scholarly journals Subcellular Localization of the Intracellular Survival-Enhancing Eis Protein of Mycobacterium tuberculosis

2001 ◽  
Vol 69 (7) ◽  
pp. 4295-4302 ◽  
Author(s):  
John L. Dahl ◽  
Jun Wei ◽  
James W. Moulder ◽  
Suman Laal ◽  
Richard L. Friedman

ABSTRACT Mycobacterium tuberculosis is a facultative intracellular pathogen that has evolved the ability to survive and multiply within human macrophages. It is not clear how M. tuberculosis avoids the destructive action of macrophages, but this ability is fundamental in the pathogenicity of tuberculosis. A gene previously identified in M. tuberculosis, designatedeis, was found to enhance intracellular survival ofMycobacterium smegmatis in the human macrophage-like cell line U-937 (J. Wei et al., J. Bacteriol. 182:377–384, 2000). Wheneis was introduced into M. smegmatis on a multicopy vector, sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed the appearance of a unique 42-kDa protein band corresponding to the predicted molecular weight of the eisgene product. This band was electroeluted from the gel with a purity of >90% and subjected to N-terminal amino acid sequencing, which demonstrated that the 42-kDa band was indeed the protein product ofeis. The Eis protein produced by M. tuberculosis H37Ra had an identical N-terminal amino acid sequence. A synthetic polypeptide corresponding to a carboxyl-terminal region of the deduced eis protein sequence was used to generate affinity-purified rabbit polyclonal antibodies that reacted with the 42-kDa protein in Western blot analysis. Hydropathy profile analysis showed the Eis protein to be predominantly hydrophilic with a potential hydrophobic amino terminus. Phase separation of M. tuberculosis H37Ra lysates by the nonionic detergent Triton X-114 revealed the Eis protein in both the aqueous and detergent phases. After fractionation of M. tuberculosis by differential centrifugation, Eis protein appeared mainly in the cytoplasmic fraction but also in the membrane, cell wall, and culture supernatant fractions as well. Forty percent of the sera from pulmonary tuberculosis patients tested for anti-Eis antibody gave positive reactions in Western blot analysis. Although the function of Eis remains unknown, evidence presented here suggests it associates with the cell surface and is released into the culture medium. It is produced during human tuberculosis infection and therefore may be an important M. tuberculosis immunogen.

2005 ◽  
Vol 68 (1) ◽  
pp. 157-163 ◽  
Author(s):  
MI-HEE KIM ◽  
YOON-JUNG KONG ◽  
HONG BAEK ◽  
HYUNG-HWAN HYUN

Strain GO5, a bacteriocin-producing bacterium, was isolated from green onion kimchi and identified as Micrococcus sp. The bacteriocin, micrococcin GO5, displayed a broad spectrum of inhibitory activity against a variety of pathogenic and nonpathogenic microorganisms, as tested by the spot-on-lawn method; its activity spectrum was almost identical to that of nisin. Micrococcin GO5 was inactivated by trypsin (whereas nisin was not) and was completely stable at 100°C for 30 min and in the pH range of 2.0 to 7.0. Micrococcin GO5 exhibited a typical mode of bactericidal activity against Micrococcus flavus ATCC 10240. It was purified to homogeneity through ammonium sulfate precipitation, ultrafiltration, and CM-Sepharose column chromatography. The molecular mass of micrococcin GO5 was estimated to be about 5.0 kDa by tricine–sodium dodecyl sulfate–polyacrylamide gel electrophoresis and in situ activity assay with the indicator organism. The amino acid sequence of micrococcin GO5 lacks lanthionine and β-methyllanthionine and is rich in hydrophobic amino acids and glycine, providing the basis for the high heat stability of this bacteriocin. The N-terminal amino acid sequence of micrococcin GO5 is Lys-Lys-Ser-Phe-Cys-Gln-Lys, and no homology to bacteriocins reported previously was observed in the amino acid composition or N-terminal amino acid sequence. Based on the physicochemical properties, small molecular size, and inhibition of Listeria monocytogenes, micrococcin GO5 has been placed with the class II bacteriocins, but its broad spectrum of activity differs from that of other bacteriocins in this class.


Plant Disease ◽  
2000 ◽  
Vol 84 (5) ◽  
pp. 595-595 ◽  
Author(s):  
N. L. Robertson ◽  
S. K. Brumfield

