scholarly journals The basal apparatus. Mass isolation from the molluscan ciliated gill epithelium and a preliminary characterization of striated rootlets.

1975 ◽  
Vol 64 (2) ◽  
pp. 408-420 ◽  
Author(s):  
R E Stephens
Keyword(s):  
Sodium Dodecylsulfate ◽  
Potassium Thiocyanate ◽  
Basal Bodies ◽  
Molecular Weights ◽  
Unique Protein ◽  
Structural Details ◽  
Basal Apparatus ◽  
Mass Isolation ◽  
Triton X

The basal apparatus, consisting of an array of interconnected basal bodies bearing bifurcating striated rootlets encompassing a nucleus, has been isolated from hypertonically deciliated columnar gill epithelial cells of the bay scallop Aequipecten irradians through gentle lysis with Triton X-100. The rootlets, 8-10 mum in length, were not easily preserved with conventional electron microscope fixatives, suggesting that the extent of their contribution to cellular architecture has been somewhat underestimated, even though Englemann described many of the structural details of the basal apparatus in 1880. The striated rootlets were soluble at high but not at low pH, in 2 M solutions of sodium azide and potassium thiocyanate but not sodium or potassium chloride, in 1% deoxycholate but not digitonin, and in the denaturing solvents 6 M guanidine-HC1, 8 M urea, and 1% sodium dodecylsulfate at 100 degrees C. The protein found consistently when rootlets were solubilized migrated on SDS-polyacrylamide gels as a closely spaced doublet with apparent molecular weights of 230,000 and 250,000 daltons. This unique protein, distinct from tropocollagen or various muscle components, has been named ankyrin because of the rootlet's anchor-like function in the cell.

Isolation of pure pellicles containing intact basal bodies of Tetrahymena pyriformis

1985 ◽  
Vol 77 (1) ◽  
pp. 155-165
Author(s):  
A. Tiedtke
Keyword(s):  
Pore Size ◽  
Tetrahymena Pyriformis ◽  
Basal Bodies ◽  
Electron Microscopic ◽  
Encapsulated Cells ◽  
Low Concentrations ◽  
Granular Matrix ◽  
Mass Isolation ◽  
Cytoskeletal Elements ◽  
Triton X

A new procedure for mass isolation of pure pellicles containing intact basal bodies of Tetrahymena pyriformis is reported. The success of the procedure depends on the elimination of the sticky mucocyst contents before fractionation of the cells, which is induced by Alcian Blue 8GS. Under appropriate ionic conditions greater than 95% of the cells are able to form a capsule by simultaneous extrusion of all mature mucocysts. About 50% of these cells are able to escape from their capsules, which are now devoid of mature mucocysts. These cells are separated from the empty capsules and encapsulated cells by passage through layers of gauze of 10 microns pore size. The fractionation of mucocyst-free cells in homogenization buffer yields pure pellicles, which are retained when the homogenate is sieved through steel sieves of 5 microns pore size. Electron-microscopic controls show that the isolated pellicles are not contaminated with subcellular particles. Cells homogenized in the presence of low concentrations of Triton X-100 yield pellicles consisting of the known cell-surface-associated cytoskeletal elements, together with basal bodies. The cilia are detached just above the kinetosomal plate. The basal bodies of isolated pellicles are obviously undamaged, since all the known structures of native basal bodies are preserved. Even the granular matrix, a labile structure in the lumen of the basal body that probably contains RNA, is preserved.

Isolation and partial characterization of cytoplasmic and wall-bound acid phosphatases from wheat roots

1976 ◽  
Vol 54 (10) ◽  
pp. 1163-1169 ◽  
Author(s):  
Yoichi Hasegawa ◽  
K. R. Lynn ◽  
W. James Brockbank
Keyword(s):  
Sodium Dodecylsulfate ◽  
Gel Filtration ◽  
Creatine Phosphate ◽  
Total Activity ◽  
Exchange Chromatography ◽  
Acid Phosphatases ◽  
Wheat Roots ◽  
Molecular Weights ◽  
Ph Range

