scholarly journals Surface organization and composition of Euglena. II. Flagellar mastigonemes

1978 ◽  
Vol 77 (3) ◽  
pp. 805-826 ◽  
Author(s):  
GB Bouck ◽  
A Rogalski ◽  
A Valaitis

The surface of the Euglena flagellum is coated with about 30,000 fine filaments of two distinct types. The longer of these nontubular mastigonemes (about 3 micron) appear to be attached to the paraflagellar rod whereas the shorter nontubular mastigonemes (about 1.5 micron) are the centrifugally arranged portions of a larger complex, which consists of an attached unit parallel to and outside of the flagellar membrane. Units are arranged laternally in near registration and longitudinally overlap by one-half of a unit length. Rows of mastigoneme units are firmly attached to the axoneme microtubules or to the paraflagellar rod as evidenced by their persistence after removal of the flagellar membrane with neutral detergents. SDS-acrylamide gels of whole flagella revealed about 30 polypeptides, of which two gave strong positive staining with the periodic acid-Schiff (PAS) procedure. At least one of these two bands (glycoproteins) has been equated with the surface mastigonemes by parallel analysis of isolated and purified mastigonemes, particularly after phenol extraction. The faster moving glycoprotein has been selectively removed from whole flagella and from the mastigoneme fraction with low concentrations of neutral detergents at neutral or high pH. The larger glycoprotein was found to be polydisperse when electrophoresed through 1% agarose/SDS gels. Thin-layer chromatography of hydrolysates of whole flagella or of isolated mastigonemes has indicated that the major carbohydrate moiety is the pentose sugar, xylose, with possibly a small amount of glucose and an unknown minor component.

1990 ◽  
Vol 36 (5) ◽  
pp. 327-335 ◽  
Author(s):  
Stephen H. Smith ◽  
Robert G. E. Murray

Aquaspirillum sinuosum cell walls bear two paracrystalline, proteinaceous surface layers (S layers). Each shows a different symmetry: the inner layer is closely apposed to the outer membrane and is a tetragonal array (90° axes; 5-nm units; repeat frequency 8 nm); the outer layer is a hexagonal array on the external surface (14-nm units; repeat frequency 18 nm) and, although the units have a six-pointed stellate form, the linkage between units is not resolved. The outer layer consists of a major 130-kDa protein and a 180-kDa minor component; these co-extract, co-assemble, and are inseparable by hydroxylapatite chromatography or by recrystallization. The solubilizing effects of reagents suggest stabilization by hydrogen bonding and Ca2+. The two outer layer proteins are serologically related and show partial identity by peptide mapping. Periodic acid – Schiff staining of the 180-kDa band suggests that this may be a glycosylated form of the 130-kDa component. The inner layer components form a doublet of 75- and 80-kDa polypeptides with extreme resistance to extraction. Close apposition to the outer membrane, resistance to chaotropes, aqueous insolubility, and behaviour in charge-shift electrophoresis suggest hydrophobic interaction between subunits and an integral association with the outer membrane. Key words: bacterial surface, cell wall, surface layers, cell-wall proteins, cell-wall assembly.


2019 ◽  
Vol 20 (1) ◽  
pp. 38
Author(s):  
Yusrizal Akmal ◽  
Chairun Nisa ◽  
Savitri Novelina

The study aims to reveal the morphology of the male sex accessory glands of the pangolin at macroscopic and microscopic levels. Macroscopic observation included measurement of length and thickness of each accessory gland while microscopic observation, sample of each accessory gland was processed by histology technique with paraffin method and sliced with 3-5 ?m thickness and stained with hematoxylin-eosin (HE) staining for general structural observation, coloration of alcian blue (AB) pH 2.5 and periodic acid Schiff (PAS) to observe the distribution of acid and neutral mucopolysaccharides in each glands. The results showed that the male sex accessory glands of the pangolin consist of vesicular gland and prostate, and bulbourethral gland which were not observed macroscopically. The average length and thickness of vesicular gland were 1.07 cm and 0.41 cm, while the prostate was 1.17 cm and 0.54 cm respectively. All accessory glands were lobulated and separated with a thick connective tissue into lobes and lobules. Acinar cells in the vesicular glands were a serous type, whereas acinar cells in the prostate and bulbourethral gland were the mucous types. Secretion of vesicular gland contains neutral mucopolysaccharide with low concentrations and prostate containing neutral mucopolysaccharide with moderate conJurnal Veteriner Maret 2019 Vol. 20 No. 1 : 38 - 47 pISSN: 1411-8327; eISSN: 2477-5665 DOI: 10.19087/jveteriner.2019.20.1.38 Terakreditasi Nasional, Dirjen Penguatan Riset dan Pengembangan, online pada http://ojs.unud.ac.id/index.php/jvet Kemenristek Dikti RI S.K. No. 36a/E/KPT/201639 centrations, and did not secrete acid mucopolysaccharide. Secretion of bulbourethral glands contains neutral and acidic mucopolysaccharide with strong concentrations. Macroscopically the bulbourethral gland is not observed but has a high carbohydrate which acts as to produce of cement plasma and rinsing urethra from urine.   