Barley yellow streak mosaic virus (BaYSMV) was first described and reported in Montana and Alberta, Canada, more than 17 years ago (1). Since then, it has been detected in two other locations: Pocatello Valley, ID (3), and across the border in Utah. BaYSMV has now been found in the Alaskan interior. In July 1999, dry-land barley (Hordeum vulgare L.) growing in University of Alaska-Fairbanks experimental plots exhibited symptoms similar to those described for BaYSMV, including parallel chlorotic streaks and leaf banding. Mechanical inoculation of Nicotiana benthamiana with diseased barley sap produced systemic mosaic symptoms. As previously reported for BaYSMV sap-transmission tests (2), parallel inoculations to barley plants yielded no symptoms. Electron microscopy of leaf dips and minipurifications of infected N. benthamiana revealed long filamentous particles that matched the size and shape reported for BaYSMV (1). Ultrathin sections of diseased barley and N. benthamiana leaves displayed characteristic virus particles. BaYSMV was confirmed by immuno-sorbent electron microscopy assays (4) and western blot analysis with polyclonal antiserum. Long filamentous BaYSMV particles appeared only on grids coated with BaYSMV antiserum and exposed to diseased N. benthamiana sap. Total protein extracts from diseased barley tissue and inoculated N. benthamiana, as well as with protein extracted from partially purified preparations, were applied to a 12% sodium dodecyl sulfate-polyacrylamide gel electrophoresis minigel and stained with Coomassie blue. Diseased samples, but not healthy controls, contained a protein of ≈33 kDa that was within the size range of a previously described protein from partially purified BaYSMV particles (2). Western blot analysis with an Immuno-Blot alkaline phosphatase assay system (Bio-Rad Laboratories, Hercules, CA) confirmed that the protein reacted with polyclonal BaYSMV. This is the first serological documentation of a BaYSMV-specific protein and that the ≈33-kDa protein is the main antigen recognized by the BaYSMV polyclonal antiserum. Based on virus particle shape and size, symptomology, mechanical transmission host range, and serology, we conclude that BaYSMV is associated with the barley disease observed. Barley yellow streak mosaic virus disease outbreaks are associated with recurring drought and are accompanied by infestations of the brown wheat mite vector, Petrobia latens Müller (1), so it is not surprising that this report coincides with abnormally dry conditions occurring throughout the 1990s in the interior of Alaska. References: (1) N. L. Robertson and T. W. Carroll. Science 240:1188, 1988. (2) N. L. Robertson and T. W. Carroll. Plant Dis. 75:839, 1991. (3) J. S. Skaf et al. Plant Dis. 76:861, 1992. (4) J. S. Skaf and T. W. Carroll. Plant Dis. 79:1003, 1995.


1973 ◽  
Vol 74 (2) ◽  
pp. 226-236 ◽  
Author(s):  
Michel Chrétien ◽  
Claude Gilardeau

ABSTRACT A protein isolated from ovine pituitary glands has been purified, and its homogeneity assessed by NH2- and COOH-terminal amino acid determination, ultracentrifugation studies, and polyacrylamide gel electrophoresis after carboxymethylation. Its chemical and immunochemical properties are closely similar to those of beef and pork neurophysins, less similar to those of human neurophysins. It contains no tryptophan (like other neurophysins) or histidine (like all except bovine neurophysin-I and human neurophysins). It has alanine at the NH2-terminus and valine at the COOH-terminus. Its amino acid composition is similar to, but not identical with those of porcine and bovine neurophysins.


1978 ◽  
Vol 171 (1) ◽  
pp. 99-107 ◽  
Author(s):  
M A Kerr ◽  
R R Porter

The second component of human complement (C2) was purified by a combination of euglobulin precipitation, ion-exchange chromatography, (NH4)2SO4 precipitation and affinity chromatography. The final product was homogeneous by the criterion of polyacrylamide-gel electrophoresis and represents a purification of about 4000-fold from serum with 15-20% yield. Component C2 comprises a single carbohydrate-containing polypeptide chain, with an apparent mol.wt. of 102000; alanine is the N-terminal amino acid. The molecule is rapidly cleaved by activated subcomponent C1s with the loss of haemolytic activity to yield two fragments with apparent mol.wts. of 74000 and 34000. These fragments are not linked by disulphide bonds and can be easily separated. A second protein isolated during the purification of component C2 was identified by its haemolytic and antigenic properties as complement Factor B, the protein serving an analogous function to component C2 in the alternative pathway. The protein, which is also a single carbohydrate-containing polypeptide chain, has an apparent mol.wt. of 95000 and threonine as N-terminal amino acid. The amino acid analyses of component C2 and Factor B are compared.


2012 ◽  
Vol 49 (No. 8) ◽  
pp. 305-311 ◽  
Author(s):  
G. Ozbey ◽  
H. Ongor ◽  
D. T Balik ◽  
V. Celik ◽  
A. Kilic ◽  
...  

In the present study, lung, trachea and serum samples from broiler flocks slaughtered at an abattoir in Elazig province located in the East of Turkey were examined for the presence of Ornithobacterium rhinotracheale using culture and enzyme-linked immunosorbent assay (ELISA). The identity was latter proved by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), western blot analysis, and polymerase chain reaction (PCR) assays. A total of 324 serum and 250 lung and trachea samples were collected from 10 commercially reared chicken flocks showing respiratory manifestations. The samples were obtained from different flocks. The causative agent (ORT) was isolated from trachea (1.5%) of five chickens and from both lung and trachea (0.4%) of only one chicken in the bacteriological examination of tissues. The presence of antibodies against ORT was detected in 33 (10.2%) of the 324 sera by ELISA. A 784 bp fragment of the 16S rRNA gene was amplified using specific primers in the PCR. All ORT isolates that were positive by culture were also detected to be positive by the PCR. SDS-PAGE protein profiles of whole cell extracts showed a high similarity for all the isolates with a major band of the molecular weight of 33 kDa (kiloDalton). Results of Western blot analysis indicate four antigenic fractions predominantly with molecular weights of 33, 42, 52 and 66 kDa.