In wheat (Triticum aestivum) roots, about 67% of the total activity of acid phosphatase was associated with the cell wall debris, and 35% of it was released from the wall by incubation with 0.8 M NaCl overnight. Three major cytoplasmic and two major wall-bound acid phosphatases were then separated by gel filtration on Sephadex G-75 and ion-exchange chromatography on carboxymethyl cellulose, and some of their characteristics were compared. They showed maximum activities in the same pH range (4.7–5.0) and had broad substrate specificities. They all showed high activity toward ADP. followed by ATP, glucose-6-phosphate, and creatine phosphate and much less activity toward AMP, glucose-1-phosphate, fructose-1,6-diphosphate, and ribose-5-phosphate. The wall-bound enzymes were more active to ADP and ATP than those of the cytoplasm. Mg2+, Ni2+, NaCN, and EDTA had no appreciable effects on the enzymatic activities. However, all enzymes were strongly inhibited by Hg2+ and Fe3+ and, to varied degrees, by Cu2+, Zn2+, Co2+, NaF. p-chloromercuribenzoate, and urea in that order. The molecular weights, estimated by sodium dodecylsulfate gel electrophoresis, ranged from 28 000 to 64 000.

Regional differentiation of the membrane skeleton in Tetrahymena

1987 ◽  
Vol 87 (3) ◽  
pp. 457-463
Author(s):  
N.E. Williams ◽  
J.E. Honts ◽  
R.F. Jaeckel-Williams
Keyword(s):  
Cell Surface ◽  
Cell Shape ◽  
Surface Membrane ◽  
Tetrahymena Pyriformis ◽  
Membrane Skeleton ◽  
Regional Differentiation ◽  
Basal Bodies ◽  
Structural Elements ◽  
Molecular Weights ◽  
Triton X

Antisera have been raised in rabbits against three high molecular weight proteins that are present in Triton X-100-insoluble residues of Tetrahymena pyriformis GL cells. These proteins, called A, B and C, have apparent molecular weights of 235, 135 and 125 (X 10(3)), respectively, in SDS-polyacrylamide gels. The antisera obtained are specific for these proteins, as shown by immunoblotting. Immunolocalization studies are reported that suggest that these proteins are present throughout the epiplasmic layer beneath the cell surface (membrane skeleton). Images obtained with the fluorescence microscope, however, suggest that the membrane skeleton is modified in discrete zones: (1) around somatic basal bodies, (2) within the oral apparatus, (3) in the cytoproct, (4) in contractile vacuole pores, (5) in the fission zone in late division, and (6) at the mating junction in conjugating cells. These regions may represent areas of increased rigidity at the cell surface. The transition from pliable to rigid epiplasm in spatially delimited areas is apparently a recurring theme in cortical morphogenesis in Tetrahymena. Together, the two types of epiplasm probably allow for extensive changes in cell shape while preserving essential relationships between structural elements within the cortex.

Electron Microscope Study of RNA's of Paramyxoviruses

1972 ◽  
Vol 30 ◽  
pp. 196-197
Author(s):  
Ruchama Baum ◽  
J.T. Seto
Keyword(s):  
Electron Microscopy ◽  
Electron Microscope ◽  
Electron Microscope Study ◽  
Sendai Virus ◽  
Sodium Dodecyl ◽  
Rna Molecules ◽  
Virus Particles ◽  
Molecular Weights ◽  
Length Measurements

The ribonucleic acid (RNA) of paramyxoviruses has been characterized by biochemical and physiochemical methods. However, paramyxovirus RNA molecules have not been studied by electron microscopy. The molecular weights of these single-stranded viral RNA molecules are not known as yet. Since electron microscopy has been found to be useful for the characterization of single-stranded RNA, this investigation was initiated to examine the morphology and length measurements of paramyxovirus RNA's.Sendai virus Z strain and Newcastle disease virus (NDV), Milano strain, were used. For these studies it was necessary to develop a method of extracting RNA molecules from purified virus particles. Highly purified Sendai virus was treated with pronase (300 μg/ml) at 37°C for 30 minutes and the RNA extracted by the sodium dodecyl sulfate (SDS)-phenol procedure.

