scholarly journals Preliminary Studies on the Mucus Secretion of the Wood Wasp, Sirex Noctilio F. I. Physicochemical and Biochemical Properties

1976 ◽  
Vol 29 (2) ◽  
pp. 21 ◽  
Author(s):  
LK Wong ◽  
RK Crowden
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Enzyme Activities ◽  
Proteolytic Enzyme ◽  
Physiological Activity ◽  
Biochemical Properties ◽  
Mucus Secretion ◽  
Sirex Noctilio ◽  
Polysaccharide Complex

The major component of S. noctilio mucus appears to be a protein-polysaccharide complex with probable molecular weight in the range 60000-100000. In aqueous solution the macromolecule undergoes slow spontaneous disaggregation to yield dialysable subunits of molecular weight 2000-6000 which retain all the physiological activity of the whole mucus. More rapid disaggregation is brought about by treatment of solutions with moderate concentrations of NaC!, KCI or CaCI2 , or by heating. The native mucus contains amylase, esterase, phenoloxidase and proteolytic enzyme activities, and it is suggested that these enzymes may be responsible, at least in part, for the 'natural' disaggregation process.

Preparation and Properties of Human Prothrombin Complex

1970 ◽  
Vol 24 (03/04) ◽  
pp. 325-333 ◽  
Author(s):  
G. H Tishkoff ◽  
L. C Williams ◽  
D. M Brown
Keyword(s):  
Molecular Weight ◽  
Proteolytic Enzyme ◽  
Enzyme Inhibitor ◽  
Specific Activity ◽  
Crystalline Form ◽  
Sedimentation Equilibrium ◽  
Crystalline Complex ◽  
Interaction Product ◽  
Proteolytic Enzyme Inhibitor ◽  
Purification Scheme

SummaryAs a corollary to our previous studies with bovine prothrombin, we have initiated a study of human prothrombin complex. This product has been isolated in crystalline form as a barium glycoprotein interaction product. Product yields were reduced compared to bovine product due to the increased solubility of the barium glycoprotein interaction product. On occasion the crystalline complex exhibited good yields. The specific activity of the crystalline complex was 1851 Iowa u/mg. Further purification of human prothrombin complex was made by removal of barium and by chromatography on Sephadex G-100 gels. The final product evidenced multiple procoagulant activities (II, VII, IX and X). The monomeric molecular weight determined by sedimentation equilibrium in a solvent of 6 M guanidine-HCl and 0.5% mercaptoethanol was 70,191 ± 3,057 and was homogeneous with respect to molecular weight. This product was characterized in regard to physical constants and chemical composition. In general, the molecular properties of human prothrombin complex are very similar to the comparable bovine product. In some preparations a reversible proteolytic enzyme inhibitor (p-aminophenylarsonic acid) was employed in the ultrafiltration step of the purification scheme to inhibit protein degradation.

Heterogeneity of High-molecular-weight Human Salivary Mucins

2000 ◽  
Vol 14 (1) ◽  
pp. 69-75 ◽  
Author(s):  
G.D. Offner ◽  
R.F. Troxler
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Biochemical Properties ◽  
Salivary Proteins ◽  
Molecular Weights ◽  
Structural Framework ◽  
Buccal Epithelial Cells ◽  
Membrane Bound ◽  
Membrane Spanning ◽  
Micro Organisms

The existence of high-molecular-weight glycoproteins in saliva and salivary secretions has been recognized for nearly 30 years. These proteins, called mucins, are essential for oral health and perform many diverse functions in the oral cavity. Mucins have been intensively studied, and much has been learned about their biochemical properties and their interactions with oral micro-organisms and other salivary proteins. In the past several years, the major high-molecular-weight mucin in salivary secretions has been identified as MUC5B, one of a family of 11 human mucin gene products expressed in tissue-specific patterns in the gastrointestinal, respiratory, and reproductive tracts. MUC5B is one of four gel-forming mucins which exist as multimeric proteins with molecular weights greater than 20-40 million daltons. The heavily glycosylated mucin multimers form viscous layers which protect underlying epithelial surfaces from microbial, mechanical, and chemical assault. Another class of mucin molecules, the membrane-bound mucins, is structurally and functionally distinct from the gel-forming mucins. These proteins do not form multimers and can exist as both secreted and membrane-bound forms, with the latter anchored to epithelial cell membranes through a short membrane-spanning domain. In the present work, we show that two of the membrane-bound mucins, MUC1 and MUC4, are expressed in all major human salivary glands as well as in buccal epithelial cells. While the functions of these mucins in the oral environment are not understood, it is possible that they form a structural framework on the cell surface which not only is cytoprotective, but also may serve as a scaffold upon which MUC5B, and possibly other salivary proteins, assemble.

scholarly journals Purification of acrylamide from polymerization inhibitors in the manufacture of high quality flocculants based on polyacrylamide

2020 ◽  
Vol 3 (2) ◽  
pp. 109-113
Author(s):  
V. P. Duleba ◽  
◽  
Z. Ya. Hnativ ◽  
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Polymerization Process ◽  
Iron Ions ◽  
Laboratory Studies ◽  
Catalytic Method ◽  
High Quality ◽  
Variable Valence ◽  
Sulfuric Acid Method ◽  
Practical Information

