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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
371

Study of a valorisation process forbiomass industrial waste involvingacid cooking and enzymatichydrolysis

Brunet, Nicolas January 2020 (has links)
Lignocellulosic biomass has potential to chip in the chemical and biofuels supplies in future societies,even though lignocellulose is a recalcitrant structure that has to be treated in several steps. After theirproper life cycle, wood-derived materials such as particleboards have few outcomes today apart fromenergy recovery for heat production. Then, they may be used as lignocellulosic biomass sources in theproduction of molecules of interest. Fermentation from wood-derived monosaccharides imposespreliminary sugar retrieval, for instance through pre-treatment and enzymatic hydrolysis. This studyfocuses on the potential of particleboards waste for chemical and biofuel production by comparingsaccharification through simulated steam explosion pre-treatment and enzymatic hydrolysis betweennative and particleboard-derived wood, with an insight in subsequent fermentation by Saccharomycescerevisiae. Urea-Formaldehyde bound particleboard was investigated, as well as some aspects ofMelamine-Urea-Formaldehyde bound particleboard.Pre-treatment resulted in apparition of lignocellulosic degraded compounds in a much larger extent innative wood than in particleboard, which seemed to be only superficially impacted. Formation ofdegraded compounds from sugars – furfural and 5-hydroxymethylfurfural – was enhanced when pretreatmentwas prolonged. Removal of a substantial fraction of the adhesive contained in theparticleboards was observed, leading to comparable concentrations in free urea, its degradedproducts, and formaldehyde between native wood and particleboards during enzymatic hydrolysis.Enzymatic hydrolysis with cellulases and hemicellulases highlighted a critical role of pre-treatment toenhance final yields, both in native wood and in Urea-Formaldehyde particleboard. Adding 20 minutessteam-explosion type pre-treatment at 160 °C resulted in glucose yields increase from 18.5 % to 32.8% for native wood and from 15.6 % to 37.4 % for particleboard. Prolonging pre-treatment residencetime to 35 minutes resulted in much better glucose extraction for native wood but only slight progressfor the particleboard, as glucose yields reached 64.5 % and 41.1 % respectively. Maximalconcentrations achieved were 277 and 184 mg/gbiomass respectively.Fermentation brought to light high inhibition from both native wood and particleboard sources ofmedia, which were attributed to components or degraded products of lignocellulose that were notanalysed in this project. Ethanol was formed during fermentation, with reduced productivity butincreased yields as compared with the control sample. Inhibition was so strong that no difference couldbe given between native and particleboard wood. In this situation, no inhibition potential of resin orits degradation products could be proved. / Lignocellulosic biomassa har potential att bidra till kemikalier och biobränsletillförsel i framtidasamhällen, trots att lignocellulosa är en rekalcitrant struktur som måste behandlas i flera steg. Idagträmaterial som spånskivor bara används för energiåtervinning och värmeproduktion efter deraslivscykel. De kan därför användas som råvara för framställning av värdefulla molekyler.Fermenteringsprocesser behöver frisättningen av trä monosackarider genom förbehandlingsprocesseroch enzymatisk hydrolys. Studien fokuserar på potentialen för avfall från spånskivor för kemisk ochbiobränsleproduktion. Vi har jämfört sackarifiering mellan nativt trä och spånskivor genom simuleradångaxplosion och enzymatisk hydrolys, med en inblick i efterföljande fermentering av Saccharomycescerevisiae. Spånskivor bunden av urea-formaldehyd undersöktes, liksom vissa aspekter av spånskivorbundna med melamin-urea-formaldehyd.Förbehandlingen producerade högre koncentration av lignocellulosa nedbrytningsprodukter frånnativt trä jämfört med spånskivor. Bildningen av nedbrytningsprodukter från sockerarter - furfural och5-hydroxymethylfurfural - ökade med längre förbehandlingar. En väsentlig fraktion av limmet borttogsfrån spånskivorna, vilket ledde till jämförbara koncentrationer i fri urea, dess nedbrytningsprodukteroch formaldehyd mellan naturligt trä och spånskivor under enzymatisk hydrolys.Enzymatisk hydrolys med cellulaser och hemicellulaser avslöjade den kritiska rollen av förbehandlingför att förbättra utbytet, både i naturligt trä och i urea-formaldehyd spånskiva. Längre (20 minuter)ångexplosion vid 160° C resulterade i högre glukosutbytet (från 18,5% till 32,8% för naturligt trä ochfrån 15,6% till 37,4% för spånskivor). Förlängning av uppehållstiden före behandlingen till 35 minuterresulterade i mycket bättre glukosekstraktion för nativt trä (64,5%) men endast liten framsteg förspånskivan (41,1%). Detta resulterade i maximalt utbyte av 277 mg Glc/g biomassa och 184 mg Glc/ gbiomassa för nativt trä och spånskivor, respektive.Fermentering visade hög hämning från lignocellulosa nedbrytningsprodukter som inte analyserades iprojektet för både nativt trä och spånskällor för media. Etanol bildades under fermentering medreducerad produktivitet men ökade utbyten jämfört med kontrollprovet. Hämningen var så stark attingen skillnad kunde ges mellan naturligt trä och spånskivor. I denna situation kunde ingenhämningspotential för lim eller dess nedbrytningsprodukter bevisas.
372

