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typhoid purification

Muhammad Salman, Aamir Ali, Abdul Jabbar, Yasra Sarwar, Moazur Rahman, Mazhar Iqbal, Abdul Haque
Currently licensed typhoid vaccines are based on Vi capsular polysaccharides. Recent molecular reports from typhoid endemic countries state that Salmonella enterica serovar Typhi (S. Typhi) Vi negative strains occur naturally and cause typhoid fever which is indistinguishable from disease caused by Vi positive strains. Vaccine based on Vi polysaccharide may not protect patients if the invading S. Typhi are negative for Vi. The lipopolysaccharide (LPS) is an essential component of S. Typhi outer membrane in which O-specific polysaccharide (OSP) is a protective antigen and universal candidate for vaccine development...
2015: EXCLI journal
Neha Kothari, Kristopher R Genschmer, Sudeep Kothari, Jeong Ah Kim, David E Briles, Dong Kwon Rhee, Rodney Carbis
In the current study pneumococcal surface protein A (PspA) was conjugated to Vi capsular polysaccharide from Salmonella Typhi to make available a vaccine against typhoid fever that has the potential to also provide broad protection from Streptococcus pneumoniae. High yielding production processes were developed for the purification of PspAs from families 1 and 2. The purified PspAs were conjugated to Vi with high recovery of both Vi and PspA. The processes developed especially for PspA family 2 could readily be adapted for large scale production under cGMP conditions...
September 29, 2014: Vaccine
Chai Fung Chin, Boon Aun Teh, Amy Amilda Anthony, Ismail Aziah, Asma Ismail, Eugene Boon Beng Ong, Theam Soon Lim
In our earlier study, an immunoblot analysis using sera from febrile patients revealed that a 50-kDa band from an outer membrane protein fraction of Salmonella enterica serovar Typhi was specifically recognized only by typhoid sera and not sera from other febrile illnesses. Here, we investigated the identities of the proteins contained in the immunogenic 50-kDa band to pinpoint antigens responsible for its immunogenicity. We first used LC-MS/MS for protein identification, then used the online tool ANTIGENpro for antigenicity prediction and produced recombinant proteins of the lead antigens for validation in an enzyme-linked immunosorbent assay (ELISA)...
November 2014: Applied Biochemistry and Biotechnology
Maho Imanishi, Patience F Kweza, Rachel B Slayton, Tanaka Urayai, Odrie Ziro, Wellington Mushayi, Monica Francis-Chizororo, Lazarus R Kuonza, Tracy Ayers, Molly M Freeman, Emmaculate Govore, Clemence Duri, Prosper Chonzi, Sekesai Mtapuri-Zinyowera, Portia Manangazira, Peter H Kilmarx, Eric Mintz, Daniele Lantagne
Locally manufactured sodium hypochlorite (chlorine) solution has been sold in Zimbabwe since 2010. During October 1, 2011-April 30, 2012, 4,181 suspected and 52 confirmed cases of typhoid fever were identified in Harare. In response to this outbreak, chlorine tablets were distributed. To evaluate household water treatment uptake, we conducted a survey and water quality testing in 458 randomly selected households in two suburbs most affected by the outbreak. Although 75% of households were aware of chlorine solution and 85% received chlorine tablets, only 18% had reportedly treated stored water and had the recommended protective level of free chlorine residuals...
May 2014: American Journal of Tropical Medicine and Hygiene
S H Pakkanen, J M Kantele, A Kantele
There are no vaccines in clinical use against paratyphoid fever, caused by Salmonella Paratyphi A and B or, rarely, C. Oral Salmonella Typhi Ty21a typhoid vaccine elicits a significant cross-reactive immune response against S. Paratyphi A and B, and some reports suggest cross-protective efficacy against the disease. These findings are ascribed to the O-12 antigen shared between the strains. The Vi capsular polysaccharide vaccine has been shown to elicit antibodies reactive with O-9,12. Twenty-five volunteers immunized with the parenteral Vi vaccine (Typherix(®) ) were explored for plasmablasts cross-reactive with paratyphoid strains; the responses were compared to those in 25 age- and gender-matched volunteers immunized with Ty21a (Vivotif(®) )...
March 2014: Scandinavian Journal of Immunology
S Nishanth Kumar, C Mohandas, Bala Nambisan
The cell free culture filtrate of a Comamonas testosteroni associated with an Entomopathogenic nematode (EPN), Rhabditis (Oscheius) sp. exhibited promising antimicrobial activity. The ethyl acetate extract of the bacterial culture filtrate was purified by silica gel column chromatography to obtain five diketopiperazines or cyclic dipeptides (DKP 1-5). The structure and absolute stereochemistry of the compounds were determined based on extensive spectroscopic analyses (HR-MS, (1)HNMR, (13)CNMR, (1)H-(1)H COSY, (1)H-(13)C HMBC) and Marfey's method...
