The cercarial glycocalyx of Schistosoma mansoni.

Cercariae, the freshwater stage of Schistosoma mansoni infectious to man, are covered by a single unit membrane and an immunogenic glycocalyx. When cercariae penetrate the host skin, they transform to schistosomula by shedding tails, secreting mucous and enzymes, and forming microvilli over their surface. Here the loss of the glycocalyx from cercariae transforming in vitro was studied morphologically and biochemically. By scanning electron microscopy, the glycocalyx was a dense mesh composed of 15-30 nm fibrils that obscured spines on the cercarial surface. The glycocalyx was absent on organisms fixed without osmium and was partially lost when parasites aggregated in their own secretions before fixation. By transmission electron microscopy, a 1-2 microns thick mesh of 8-15-nm fibrils was seen on parasites incubated with anti-schistosomal antibodies or fixed in aldehydes containing tannic acid or ruthenium red. Cercariae transformed to schistosomula when tails were removed mechanically and parasites were incubated in saline. Within 5 min of transformation, organisms synchronously formed microvilli which elongated to 3-5 microns by 20 min and then were shed. However, considerable fibrillar material remained adherent to the double unit membrane surface of schistosomula. For biochemical labeling, parasites were treated with eserine sulfate, which blocked cercarial swimming, secretion, infectivity, and transformation to schistosomula. Material labeled by periodate oxidation and NaB3H4 was on the surface as shown by autoradiography and had an apparent molecular weight of greater than 10(6) by chromatography. Periodate-NaB3H4 glycocalyx had an isoelectric point of 5.0 +/- 0.4 and was precipitable with anti-schistosomal antibodies. More than 60% of the radiolabeled glycocalyx was released into the medium by transforming parasites in 3 h and was recovered as high molecular weight material. Parasites labeled with periodate and fluorescein-thiosemicarbazide and then transformed had a corona of fluorescence containing microvilli, much of which was shed onto the slide. Material on cercariae labeled by lodogen-catalyzed iodination was also of high molecular weight and was antigenic. In conclusion, the cercarial glycocalyx appears to be composed of acidic high molecular weight fibrils which are antigenic and incompletely cleared during transformation.

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Expression of high molecular weight tau in the central and peripheral nervous systems

Journal of Cell Science ◽

10.1242/jcs.105.3.729 ◽

1993 ◽

Vol 105 (3) ◽

pp. 729-737

Author(s):

I.S. Georgieff ◽

R.K. Liem ◽

D. Couchie ◽

C. Mavilia ◽

J. Nunez ◽

...

Keyword(s):

Spinal Cord ◽

Molecular Weight ◽

Nervous System ◽

High Molecular Weight ◽

Tumor Cells ◽

Apparent Molecular Weight ◽

In Vitro Transcription ◽

The Central Nervous System ◽

Immunohistochemical Studies

Using a novel PCR approach, we have cloned a cDNA encoding the entire high molecular weight tau molecule from rat dorsal root ganglia. The resulting 2080 bp cDNA differs from low molecular weight rat brain tau by the insertion of a novel 762 bp region (exon 4a) between exons 4 and 5. This cDNA clone is identical in sequence with a high molecular weight tau (HMW) cDNA from rat PC12 tumor cells and is closely related to a HMW tau cDNA from mouse N115 tumor cells. In vitro transcription/translation produces a protein that migrates on SDS-PAGE with the same apparent molecular weight as HMW tau purified from rat sciatic nerve. The HMW tau protein is generated from an 8 kb mRNA, which can be detected by northern blots in peripheral ganglia, but not in brain. A more sensitive assay using PCR and Southern blot analysis demonstrates the presence of exon 4a in spinal cord and in retina. In combination with immunohistochemical studies of spinal cord, these data suggest that HMW tau, though primarily in the peripheral nervous system, is also expressed in limited areas of the central nervous system, although its presence cannot be detected in the cerebral cortices.