Polyacrylamide and its copolymers are widely used as flocculating agents for the separation of industrial suspensions. The formation of high molecular weight polymers depends on the content of various impurities present in the monomer. The article presents the scientific and practical information on the production of acrylamide by sulfuric acid method of hydration of nitrile acrylic acid in the form of an aqueous solution of different concentrations and a more modern heterogeneously catalytic method of hydration of acrylonitrile using as catalysts with variable valence. Ways to get different impurities in the stages of production of acrylamide with the purpose of applying appropriate methods for its purification. Laboratory studies of the purification of an aqueous solution of acrylamide from iron ions were carried out as an element of inhibition of the premature polymerization process.

High molecular weight polypeptides related to dynein heavy chains in Nicotiana tabacum pollen tubes

1995 ◽  
Vol 108 (3) ◽  
pp. 1117-1125
Author(s):  
A. Moscatelli ◽  
C. Del Casino ◽  
L. Lozzi ◽  
G. Cai ◽  
M. Scali ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Nicotiana Tabacum ◽  
Pollen Tube ◽  
High Molecular Weight ◽  
Pollen Tubes ◽  
Biochemical Properties ◽  
Bovine Brain ◽  
Atp Binding ◽  
Heavy Chains ◽  
Dynein Heavy Chains

Nicotiana tabacum pollen tubes contain two high molecular weight polypeptides (about 400 kDa), which are specifically expressed during pollen germination and pollen tube growth in BK medium. The high molecular weight doublet resembles the dynein heavy chains in some biochemical properties. Sedimentation profiles of pollen tube extracts show that the high molecular weight bands have sedimentation coefficients of 22 S and 12 S, respectively. ATPase assay of sedimentation fractions shows an activity ten times higher when stimulated by the presence of bovine brain microtubules in fractions containing the 22 S high molecular weight polypeptide. Both these high molecular weight polypeptides can bind microtubules in an ATP-dependent fashion. A mouse antiserum to a synthetic peptide reproducing the sequence of the most conserved ATP-binding site among dynein heavy chains recognized the two high molecular weight polypeptides. Therefore these polypeptides have sequences immunologically related to the ATP binding sites of dynein heavy chains.

Screening of fibrolytic enzymes as additives for ruminant diets: relationship between enzyme activities and the in vitro degradation of enzyme-treated forages

2002 ◽  
Vol 2002 ◽  
pp. 210-210 ◽  
Author(s):  
D. Colombatto ◽  
D.P. Morgavi ◽  
A.F. Furtado ◽  
K.A. Beauchemin
Keyword(s):  
Enzyme Activities ◽  
Biochemical Properties ◽  
Ruminal Fermentation ◽  
Maize Silage ◽  
In Vitro Degradation ◽  
Enzyme Preparations ◽  
Commercial Enzyme ◽  
Ruminant Diets ◽  
Feed Enzymes

Results in the literature concerning the efficacy of feed enzymes for ruminant diets have been mixed. Commercial preparations currently used are fermentation extracts containing several enzymic activities. It has been suggested that ruminal fermentation of grass and maize silages is enzyme-limited (Wallace et al., 2001). In order to design better enzyme additives, the enzyme activities likely to affect the animal responses should be identified. This study examined 23 commercial enzyme preparations for their biochemical properties and their ability to influence the in vitro degradation of alfalfa and maize silage.

scholarly journals Low Molecular Weight Gelators Based on Functionalized l-Dopa Promote Organogels Formation

Gels ◽  
2019 ◽  
Vol 5 (2) ◽  
pp. 27 ◽  
Author(s):  
Demetra Giuri ◽  
Nicola Zanna ◽  
Claudia Tomasini
Keyword(s):  
Aqueous Solution ◽  
Molecular Weight ◽  
Rheological Properties ◽  
Rhodamine B ◽  
Lauric Acid ◽  
Water Solution ◽  
Preliminary Test ◽  
Low Molecular Weight ◽  
Coupling Reactions ◽  
Low Molecular Weight Gelators

We prepared the small pseudopeptide Lau-l-Dopa(OBn)2-d-Oxd-OBn (Lau = lauric acid; l-Dopa = l-3,4-dihydroxyphenylalanine; d-Oxd = (4R,5S)-4-methyl-5-carboxyl-oxazolidin-2-one; Bn = benzyl) through a number of coupling reactions between lauric acid, protected l-Dopa and d-Oxd with an excellent overall yield. The ability of the product to form supramolecular organogels has been tested with different organic solvents of increasing polarity and compared with the results obtained with the small pseudopeptide Fmoc-l-Dopa(OBn)2-d-Oxd-OBn. The mechanical and rheological properties of the organogels demonstrated solvent-dependent properties, with a storage modulus of 82 kPa for the ethanol organogel. Finally, to have a preliminary test of the organogels’ ability to adsorb pollutants, we treated a sample of the ethanol organogel with an aqueous solution of Rhodamine B (RhB) for 24 h. The water solution slowly lost its pink color, which became trapped in the organogel.

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