scholarly journals Biosynthesis of Pb44, the protective antigen of sporozoites of Plasmodium berghei.

1981 ◽  
Vol 154 (4) ◽  
pp. 1225-1236 ◽  
Author(s):  
N Yoshida ◽  
P Potocnjak ◽  
V Nussenzweig ◽  
R S Nussenzweig

In a previous paper (2) we identified a protective antigen (Pb44) of the surface membrane of sporozoites of Plasmodium berghei by means of a monoclonal antibody. Immunoprecipitation of extracts of mature salivary gland sporozoites, metabolically labeled with L[35S]methionine using the same monoclonal antibody, revealed three specific polypeptides: *Pb44, *Pb52, and *Pb54. Metabolically labeled *Pb44 is probably identical to the protective antigen previously identified by surface labeling. Both proteins have the same molecular weights and isoelectric points under denaturing conditions, and they share an epitope. Moreover, *Pb44 also seems to be located on the cell membrane. The results of pulse-chase experiments strongly suggest that *Pb52 is the precursor of *Pb44. The relationship between *Pb54 and the protective antigen is unknown. The three polypeptides seem to be strictly associated with only one of the developmental stage of the parasite. They were not detected in blood forms and were found in minute amounts in sporozoites from the midgut of mosquitoes. In contrast, in mature salivary gland sporozoites they constitute main products of protein synthesis.

Parasitology ◽  
1990 ◽  
Vol 100 (1) ◽  
pp. 115-124 ◽  
Author(s):  
M. A. Ouaissi ◽  
A. Taibi ◽  
J. Cornette ◽  
P. Velge ◽  
B. Marty ◽  
...  

SummaryThe surface antigens ofTrypanosoma cruzitrypomastigotes were identified by immunoprecipitation and were compared with metabolically labelled excretory—secretory products (ES) released by the parasitesin vitro. A series of major immunogenic components in the ES antigens were revealed (160 kDa, 130 kDa and 80–110 kDa). The trypomastigote surface also bears the 130 kDa band and the 80–110 kDa complex. Competition experiments demonstrated the common antigenic structure of the ES and the surface antigens. Two-dimensional analysis of ES antigens immunoprecipitated by human Chagasic serum revealed several spots in the 80–110 kDa region with a wide range of isoelectric points (PI between 5·4 and 6·7). This reflects a charge heterogeneity of these polypeptides. The trypomastigote 85 kDa polypeptide was also identified in the ES antigens by using a monoclonal antibody against this antigen. Two-dimensional analysis of the 85 kDa proteins shed from the surface of trypomastigotes and immunoprecipitated by the monoclonal antibody 155D3 showed 2 major spots: a major part of the 85 kDa polypeptide was found at pH 6·5–6·6, whereas a substantial amount of the antigen was found at pH 5·7. An additional component with molecular weight of approximately 58 kDa and isoelectric points of 6·5 and 6·6, was also visualized. Detection of the 85 kDa polypeptide circulating in serum from patients with acute and chronic Chagas' disease was achieved using an enzyme-linked immunosorbent assay. In addition, the data obtained showed that a polyclonal antibody to the 85 kDa polypeptide could be used to passively induce a partial protection of Fischer rats against acute lethal infection. Thus, the antigens recognized by polyclonal antibody appear to play a role in the development of protective immunity againstT. cruzi.


2018 ◽  
Vol 3 (1) ◽  
pp. 40-44 ◽  
Author(s):  
Karim Mohammed Xider

The current work the effect of Actara insecticide belongs to chemical family Neonicotinoid. The active component of thiamethoxam in three concentrations: 0.750 ppm, 1.5 ppm and 2.25ppm   on adult house fly salivary glands. Histopathological and morphological effects revealed important alterations produced by this insecticide in histological and morphology of the adult house fly gland tissue categorized by increasing gland duct lumen diameter. These alterations are possibly related with excretion function of salivary gland might be accountable for removing this insecticide. Results show thiamethoxam is a powerful insecticide that performances histologically in salivary glant tissue, triggering alterations in the glands  form, cytoplasm  with extreme vacuolation ,disruption cell membrane, obvious disorganization tissues cells, terminating in progressive deteriorating phase with changes in nucleus glandular cell's, such alterations occurred together in its size and form of gland, disintegration of nucleus, and presence of apoptosis(fragmentation) nucleus, accelerating the process of glandular degeneration ,and interfering with feeding process of house fly particularly when the peak concentration of  insecticide  was used.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yufang Xiang ◽  
Yuanyuan Zheng ◽  
Shaobo Liu ◽  
Gang Liu ◽  
Zhi Li ◽  
...  

AbstractWestern blotting (WB) is one of the most widely used techniques to identify proteins as well as post translational modifications of proteins. The selection of electroblotted membrane is one of the key factors affecting the detection sensitivity of the protein which is transferred from gel to membrane in WB. The most common used membranes are polyvinylidene fluoride (PVDF) and nitrocellulose (NC) membranes. Which membrane of these two is more suitable for WB has not been reported so far. Here, by incubating proteins which were transferred to PVDF or NC membranes with a series of antibodies and different types of lectins, we investigated the relationship between the binding ability of these two membranes to proteins or glycoproteins and the molecular weight of the target protein. The antibody re-probed ability of the two membranes was also explored. Moreover, we verified the above results by directly incubating proteins having different molecular weights onto PVDF or NC membranes. Bound proteins were stained with direct blue-71, and the staining intensity was quantitated by scanning and densitometry.