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Terminal sequence studies of high-molecular-weight ribonucleic acid. The 3′-termini of rabbit globin messenger ribonucleic acid

Biochemical Journal ◽

10.1042/bj1310315 ◽

1973 ◽

Vol 131 (2) ◽

pp. 315-325 ◽

Cited By ~ 13

Author(s):

J. A. Hunt

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Ribonucleic Acid ◽

Periodate Oxidation ◽

Apparent Molecular Weight ◽

Paper Electrophoresis ◽

Terminal Sequence ◽

Globin Mrna ◽

Messenger Ribonucleic Acid ◽

Oxidation Analysis

Haemoglobin mRNA isolated from EDTA-treated polyribosomes has an apparent molecular weight of 120000–180000 estimated by condensation with 3H-labelled isoniazid after periodate oxidation. Analysis of the ribonuclease digests of isoniazid-labelled RNA by paper electrophoresis and column chromatography enables the amount of contaminating 18S, 7S, 5S and 4S RNA to be estimated, and a corrected molecular weight of globin mRNA as the acid is 161000 or 500 nucleotides in length. This molecule contains two groups of 3′-terminal sequences in equal yield; G-Y-A6 and G-Y-A7 in the ratio 3:2, and G-N9–16-Y-A2 and G-N9–16-Y-N3 in the ratio 3:2. The significance of these sequences is discussed in relation to the poly(A) content of globin mRNA, the specificity of the sequences, and possible function in processing and biosynthesis of mRNA.

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The Effect of Dextran of Various Molecular Weight on the Coagulation in Dogs

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654535 ◽

1961 ◽

Vol 06 (01) ◽

pp. 015-024 ◽

Cited By ~ 32

Author(s):

Sven Erik Bergentz ◽

Oddvar Eiken ◽

Inga Marie Nilsson

Keyword(s):

Molecular Weight ◽

Body Weight ◽

High Molecular Weight ◽

Bleeding Time ◽

Factor Vii ◽

Low Molecular Weight ◽

Factor V ◽

Coagulation Mechanism ◽

Coagulation Defects

Summary1. Infusions of low molecular weight dextran (Mw = 42 000) to dogs in doses of 1—1.5 g per kg body weight did not produce any significant changes in the coagulation mechanism.2. Infusions of high molecular weight dextran (Mw = 1 000 000) to dogs in doses of 1—1.5 g per kg body weight produced severe defects in the coagulation mechanism, namely prolongation of bleeding time and coagulation time, thrombocytopenia, pathological prothrombin consumption, decrease of fibrinogen, prothrombin and factor VII, factor V and AHG.3. Heparin treatment of the dogs was found to prevent the decrease of fibrinogen, prothrombin and factor VII, and factor V otherwise occurring after injection of high molecular weight dextran. Thrombocytopenia was not prevented.4. In in vitro experiments an interaction between fibrinogen and dextran of high and low molecular weight was found to take place in systems comprising pure fibrinogen. No such interaction occurred in the presence of plasma.5. It is concluded that the coagulation defects induced by infusions of high molecular weight dextran are due to intravascular coagulation.

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Physicochemical and Antifungal Properties of Clotrimazole in Combination with High-Molecular Weight Chitosan as a Multifunctional Excipient

Marine Drugs ◽

10.3390/md18120591 ◽

2020 ◽

Vol 18 (12) ◽

pp. 591

Author(s):

Bożena Grimling ◽

Bożena Karolewicz ◽

Urszula Nawrot ◽

Katarzyna Włodarczyk ◽

Agata Górniak

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Weight Ratio ◽

Scanning Calorimetry ◽

Minimal Inhibitory Concentrations ◽

Dissolution Tests ◽

Effective Combination ◽

The Impact ◽

High Molecular Weight Chitosan

Chitosans represent a group of multifunctional drug excipients. Here, we aimed to estimate the impact of high-molecular weight chitosan on the physicochemical properties of clotrimazole–chitosan solid mixtures (CL–CH), prepared by grinding and kneading methods. We characterised these formulas by infrared spectroscopy, differential scanning calorimetry, and powder X-ray diffractometry, and performed in vitro clotrimazole dissolution tests. Additionally, we examined the antifungal activity of clotrimazole–chitosan mixtures against clinical Candida isolates under neutral and acid conditions. The synergistic effect of clotrimazole and chitosan S combinations was observed in tests carried out at pH 4 on Candida glabrata strains. The inhibition of C. glabrata growth reached at least 90%, regardless of the drug/excipient weight ratio, and even at half of the minimal inhibitory concentrations of clotrimazole. Our results demonstrate that clotrimazole and high-molecular weight chitosan could be an effective combination in a topical antifungal formulation, as chitosan acts synergistically with clotrimazole against non-albicans candida strains.