Synthesis and Characterization of Some New Esters Containing Heterocyclic and Derived From Azo Dyes

2019 ◽  
Vol 9 (02) ◽  
Author(s):  
Zena G. Alrecabi ◽  
Zainab Amer ◽  
Naeemah Al-Lami
Keyword(s):  
Schiff Base ◽  
13C Nmr ◽  
Azo Dyes ◽  
Spectral Methods ◽  
Anthranilic Acid ◽  
Heterocyclic Compounds ◽  
Synthesis And Characterization ◽  
Cooh Group ◽  
Molecular Weights

This study including prepared new colored esters containing heterocyclic with high molecular weights. In the first part of work we synthesized azo dyes [1,2] from the reaction p-toluidine with β-naphthol and o-nitro phenol, thin we synthesized Schiff bases [3,4] by the reaction anthranilic acid with benzaldehyde and dimethyl benzaldehyde. The reaction azo dyes (contain OH group) with Schiff base (contain COOH group) these led to produce the new colored esters [A1-A4]. The second part of work was modification the (C=N-) group in esters to heterocyclic compounds by reacting with phenyl iso cyanide to produce new β-lactam [B1-B4] and with anthranilic acid to get new hydroquinazoline [C1-C4]. All these compounds were characterized by physical properties and spectral methods FTIR, 1H-NMR and 13C-NMR.

scholarly journals Semi-Crystalline Hydrophobic Polyamidoamines: A New Family of Technological Materials?

Polymers ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1018
Author(s):  
Massimo Marcioni ◽  
Jenny Alongi ◽  
Elisabetta Ranucci ◽  
Mario Malinconico ◽  
Paola Laurienzo ◽  
...  
Keyword(s):  
Maximum Stress ◽  
Water Resistance ◽  
Prolonged Exposure ◽  
Water Soluble ◽  
Synthesis And Characterization ◽  
Molecular Weights ◽  
New Family ◽  
Methylene Groups ◽  
Methane Flame

The hitherto known polyamidoamines (PAAs) are not suitable as structural materials because they are usually water-soluble or swellable in water. This paper deals with the synthesis and characterization of semi-crystalline hydrophobic PAAs (H-PAAs) by combining different bis-sec-amines with bis-acrylamides obtained from C6–C12 bis-prim-amines. H-PAAs were initially obtained in a solution of benzyl alcohol, a solvent suitable for both monomers and polymers. Their number average molecular weights, M¯n, which were determined with 1H-NMR by evaluating the percentage of their terminal units, varied from 6000 to >10,000. The solubility, thermal properties, ignitability and water resistance of H-PAAs were determined. They were soluble in organic solvents, semi-crystalline and thermally stable. The most promising ones were also prepared using a bulk process, which has never been previously reported for PAA synthesis. In the form of films, these H-PAAs were apparently unaffected by water. The films underwent tensile and wettability tests. They showed similar Young moduli (260–263 MPa), whereas the maximum stress and the stress at break depended on the number of methylene groups of the starting bis-acrylamides. Their wettability was somewhat higher than that of common Nylons. Interestingly, none of the H-PAAs considered, either as films or powders, ignited after prolonged exposure to a methane flame.

scholarly journals Purification and characterization of fat body lipase from the greater wax moth, Galleria mellonella (Lepidoptera: Pyralidae)

2019 ◽  
Vol 81 (1) ◽  
Author(s):  
Rahma R. Z. Mahdy ◽  
Shaimaa A. Mo’men ◽  
Marah M. Abd El-Bar ◽  
Emad M. S. Barakat
Keyword(s):  
Metal Ions ◽  
Kinetic Parameters ◽  
Biochemical Characterization ◽  
Galleria Mellonella ◽  
Fat Body ◽  
Specific Activity ◽  
Larval Instar ◽  
Gel Filtration ◽  
Molecular Weights

Abstract Background Insect lipid mobilization and transport are currently under research, especially lipases and lipophorin because of their roles in the production of energy and lipid transport at a flying activity. The present study has been conducted to purify intracellular fat body lipase for the first time, from the last larval instar of Galleria mellonella. Results Purification methods by combination of ammonium sulfate [(NH4)2SO4] precipitation and gel filtration using Sephadex G-100 demonstrated that the amount of protein and the specific activity of fat body lipase were 0.008633 ± 0.000551 mg/ml and 1.5754 ± 0.1042 μmol/min/mg protein, respectively, with a 98.9 fold purity and recovery of 50.81%. Hence, the sephadex G-100 step was more effective in the purification process. SDS-PAGE and zymogram revealed that fat body lipase showed two monomers with molecular weights of 178.8 and 62.6 kDa. Furthermore, biochemical characterization of fat body lipase was carried out through testing its activities against several factors, such as different temperatures, pH ranges, metal ions, and inhibitors ending by determination of their kinetic parameters with the use of p-nitrophenyl butyrate (PNPB) as a substrate. The highest activities of enzyme were determined at the temperature ranges of 35–37 °C and 37–40 °C and pH ranges of 7–9 and 7–10. The partially purified enzyme showed significant stimulation by Ca2+, K+, and Na+ metal ions indicating that fat body lipase is metalloproteinase. Lipase activity was strongly inhibited by some inhibitors; phenylmethylsulfonyl fluoride (PMSF), ethylene-diaminetetractic acid (EDTA), and ethylene glycoltetraacetic acid (EGTA) providing evidence of the presence of serine residue and activation of enzymes by metal ions. Kinetic parameters were 0.316 Umg− 1 Vmax and 301.95 mM Km. Conclusion Considering the purification of fat body lipase from larvae and the usage of some inhibitors especially ion chelating agents, it is suggested to develop a successful control of Galleria mellonella in near future by using lipase inhibitors.