1980 ◽  
Vol 87 (3) ◽  
pp. 828-832 ◽  
Author(s):  
K Sandvig ◽  
S Olsnes

At neutral pH, NH4Cl and chloroquine protected cells against diphtheria toxin. A brief exposure of the cells to low pH (4.5-5.5) at 37 degrees completely abolished this protection. When, to cells preincubated with diphtheria toxin and NH4Cl, neutralizing amounts of anti-diphtheria toxin were added before the pH was lowered, the toxic effect was considerably reduced, but it was not completely abolished. A much stronger toxic effect was seen when antibodies were added immediately after incubation at low pH. Upon a short incubation with diphtheria toxin at low pH, the rate of protein synthesis in the cells decreased much faster than when the normal pH was maintained. The data suggest that, at low pH, diphtheria toxin (or its A fragment) penetrates directly through the surface membrane of the cell. The possibility is discussed that, when the medium has a neutral pH, the entry of diphtheria toxin involves adsorptive endocytosis and reduction of the pH in the vesicles possibly by fusion with lysosomes. Low pH did not facilitate the entry of the closely related toxins abrin, ricin, and modeccin.


1985 ◽  
Vol 16 (3) ◽  
pp. 345-354 ◽  
Author(s):  
Donald A. Harn ◽  
Masao Mitsuyama ◽  
Edward D. Huguenel ◽  
Lynette Oligino ◽  
John R. David

Hybridoma ◽  
1983 ◽  
Vol 2 (4) ◽  
pp. 393-402 ◽  
Author(s):  
KENNETH A. FOON ◽  
STEPHEN BUESCHER ◽  
EDWARD S. KIMBALL ◽  
LAURA C. HUANG ◽  
HENRY C. STEVENSON ◽  
...  

2014 ◽  
Vol 21 (12) ◽  
pp. 1308-1319
Author(s):  
Setsuko Komatsu ◽  
Myeong W. Oh ◽  
Hee Y. Jang ◽  
Soo J. Kwon ◽  
Hye R. Kim ◽  
...  

Plant root systems form complex networks with the surrounding soil environment and are controlled by both internal and external factors. To better understand the function of root tips of soybean during germination, three proteomic techniques were used to analyze the protein profiles of root tip cells. Proteins were extracted from the root tips of 4-dayold soybean seedlings and analyzed using two-dimensional (2D) gel electrophoresis-based proteomics, SDS-gel based proteomics, and gel-free proteomics techniques. A total of 121, 862, and 341 proteins were identified in root tips using the 2D gel-based, SDS gel-based, and gel-free proteomic techniques, respectively. The proteins identified by 2D gel-based proteomic analysis were predominantly localized in the cytoplasm, whereas nuclear-localized proteins were most commonly identified by the SDS gel-based and gel-free proteomics techniques. Of the 862 proteins identified in the SDS gelbased proteomic analysis, 190 were protein synthesis-related proteins. Furthermore, 24 proteins identified using the 2Dgel based proteomic technique shifted between acidic and basic isoelectric points, and 2 proteins, heat shock protein 70.2 and AAA-type ATPase, displayed two different molecular weights at the same isoelectric point. Taken together, these results suggest that a number of proteins related to protein synthesis and modification are activated in the root tips of soybean seedlings during germination.


1987 ◽  
Vol 7 (11) ◽  
pp. 4118-4121
Author(s):  
D A Talmage ◽  
M Blumenfeld

Phosphorylation of histone H1 is developmentally regulated in Drosophila spp. It cannot be detected in preblastoderm embryos or polytene salivary gland cells, but in cellular blastoderm, postblastoderm embryo, and amitotic adult head nuclei, it occurs with a frequency of roughly 4 x 10(5) molecules per nucleus. We used pulse-labeling to study the relationship between H1 synthesis and modification in cultured cells. These results reveal that the H1-associated phosphate is stable and suggest that Drosophila H1 is synthesized, translocated to the nucleus, associated with chromatin, and then phosphorylated. Partial tryptic digestion of Drosophila H1 revealed that the phosphorylation site is located within the globular, central domain of the protein. Thus, the developmentally regulated phosphorylation of Drosophila H1 presents two contrasts with previously studied H1 phosphorylation. It is not correlated with DNA replication, and it is located in the central domain of the protein.


1947 ◽  
Vol 20 (4) ◽  
pp. 984-989
Author(s):  
David M. French ◽  
Roswell H. Ewart

Abstract Osmotic molecular weight measurements have been made on a sample of unfractionated GR-S and on eight fractions of this material. The molecular weights ranged from 10,000 to approximately 1,000,000, with a number average at 92,000. The relationship between molecular weight and viscosity for GR-S was determined. A simple all-glass osmometer for use in hydrocarbon solvents is described, and information on its use and the membranes employed is given.


1987 ◽  
Vol 167 (2) ◽  
pp. 239-244 ◽  
Author(s):  
Gary A. Peltz ◽  
Byron Gallis ◽  
B. Matija Peterlin

Sign in / Sign up

Export Citation Format

Share Document