1980 ◽  
Vol 86 (2) ◽  
pp. 424-435 ◽  
Author(s):  
A A Rogalski ◽  
G B Bouck

Purified flagella from Euglena yield a unique high molecular weight glycoprotein when treated with low concentrations of nonionic detergents. This glycoprotein termed "xyloglycorien" cannot be extracted from other regions of the cell, although a minor component that coextracts with xyloglycorien does have a counterpart in deflagellated cell bodies. Xyloglycorien is tentatively identified with a flagellar surface fuzzy layer that appears in negatively stained membrane vesicles of untreated flagella but not in similar vesicles after Nonidet P-40 extraction. The localization of xyloglycorien is further confirmed to be membrane associated by reciprocal extraction experiments using 12.5 mM lithium diiodosalicylate (LIS), which does not appreciably extract xyloglycorien, visibly solubilize membranes, or remove the fuzzy layer. Rabbit antibodies directed against the two major flagellar glycoproteins (xyloglycorien and mastigonemes) to some extent cross react, which may in part be caused by the large percentage of xylose found by thin-layer chromatography (TLC) analysis to be characteristic of both antigens. However, adsorption of anti-xyloglycorien sera with intact mastigonemes produced antibodies responding only to xyloglycorien, and vice versa, indicating the nonidentity of the two antigens. Antibodies or fragments of these antibodies used in immunofluorescence assays demonstrated that xyloglycorien is confined to the flagellum and possibly the adjacent reservoir and gullet. Binding could not be detected on the cell surface. The sum of these experiments suggests that, in addition to mastigonemes, at least one major membrane glycoprotein in Euglena is restricted to the flagellar domain and is not inserted into the contiguous cell surface region.


1985 ◽  
Vol 225 (2) ◽  
pp. 553-556 ◽  
Author(s):  
C H Evans

Clostridiopeptidase A (EC 3.4.24.3) did not bind to a collagen affinity column in the absence of Ca2+, but did so in the presence of lanthanide ions (Ln3+). The sequestered enzyme could be eluted with EGTA. For the four Ln3+ ions tested, the order of efficiency in promoting enzyme binding, Sm3+ greater than Lu3+ greater than Er3+ much greater than La3+, reflected their relative abilities to inhibit clostridiopeptidase A. By using Sm3+ as an adjunct, it proved possible to separate a highly active preparation of collagenase from crude clostridial collagenase. Sodium dodecyl sulphate/polyacrylamide-gel-electrophoretic analysis of the preparation revealed a major protein of Mr 95000 and a minor component of Mr 82000. As both were stained by periodic acid/Schiff reagent, they were probably glycoproteins.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Shuhei Naka ◽  
Kaoruko Wato ◽  
Taro Misaki ◽  
Seigo Ito ◽  
Daiki Matsuoka ◽  
...  

AbstractThe mechanisms underlying immunoglobulin A nephropathy (IgAN), the most common chronic form of primary glomerulonephritis, remain poorly understood. Streptococcus mutans, a Gram-positive facultatively anaerobic oral bacterium, is a common cause of dental caries. In previous studies, S. mutans isolates that express Cnm protein on their cell surface were frequently detected in IgAN patients. In the present study, inoculation of Cnm-positive S. mutans in the oral cavities of 2-week-old specific-pathogen free Sprague–Dawley rats fed a high-sucrose diet for 32 weeks produced severe dental caries in all rats. Immunohistochemical analyses of the kidneys using IgA- and complement C3-specific antibodies revealed positive staining in the mesangial region. Scanning electron microscopy revealed a wide distribution of electron dense deposits in the mesangial region and periodic acid-Schiff staining demonstrated prominent proliferation of mesangial cells and mesangial matrix. These results suggest that IgAN-like glomerulonephritis was induced in rats with severe dental caries by Cnm-positive S. mutans.