Preparative isolation and characterization of the B875 complex from Rhodobacter sphaeroides 2.4.1

1988 ◽  
Vol 66 (5) ◽  
pp. 442-448 ◽  
Author(s):  
Rafael Picorel ◽  
Gabriel Gingras
Keyword(s):  
Rhodobacter Sphaeroides ◽  
Phosphatidyl Ethanolamine ◽  
Sodium Dodecyl ◽  
Pigment Analysis ◽  
Preparative Isolation ◽  
Ethanolamine Phosphatidyl ◽  
Isolation And Characterization ◽  
Detergent System ◽  
Triton X

We have developed a simple and efficient method, using a mixed detergent system of sodium dodecyl sulfate and Triton X-100, for the preparative isolation of theB875 complex from Rhodobacter sphaeroides 2.4.1. As a bonus, the method allows the preparation of both the B875 and B800-850 complexes from the same batch of chromatophores. The preparations are spectrally pure, as indicated by absorption and circular dichroism spectroscopy. The latter method suggests that the Qy band of the B875 complex is due to weakly interacting bacteriochlorophyll molecules. Protein and pigment analysis shows that the B875 complex contains 2 mol of bacteriochlorophyll and 2 mol of sphaeroidene per mol of apoprotein (12 266 g), whereas the B800-850 complex contains 3 mol of bacteriochlorophyll and 1 mol of sphaeroidene per mol of apoprotein (11 497 g). While these stoichiometries are in accord with currently accepted models, they disagree with their published experimental basis. Phosphatidyl choline, phosphatidyl ethanolamine, phosphatidyl glycerol, and diphosphatidyl glycerol were found to be present in the B875 complex.

scholarly journals Purification and characterization of bacteriocins-like inhibitory substances from food isolated Enterococcus faecalis OS13 with activity against nosocomial enterococci

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ahmed O. El-Gendy ◽  
Dag A. Brede ◽  
Tamer M. Essam ◽  
Magdy A. Amin ◽  
Shaban H. Ahmed ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Antimicrobial Agents ◽  
Food Samples ◽  
Proteinase K ◽  
Clinical Samples ◽  
Bile Salt Hydrolase ◽  
Antibiotic Resistant ◽  
Molecular Weights ◽  
Global Threat

AbstractNosocomial infections caused by enterococci are an ongoing global threat. Thus, finding therapeutic agents for the treatment of such infections are crucial. Some Enterococcus faecalis strains are able to produce antimicrobial peptides called bacteriocins. We analyzed 65 E. faecalis isolates from 43 food samples and 22 clinical samples in Egypt for 17 common bacteriocin-encoding genes of Enterococcus spp. These genes were absent in 11 isolates that showed antimicrobial activity putatively due to bacteriocins (three from food, including isolate OS13, and eight from clinical isolates). The food-isolated E. faecalis OS13 produced bacteriocin-like inhibitory substances (BLIS) named enterocin OS13, which comprised two peptides (enterocin OS13α OS13β) that inhibited the growth of antibiotic-resistant nosocomial E. faecalis and E. faecium isolates. The molecular weights of enterocin OS13α and OS13β were determined as 8079 Da and 7859 Da, respectively, and both were heat-labile. Enterocin OS13α was sensitive to proteinase K, while enterocin OS13β was resistant. Characterization of E. faecalis OS13 isolate revealed that it belonged to sequence type 116. It was non-hemolytic, bile salt hydrolase-negative, gelatinase-positive, and sensitive to ampicillin, penicillin, vancomycin, erythromycin, kanamycin, and gentamicin. In conclusion, BLIS as enterocin OS13α and OS13β represent antimicrobial agents with activities against antibiotic-resistant enterococcal isolates.

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