites exposed on the surface of the acrosin molecule. Hence, for the first time data are presented characterizing acrosin as a membrane-associated protein.

Acrosin↗

PubMed1980

Isolation of an enzymatically active glandular kallikrein from human plasma by immunoaffinity chromatography.

A glandular kallikrein from human plasma was isolated by immunoaffinity chromatography and characterized. The molecular weight was determined to 40,000 by gel filtration. The enzyme preparation liberates kinins from human HMW kininogen (specific activity: 0.328 HMW kininogen-U/A280 unit), lowers the blood pressure of dogs after intravenous injection (specific activity: 1090 KE/A280 unit), is inhibited by diisopropyl fluorophosphate and aprotinin, but not by SBTI. In the radioimmunoassay for human urinary kallikrein parallel binding curves were obtained. AcPheArgOEt, DVal-LeuArgOEt and ZTyrONp are cleaved with identical rates by the kallikrein preparation and human urinary kallikrein.

Chromatography, Affinity↗

PubMed1980

Purification and properties of boar acrosin.

An isolation procedure in the presence of non-ionic detergents has been developed for the large-scale preparation of boar acrosin. Five steps including hydrophobic interaction chromatography on phenyl-Sepharose resulted in a 161-fold purification of the enzyme with an accumulation yield of 41%. The resultant acrosin preparation had a molecular weight of 38,000, an isoelectric point of 10.5 and a specific activity of 37 U/mg. Apparent homogeneity was judged by sodium dodecyl sulfate electrophoresis and isoelectric focusing. A polarity index of 41.2% was calculated from the amino acid composition. Acrosin was stable at pH 5.5 in the presence of 0.1% Triton X-100. In the absence of detergent acrosin was strongly adsorbed on plastic surfaces.

Acrosin↗

PubMed1980

N-Terminal amino acid sequence of boar sperm acrosin. Homology with other serine proteinases.

Boar acrosin with a molecular weight of 38,000 had been isolated. An N-terminal amino acid sequence of 52 residues was determined on the S-carboxymethylated material. The protein contains a single peptide chain. Up to 48% of the positions in the sequence show identity with those of some serine proteinases. The highest degree of homology was found at the comparison with plasmin and chymotrypsin. The N-terminus of acrosin corresponds to that of a serine proteinase in the activated form. The N-terminal amino acid is valine.

Acrosin↗

PubMed1980

Papulacandins, a new family of antibiotics with antifungal activity. Structures of papulacandins A, B, C and D.

The structures of the papulacandins A, B, C and D, new antibiotics of Papularia sphaerosperma have been established by means of spectral analysis and degradation reactions. Base catalysed hydrolysis of the main product papulacandin B (1) gave two new hydroxylated long-chain unsaturated fatty acids 5 and 6 along with a hitherto unknown spirocyclic diglycoside 7. The structure of 7 was determined by further degradation reactions. The positions of attachment of the two fatty acids to the spirocyclic diglycoside 7 through ester-bonds were established by selective base catalysed hydrolysis of 1 and spectral analysis of 1 and some derivatives and degradation products thereof. The structures of papulacandin A (2), papulacandin C (3) and papulacandin D (4) were determined in an analogous way.

Aminoglycosides↗

PubMed1980

Structure of the elastase-cathepsin G inhibitor of the leech Hirudo medicinalis.

The leech Hirudo medicinalis contains three different groups of proteinase inhibitor proteins, the thrombin-specific hirudin, the bdellins directed against trypsin, plasmin and acrosin, and the eglins which were discovered only recently. We are interested in the eglins mainly for two reasons: (i) They form strong complexes with the granulocytic elastase and cathepsin G with Ki values close to 1 x 10(-10) mol/l. Due to this property they are potential candidates for the therapeutic treatment of various diseases. (ii) Although the eglins do not contain a disulfide bridge to stabilize the tertiary structure, they are highly resistant to denaturation by acidification and by heat as well as to proteolytic degradation.

Amino Acid Sequence↗

PubMed1979

[Clinical diagnosis of bacteriuria].

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Bacteriuria↗

PubMed1979

[Coagulase negative Staphylococcus in the urine].

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Bacteriuria↗