1978 ◽  
Vol 78 (3) ◽  
pp. 894-909 ◽  
Author(s):  
E Rodriguez Boulan ◽  
D D Sabatini ◽  
B N Pereyra ◽  
G Kreibich

Rat liver microsomal glycoproteins were purified by affinity chromatography on concanavalin A Sepharose columns from membrane and content fractions, separated from rough microsomes (RM) treated with low concentrations of deoxycholate (DOC). All periodic acid-Schiff (PAS)-positive glycoproteins of RM showed affinity for concanavalin A Sepharose; even after sodium dodecyl sulfate (SDS) acrylamide gel electrophoresis, most of the microsomal glycoproteins bound [125I]concanavalin A added to the gels, as detected by autoradiography. Two distinct sets of glycoproteins are present in the membrane and content fractions derived from RM. SDS acrylamide gel electrophoresis showed that RM membranes contain 15--20 glycoproteins (15--22% of the total microsomal protein) which range in apparent mol wt from 23,000 to 240,000 daltons. A smaller set of glycoproteins (five to seven polypeptides), with apparent mol wt between 60,000 and 200,000 daltons, was present in the microsomal content fraction. The disposition of the membrane glycoproteins with respect to the membrane plane was determined by selective iodination with the lactoperoxidase (LPO) technique. Intact RM were labeled on their outer face with 131I and, after opening of the vesicles with 0.05% DOC, in both faces with 125I. An analysis of iodination ratios for individual proteins separated electrophoretically showed that in most membrane glycoproteins, tyrosine residues are predominantly exposed on the luminal face of the vesicles, which is the same face on which the carbohydrate moieties are exposed. Several membrane glycoproteins are also exposed on the cytoplasmic surface and therefore have a transmembrane disposition. In this study, ribophorins I and II, two integral membrane proteins (mol wt 65,000 and 63,000) characteristic of RM, were found to be transmembrane glycoproteins. It is suggested that the transmembrane disposition of the ribophorins may be related to their possible role in ribosome binding and in the vectorial transfer of nascent polypeptides into the microsomal lumen.


2000 ◽  
Vol 37 (2) ◽  
pp. 188-192 ◽  
Author(s):  
C. D. Buergelt ◽  
A. Adjiri-Awere

A bilateral, locally invasive renal oncocytoma was diagnosed in a 10-year-old spayed female Greyhound dog. The diagnosis was based on positive staining of the tumor with the periodic acid-Schiff reaction prior to diastase treatment, on the immunohistochemical expression of cytoplasmic cytokeratin, and on the prominence of mitochondria in the tumor cells.


2021 ◽  
Vol 156 (Supplement_1) ◽  
pp. S124-S124
Author(s):  
M Kilpatrick ◽  
D Lewin

Abstract Introduction/Objective Hyaline arteriolosclerosis is a common feature of diabetic microangiopathy. It results from hyperglycemia-induced endothelial cell dysfunction and can be found in many sites including the retina, kidney, and skin. This histologic finding is important because studies have shown that in the kidney it is an independent risk factor for cardiovascular complications. To our knowledge, an association between hyperglycemia and hyaline arteriolosclerosis in the liver has not be studied. We aimed to investigate whether chronic hyperglycemia is associated with this histologic finding in liver arterioles. Methods/Case Report The first 50 liver biopsies performed at our institution starting January 1, 2020 were scanned into a digital pathology system (Philips, Cambridge, MA). For each biopsy, the patient’s highest recorded hemoglobin A1c (HbA1c) up to one year from the date of biopsy was recorded. The biopsies were then grouped into two groups: those from patients with a HbA1c greater than 6.5%, and those with a HbA1c value less than 6.5 %. Next, the digested periodic acid Schiff (DPAS) intensity of the arteriolar vessels in each biopsy was graded 0 to 3 by a single pathology resident who was blinded to its corresponding HbA1c group. Grade 0 to 1 was considered negative staining. Grade 2 to 3 was considered positive staining and indicative of hyaline arteriolosclerosis. By the end of the data collection, each case had been given a staining category and a HbA1c group. A 2 x 2 contingency table was constructed. Results (if a Case Study enter NA) 37 of 50 patients had a recorded HbA1c meeting the study criteria. Of these 37 patients, 11 had an HbA1c greater than 6.5 % while 26 had an HbA1c less than 6.5%. Seven of the 11 biopsies from patients with an elevated HbA1c showed positive staining. Six of the 26 biopsies from patients with an HbA1c less than 6.5% showed positive staining. Conclusion We hypothesized that patients living with hyperglycemia may be more likely to exhibit hepatic hyaline arteriolosclerosis. A chi-squared test of independence was performed to examine the association between a liver biopsy’s HbA1c group and staining category. The relation between these variables was significant at p = < .05, χ 2 (2, N= 36) = 5.57, p = .0182, indicating liver biopsies with a HbA1c greater than 6.5 % are more likely to have this histologic finding. Future studies are needed to characterize diabetic hepatopathy, and its relatedness to macrovascular complications.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e22102-e22102
Author(s):  
P. Betta ◽  
R. Libener ◽  
S. Orecchia ◽  
M. Salvio ◽  
E. Arnolfo ◽  
...  