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Identity and Origin of the ATPase activity associated with neuronal microtubules. I. The ATPase activity is associated with membrane vesicles.

The Journal of Cell Biology ◽

10.1083/jcb.96.5.1298 ◽

1983 ◽

Vol 96 (5) ◽

pp. 1298-1305 ◽

Cited By ~ 13

Author(s):

D B Murphy ◽

R R Hiebsch ◽

K T Wallis

Keyword(s):

Molecular Weight ◽

Atpase Activity ◽

High Molecular Weight ◽

Brain Tissue ◽

Membrane Vesicles ◽

Microtubule Associated Proteins ◽

In Vitro Assembly ◽

Microtubule Protein ◽

Associated Proteins

Microtubule protein purified from brain tissue by cycles of in vitro assembly-disassembly contains ATPase activity that has been postulated to be associated with microtubule-associated proteins (MAPs) and therefore significant for studies of microtubule-dependent motility. In this paper we demonstrate that greater than 90% of the ATPase activity is particulate in nature and may be derived from contaminating membrane vesicles. We also show that the MAPs (MAP-1, MAP-2, and tau factors) and other high molecular weight polypeptides do not contain significant amounts of ATPase activity. These findings do not support the concept of "brain dynein" or of MAPs with ATPase activity.

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Interaction of Streptococcus mutans Glucosyltransferases with Teichoic Acids

Infection and Immunity ◽

10.1128/iai.29.2.376-382.1980 ◽

1980 ◽

Vol 29 (2) ◽

pp. 376-382

Author(s):

H. K. Kuramitsu ◽

L. Wondrack ◽

M. McGuinness

Keyword(s):

Molecular Weight ◽

High Molecular Weight ◽

Streptococcus Mutans ◽

Teichoic Acid ◽

Lipoteichoic Acid ◽

Water Soluble ◽

Heat Inactivation ◽

Teichoic Acids ◽

Insoluble Glucan

The Streptococcus mutans GS5 glucosyltransferase activities (both water-soluble and -insoluble glucan-synthesizing fractions) were inhibited by purified lipoteichoic acid. In vitro sucrose-dependent colonization of smooth surfaces by strain GS5 was also markedly reduced in the presence of the amphipathic molecules. The inhibition of soluble glucan synthesis by lipoteichoic acid appeared to be competitive with respect to both sucrose and primer dextran T10. These inhibitory effects were dependent on the presence of the fatty acid components of lipoteichoic acid since deacylated lipoteichoic acids did not inhibit glucosyltransferase activity. However, the deacylated molecules did interact with the enzymes since deacylated lipoteichoic acid partially protected the enzyme activity against heat inactivation and also induced the formation of high-molecular-weight enzyme complexes from the soluble glucan-synthesizing fraction. The presence of teichoic acid in high-molecular-weight aggregates of glucosyltransferase isolated from the culture fluids of strain GS5 was suggested by the detection of polyglycerophosphate in these fractions. In addition to strain GS5, two other organisms containing polyglycerophosphate teichoic acids, Lactobacillus casei and Lactobacillus fermentum , were demonstrated to bind glucosyltransferase activity. These results are discussed relative to the potential role of teichoic acid-glucosyltransferase interactions in enzyme binding to the cell surface of S. mutans and the formation of high-molecular-weight enzyme aggregates in the culture fluids of the organism.