March 2014: Peptides
Sudeep Kothari, Neha Kothari, Jeong-Ah Kim, Eugene Lee, Yeon Kyung Yoon, So Jung An, Christopher Jones, Woo Seok Choe, Rodney Carbis
Vi capsular polysaccharide is the major component of Vi polysaccharide typhoid vaccines. Vi is synthesized during growth of Salmonella enterica subspecies enterica serovar Typhi and is released into the fermentation broth in large quantities. Along with the Vi considerable amounts of impurities consisting of bacterial protein, nucleic acid and lipopolysaccharide (LPS) as well as media components contaminate the fermentation broth. A purification method based on selective precipitation of Vi using the cationic detergent cetavlon was developed to separate impurities from Vi...
October 1, 2013: Vaccine
Eugene Boon Beng Ong, Amy Amilda Anthony, Aziah Ismail, Asma Ismail, Theam Soon Lim
The hemolysin (HlyE) protein of Salmonella enterica serovar Typhi was reported to be antigenic. This work describes the cloning, expression, and purification of a hexahistidine-tagged HlyE protein under native conditions. Immunoblot analysis and a competitive enzyme-linked immunosorbent assay using sera from typhoid patients showed the presence of HlyE-specific antibodies in circulation.
September 2013: Diagnostic Microbiology and Infectious Disease
Muhammad Shahbaz Aslam, Mohsina Akhter, Raheema Rasheed, Zahoor Qadir Samra, Iram Gull, Muhammad Amin Athar
BACKGROUND: Salmonella Typhi is a pathogenic bacterium that causes a number of infectious diseases such as gastroenteritis and typhoid fever. In this study, an antigenic (34 kDa) protein was identified, purified, and characterized from outer membrane of Salmonella typhi. METHODS: Immunoblot analysis was used to screen antigenic proteins from outer membrane of Salmonella Typhi. Proteins from outer membrane were isolated and resolved on SDS-PAGE. In immunoblot analysis, four proteins with the following molecular weights of 60 kDa, 54 kDa, 34 kDa, and 26 kDa were identified as highly antigenic against the serum of patients suffering from typhoid fever...
2012: Clinical Laboratory
H Ahmadi, B Tabaraie, S Maleknia, R Shapouri, M Nejati, F Pour Mirza Gholi, M Hedayati, M Sadati, S Zahednia, A Sharifat Salmani
Salmonella enterica subsp. Typhi (S. Typhi) Vi antigen capsular polysaccharide (Vi-CPS) is a licensed vaccine against typhoid fever. As there is no animal model for S. Typhi fever to evaluate the protective efficacy of the Vi-CPS vaccine, a serum bactericidal assay (SBA) is the recommended 'gold standard' to evaluate its potency. Vi-CPS was extracted from S. Typhi Ty6S (CSBPI-B191) using a modified Gotschlich method. Purified Vi-CPS (50 µg) was injected intramuscularly into three groups of five rabbits; group 2 received an additional booster dose of 50 µg Vi-CPS on day 15 and group 3 received two additional boosters on days 15 and 30...
February 2013: Journal of Medical Microbiology
Angela D Coulliette, Kyle S Enger, Mark H Weir, Joan B Rose
Unsafe drinking water continues to burden developing countries despite improvements in clean water delivery and sanitation, in response to Millennium Development Goal 7. Salmonella serotype Typhi and Vibrio cholerae bacteria can contaminate drinking water, causing waterborne typhoid fever and cholera, respectively. Household water treatment (HWT) systems are widely promoted to consumers in developing countries but it is difficult to establish their benefits to the population for specific disease reduction. This research uses a laboratory assessment of halogenated chlorine beads treating contaminated water to inform a quantitative microbial risk assessment (QMRA) of S...
June 2013: International Journal of Hygiene and Environmental Health
L Caetano M Antunes, Melody Wang, Sarah K Andersen, Rosana B R Ferreira, Reinhild Kappelhoff, Jun Han, Christoph H Borchers, B Brett Finlay
Infection with Salmonella enterica serovar Typhi in humans causes the life-threatening disease typhoid fever. In the laboratory, typhoid fever can be modeled through the inoculation of susceptible mice with Salmonella enterica serovar Typhimurium. Using this murine model, we previously characterized the interactions between Salmonella Typhimurium and host cells in the gallbladder and showed that this pathogen can successfully invade gallbladder epithelial cells and proliferate. Additionally, we showed that Salmonella Typhimurium can use bile phospholipids to grow at high rates...
May 2012: Journal of Bacteriology
F Micoli, S Rondini, I Pisoni, C Giannelli, V Di Cioccio, P Costantino, A Saul, L B Martin
A conjugate vaccine for Salmonella enterica serovar Typhi was produced by chemically linking Vi, purified from Citrobacter, to the non-toxic mutant diphtheria toxin CRM(197) via an adipic dihydrazide spacer using N-(3-Dimethylaminopropyl)-N'-ethylcarbodiimide coupling chemistry. The polysaccharide purification process was developed based on Vi precipitation from culture supernatant with cetyl trimethylammonium bromide (CTAB), solubilization of the CTA-polysaccharide salt with ethanol followed by exchange of the CTA(+) counter ion with Na(+)...