e22102 Background: There is still no single test that can reliably identify malignant mesothelial cells. Recently soluble MES and OPN have been proposed as novel serum markers for MPM but a definitive consensus on their use in routine is still lacking. This study aims at 1. analysing the essential pathological features of a series of consecutive MPMs from a single institution and 2. assessing the tumour tissue expression of OPN and MES and speculating about the potential biological role of these molecules in MPM. Methods: All MPMs diagnosed between 1999 and 2008 were retrieved from the archives of the Pathology Unit of Alessandria Hospital. All the diagnoses had been made on the basis of conventional light microscopy features supplemented by a mucin stain (periodic acid-Schiff with and without diastase treatment) and a panel of immunostains (carcinoembryonic antigen, CD15/LeuM1, BerEP4, calretinin and cytokeratin 5). Immunostaining for OPN (polyclonal antibody) and MES (monoclonal antibody, clone 5B2) was performed using the labelled streptavidin-biotin method, and the staining intensity and extent were assessed. Results: The study group consisted of 50 males and 20 females with a mean age at diagnosis of 78.4 years (range 47–92). Histopathology was epithelial, mixed, and sarcomatous in 52, 12, and 6 patients respectively. OPN positivity (percentage of positive tumour cells >10%) was observed in 67 MPMs (96%) mostly in a granular cytoplasmic pattern and with an intensity ranging from weak (25%) to moderate (31%) and strong (44%). MES positivity (percentage of positive tumour cells >10%) was recorded in 60 MPMs (86%), of which 36% exhibited a weak, 36% a moderate and 28% a strong immunostaining in a membrane pattern. MES was positive in 100% of epithelial MPMs, in 67% of mixed and in 0% of sarcomatous. Positivity was restricted to the epithelial component in mixed MPMs. Conclusions: The high expression of OPN in MPM, irrespective of the histotype, seems to point to a role of this molecule as a marker of malignant transformation of mesothelial cells, while the restriction of positive staining for MES to the epithelial phenotype supports a role of MES as a marker of epithelial differentiation in MPM. No significant financial relationships to disclose.


1998 ◽  
Vol 88 (2) ◽  
pp. 319-323 ◽  
Author(s):  
Hitoshi Kobata ◽  
Akinori Kondo ◽  
Koichi Iwasaki ◽  
Hirofumi Kusaka ◽  
Hidefumi Ito ◽  
...  

✓ A case of chordoid meningioma occurring in a 15-year-old girl is presented. The patient manifested seizures as the initial symptom and subsequently exhibited subclinical microcytic hypochromic anemia. The tumor, located in the falcotentorial region and associated with diffuse edema, was totally resected. On histological examination of the surgical specimen, the clustering pattern of partly vacuolated cells in the mucoid stroma mimicked chordoma; however, positive staining of individual cells for vimentin and epithelial membrane antigen led to a diagnosis of meningioma. Interestingly, the tumor cells were surrounded by a periodic acid—Schiff— and type IV collagen—positive substance. Electron microscopy demonstrated a strikingly dense and thick basal lamina. The patient's microcytic hypochromic anemia disappeared after the tumor was removed. Both the clinical and pathological features of this case resemble those of chordoid meningioma, a rare meningioma variant.


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