1979 ◽  
Author(s):  
C.S. Cierniewski

Polypeptide chains Aα, Bβ and γ of porcine fibrinogen were isolated by preparative SDS polyacrylamide gel electrophoresis. Their purity was estimated by electrophoresis in polyacrylamide gel, amino acid composition and N-terminal amino acid analyses. Antisera to the pig polypeptide chains were produced in rabbits and they were employed in immunological comparative studies of porcine, bovine, human and duck fibrinogens. Antisera to the pig Aα chain showed in gel immunodiffusion and passive hemagglutination a strong cross-reaction with porcine, bovine and human fibrinogens. Antisera to the pig βB and γ chains cross-reacted only with porcine and bovine fibrinogens but they did not recognize human fibrinogen, The reaction of antiγ antisera was detectable only by passive hemagglutination test. In all cases antigenic similarity of the analyzed fibrinogens was mainly related to antigenic determinants of the Aα, Bβ and γ chains exposed on the intact fibrinogen molecule. None of analyzed antisera reacted with duck fibrinogen.


1980 ◽  
Vol 189 (3) ◽  
pp. 481-489 ◽  
Author(s):  
M O Longas ◽  
T H Finlay

1. Cleavage of the human antithrombin III–thrombin complex with [14C]methoxyamine hydrochloride results in inactive thrombin and 14C-labelled antithrombin III. 2. Discontinuous polyacrylamide-gel electrophoresis of the reduced dissociation fragments of the complex in the presence of sodium dodecyl sulphate reveals two antithrombin III bands that do not resolve during electrophoresis without reduction. The heavy band has the electrophoretic mobility of the native protein. The light band has an apparent mol.wt. that is approx. 4000 less than the molecular weight of native antithrombin III. 3. Treatment of the cleavage products of the complex with carboxypeptidase B yields 1 mumol of arginine, a new C-terminal amino acid, per mumol of thrombin dissociated. The results indicate that during formation of the antithrombin III–thrombin complex, the inhibitor is cleaved at an arginine–X bond; this arginine residue forms a carboxylic ester with the enzyme, while the excised polypeptide remains bound through a disulphide bridge(s).


Author(s):  
Rike Oktarianti ◽  
Rochmatul Nuryu Khasanah ◽  
Syubbanul Wathon ◽  
Kartika Senjarini

BackgroundDengue virus is transmitted by several species of Aedes mosquitoes, with Aedes albopictus as secondary vector. During blood feeding, these vectors inject saliva into the vertebrate hosts. The saliva contains anticoagulant, anti-inflammatory and immunogenic factors. The objective of this research was to detect immunogenic proteins from Ae.albopictus salivary glands reacting with sera of people living in dengue endemic areas. MethodsThe identification of immunogenic proteins of Ae. albopictus salivary gland used one-dimensional gel electrophoresis (sodium dodecyl sulfate polyacrylamide gel electrophoresis), and western blot analysis, respectively. To determine the immunogenic nature of the candidate proteins, the antigens from the salivary gland of Ae. albopictus were reacted with sera from healthy persons, dengue hemorrhagic fever (DHF) patients, and neonates, each of the groups comprising 10 samples. ResultsThe protein profiles of Ae. albopictus salivary glands showed 13 bands with molecular weights from 16 kDa up to 97 kDa, i.e. 16, 17, 26, 28, 31, 32, 45, 55, 60, 67, 73, 76, and 97 kDa. According to western blot analysis result, the 31 kDa proteins were recognized in all endemic population sera, both in DHF patients and healthy persons. In contrast, protein bands of 47 and 67 kDa were only recognized by the sera of DHF patients. ConclusionThree immunogenic proteins of 31, 47 and 67 kDa were detected from Ae. albopictus salivary glands. These immunogenic proteins may be developed as candidate biomarkers for bite exposure to Ae. albopictus and as vector-based DHF vaccines.


1989 ◽  
Vol 260 (3) ◽  
pp. 789-793 ◽  
Author(s):  
A Kispert ◽  
D J Meyer ◽  
E Lalor ◽  
B Coles ◽  
B Ketterer

A labile GSH transferase homodimer termed 11-11 was purified from rat testis by GSH-agarose affinity chromatography followed by anion-exchange f.p.l.c. The enzyme is unstable in the absence of thiol(s) and has relatively low affinity for both 1-chloro-2,4-dinitrobenzene (Km 4.4 mM) and GSH (Km(app.) 4.4mM). Its mobility on SDS/polyacrylamide-gel electrophoresis is slightly less than that of subunits 3 and 4 and its pI is 5.2. Subunit 11 has a blocked N-terminal amino acid residue, but after CNBr cleavage fragments accounting for 113 amino acid residues were sequenced and showed 65% homology with corresponding sequences in subunit 4, indicating that it is a member of the Mu family. GSH transferase 11 is a major isoenzyme in testis, epididymis, prostate and brain and present at lower concentrations in other tissues.


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