January 20, 2012: Vaccine
Patrice Francois, Manuela Tangomo, Jonathan Hibbs, Eve-Julie Bonetti, Catharina C Boehme, Tsugunori Notomi, Mark D Perkins, Jacques Schrenzel
We evaluated the robustness of loop-mediated isothermal amplification (LAMP) of DNA for bacterial diagnostic applications. Salmonella enterica serovar Typhi was used as the target organism and compared with a real-time quantitative PCR (qPCR) for testing assay performance and reproducibly, as well as the impact of pH and temperature stability. This isothermal amplification method appeared to be particularly robust across 2 pH units (7.3-9.3) and temperature values (57-67 °C). The detection limit was comparable to that observed using optimized home-brew qPCR assays...
June 2011: FEMS Immunology and Medical Microbiology
J Alan Roberson
The quality of drinking water in the United States has continued to improve over the past 40 years. The formation of the U.S. Environmental Protection Agency (USEPA) in 1971, the passage of the initial Safe Drinking Water Act (SDWA, PL 93-523) in 1974, and the passage of the 1996 SDWA Amendments (PL 104-208) represent significant progress in drinking water quality. While the widespread adoption of filtration and disinfection in the early 1900s virtually eliminated waterborne typhoid fever, some residual risks still remained 40 years ago...
January 1, 2011: Environmental Science & Technology
François Mansotte, Thomas Margueron, Dominique Maison
French Guyana is located in South America, and it is confronted with an endemic situation where waterborne diseases are widespread, especially among those 30,000 people without access to drinking water. In 2007, two notices of the French High Council for Public Health were issued, one concerning vaccination against typhoid and the other on conditions for improving water supply in Guyana. The latter served as a basis for proposing and implementing actions to "improve water quality for those who did not have access to it"...
March 2010: Santé Publique: Revue Multidisciplinaire Pour la Recherche et L'action
Duraipandian Thavaselvam, Ashu Kumar, Sapana Tiwari, Manvi Mishra, Archana Prakash
Brucellosis is a disease caused by Gram-negative, facultative, intracellular bacteria belonging to the genus Brucella. It is an emerging zoonosis, and an economically important infection of humans and livestock with a worldwide distribution. Human infection is known to occur through consumption of infected raw milk, milk products and undercooked or raw meat. Serodiagnosis of brucellosis is carried out by detection of antibodies generated against LPS or whole-cell bacterial extracts by ELISA or agglutination tests using colorimetry...
April 2010: Journal of Medical Microbiology
Verma Shailendra Kumar, Vandana Gautam, Konduru Balakrishna, Subodh Kumar
Porin proteins of Gram-negative bacteria are outer membrane proteins that act as receptors for bacteriophages and are involved in a variety of functions like solute transport, pathogenesis, and immunity. Salmonella enterica serovar Typhi (S. Typhi), a Gram-negative bacterium, is the causative agent of typhoid fever. Porins of S. Typhi have been shown to have a potential role in diagnostics and vaccination. In the present study, the major outer membrane proteins OmpF and OmpC from S. Typhi were cloned in pQE30UA vector and expressed in E...
September 2009: Journal of Microbiology and Biotechnology
Amit Arjyal, Anil Pandit
Enteric fever is systemic illness caused by Salmonella Typhi and Salmonella Paratyphi A, B and C. It is believed to be a readily treatable illness by many clinicians in the developing world where it is endemic; however, with the emergence of drug resistance to fluoroquinolones, treatment is becoming increasingly difficult. While drugs such as cefixime, previously believed to be effective, have been proven otherwise, new agents such as gatifloxacin and azithromycin have proven to be promising. Re-emergence of chloramphenicol sensitive strains in previously resistant areas points towards the concept of antibiotic recycling, preserving the use of older antibiotics...
2008: Journal of Infection in Developing Countries
J L Uma Maheswar Rao, T Satyanarayana
The purified alpha-amylase of Geobacillus thermoleovorans had a molecular mass of 26 kDa with a pI of 5.4, and it was optimally active at 100 degrees C and pH 8.0. The T 1/2 of alpha-amylase at 100 degrees C increased from 3.6 to 5.6 h in the presence of cholic acid. The activation energy and temperature quotient (Q 10) of the enzyme were 84.10 kJ/mol and 1.31, respectively. The activity of the enzyme was enhanced strongly by Co2+ and Fe2+; enhanced slightly by Ba2+, Mn2+, Ni2+, and Mg2+; inhibited strongly by Sn2+, Hg2+, and Pb2+, and inhibited slightly by EDTA, phenyl methyl sulfonyl fluoride, N-ethylmaleimide, and dithiothreitol...
August 2007: Applied Biochemistry and Biotechnology
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