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Processing of the precursor to a chloroplast ribosomal protein made in the cytosol occurs in two steps, one of which depends on a protein made in the chloroplast

Molecular and Cellular Biology ◽

10.1128/mcb.5.5.1093-1099.1985 ◽

1985 ◽

Vol 5 (5) ◽

pp. 1093-1099

Author(s):

R J Schmidt ◽

N W Gillham ◽

J E Boynton

Keyword(s):

Molecular Weight ◽

Protein Synthesis ◽

Ribosomal Protein ◽

Apparent Molecular Weight ◽

Protein L ◽

Mature Form ◽

Chloroplast Protein Synthesis ◽

Made In

In pulse-chase experiments in which log-phase cells of Chlamydomonas reinhardtii were labeled in vivo for 5 min with H2(35)SO4, fluorographs of immunoprecipitates from whole cell extracts revealed that chloroplast ribosomal proteins L-2, L-6, L-21, and L-29, which are made in the cytosol and imported, appeared in their mature forms. However, in the case of chloroplast ribosomal protein L-18, which is also made in the cytoplasm and imported, a prominent precursor with an apparent molecular weight of 17,000 was found at the end of a 5-min pulse. This precursor was processed to its mature size (apparent molecular weight of 15,500) within the first 5 min of the subsequent chase. As determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, the precursor to L-18 formed in vivo was 1.5 kilodaltons smaller than the primary product detected in translations of Chlamydomonas polyadenylated RNA in vitro. Upon a 10-min incubation with a postribosomal supernatant from Chlamydomonas, the 18,500-dalton precursor detected in vitro could be partially converted into a polypeptide that comigrated with the 17,000-dalton precursor detected in extracts of cells labeled in vivo. Under conditions in which the total amounts of chloroplast proteins had been reduced and cells were made to synthesize ribosomes rapidly, the apparent half-life of the 17,000-dalton precursor was extended over that seen in log-phase cells. When chloroplast protein synthesis was inhibited with lincomycin for 3 h before labeling under these conditions, the 17,000-dalton L-18 precursor but not the mature form was found, and the precursor was slowly degraded during a 60-min chase. When cells were placed in the dark for 3 h before labeling, processing of this precursor to the mature form appeared unaffected, but the chloroplast-synthesized ribosomal protein L-26 was detected, indicating that chloroplast protein synthesis was still occurring. We interpret these results to indicate that the maturation of protein L-18 in vivo involves at least two processing steps, one of which depends on a protein made on chloroplast ribosomes.

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Preparation of high-molecular weight and high-sulfate content chitosans and their potential antioxidant activity in vitro

Carbohydrate Polymers ◽

10.1016/j.carbpol.2005.04.007 ◽

2005 ◽

Vol 61 (2) ◽

pp. 148-154 ◽

Cited By ~ 97

Author(s):

Ronge Xing ◽

Song Liu ◽

Huahua Yu ◽

Zhanyong Guo ◽

Zhien Li ◽

...

Keyword(s):

Molecular Weight ◽

Antioxidant Activity ◽

High Molecular Weight ◽

Sulfate Content ◽

High Sulfate

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Pro-angiogenic effect of human kallikrein-related peptidase 12 (KLK12) in lung endothelial cells does not depend on kinin-mediated activation of B2 receptor

Biological Chemistry ◽

10.1515/hsz-2012-0291 ◽

2013 ◽

Vol 394 (3) ◽

pp. 385-391 ◽

Cited By ~ 11

Author(s):

Thomas Kryza ◽

Gilles Lalmanach ◽

Marion Lavergne ◽

Fabien Lecaille ◽

Pascale Reverdiau ◽

...

Keyword(s):

Molecular Weight ◽

Endothelial Cells ◽

High Molecular Weight ◽

High Molecular Weight Kininogen ◽

Kinin Receptor ◽

Angiogenic Effect ◽

Lung Endothelial Cells ◽

Carboxy Terminal

Abstract Kallikrein-12 (KLK12) may play an important role in angiogenesis modulating proangiogenic factor bioavailability and activating the kinin receptor B2 pathway. We studied whether KLK12 had an impact on angiogenesis and the activation of kinin receptor B2 results from the KLK12-dependent generation of kinins. KLK12 efficiently hydrolyzed high molecular weight kininogen, liberating a fragment containing the carboxy-terminal end of kinins. The kininogenase activity of KLK12 was poor, however, due to the cleavage resistance of the N-terminal side of the kinin sequence. A very low amount of kinins was accordingly released after in vitro incubation of high molecular weight kininogen with KLK12 and thus the proangiogenic activity of KLK12 in lung endothelial cells was not related to a kinin release.

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