Study of a valorisation process for biomass industrial waste involving acid cooking and enzymatic hydrolysis

Brunet, Nicolas January 2020 (has links)
Lignocellulosic biomass has potential to chip in the chemical and biofuels supplies in future societies,even though lignocellulose is a recalcitrant structure that has to be treated in several steps. After theirproper life cycle, wood-derived materials such as particleboards have few outcomes today apart fromenergy recovery for heat production. Then, they may be used as lignocellulosic biomass sources in theproduction of molecules of interest. Fermentation from wood-derived monosaccharides imposespreliminary sugar retrieval, for instance through pre-treatment and enzymatic hydrolysis. This studyfocuses on the potential of particleboards waste for chemical and biofuel production by comparingsaccharification through simulated steam explosion pre-treatment and enzymatic hydrolysis betweennative and particleboard-derived wood, with an insight in subsequent fermentation by Saccharomycescerevisiae. Urea-Formaldehyde bound particleboard was investigated, as well as some aspects ofMelamine-Urea-Formaldehyde bound particleboard. Pre-treatment resulted in apparition of lignocellulosic degraded compounds in a much larger extent innative wood than in particleboard, which seemed to be only superficially impacted. Formation ofdegraded compounds from sugars – furfural and 5-hydroxymethylfurfural – was enhanced when pretreatmentwas prolonged. Removal of a substantial fraction of the adhesive contained in theparticleboards was observed, leading to comparable concentrations in free urea, its degradedproducts, and formaldehyde between native wood and particleboards during enzymatic hydrolysis.Enzymatic hydrolysis with cellulases and hemicellulases highlighted a critical role of pre-treatment toenhance final yields, both in native wood and in Urea-Formaldehyde particleboard. Adding 20 minutessteam-explosion type pre-treatment at 160 °C resulted in glucose yields increase from 18.5 % to 32.8% for native wood and from 15.6 % to 37.4 % for particleboard. Prolonging pre-treatment residencetime to 35 minutes resulted in much better glucose extraction for native wood but only slight progressfor the particleboard, as glucose yields reached 64.5 % and 41.1 % respectively. Maximalconcentrations achieved were 277 and 184 mg/gbiomass respectively. Fermentation brought to light high inhibition from both native wood and particleboard sources ofmedia, which were attributed to components or degraded products of lignocellulose that were notanalysed in this project. Ethanol was formed during fermentation, with reduced productivity butincreased yields as compared with the control sample. Inhibition was so strong that no difference couldbe given between native and particleboard wood. In this situation, no inhibition potential of resin orits degradation products could be proved. / Lignocellulosic biomassa har potential att bidra till kemikalier och biobränsletillförsel i framtidasamhällen, trots att lignocellulosa är en rekalcitrant struktur som måste behandlas i flera steg. Idagträmaterial som spånskivor bara används för energiåtervinning och värmeproduktion efter deraslivscykel. De kan därför användas som råvara för framställning av värdefulla molekyler.Fermenteringsprocesser behöver frisättningen av trä monosackarider genom förbehandlingsprocesseroch enzymatisk hydrolys. Studien fokuserar på potentialen för avfall från spånskivor för kemisk ochbiobränsleproduktion. Vi har jämfört sackarifiering mellan nativt trä och spånskivor genom simuleradångaxplosion och enzymatisk hydrolys, med en inblick i efterföljande fermentering av Saccharomycescerevisiae. Spånskivor bunden av urea-formaldehyd undersöktes, liksom vissa aspekter av spånskivorbundna med melamin-urea-formaldehyd. Förbehandlingen producerade högre koncentration av lignocellulosa nedbrytningsprodukter frånnativt trä jämfört med spånskivor. Bildningen av nedbrytningsprodukter från sockerarter - furfural och5-hydroxymethylfurfural - ökade med längre förbehandlingar. En väsentlig fraktion av limmet borttogsfrån spånskivorna, vilket ledde till jämförbara koncentrationer i fri urea, dess nedbrytningsprodukteroch formaldehyd mellan naturligt trä och spånskivor under enzymatisk hydrolys. Enzymatisk hydrolys med cellulaser och hemicellulaser avslöjade den kritiska rollen av förbehandlingför att förbättra utbytet, både i naturligt trä och i urea-formaldehyd spånskiva. Längre (20 minuter)ångexplosion vid 160° C resulterade i högre glukosutbytet (från 18,5% till 32,8% för naturligt trä ochfrån 15,6% till 37,4% för spånskivor). Förlängning av uppehållstiden före behandlingen till 35 minuterresulterade i mycket bättre glukosekstraktion för nativt trä (64,5%) men endast liten framsteg förspånskivan (41,1%). Detta resulterade i maximalt utbyte av 277 mg Glc/g biomassa och 184 mg Glc/ gbiomassa för nativt trä och spånskivor, respektive. Fermentering visade hög hämning från lignocellulosa nedbrytningsprodukter som inte analyserades iprojektet för både nativt trä och spånskällor för media. Etanol bildades under fermentering medreducerad produktivitet men ökade utbyten jämfört med kontrollprovet. Hämningen var så stark attingen skillnad kunde ges mellan naturligt trä och spånskivor. I denna situation kunde ingenhämningspotential för lim eller dess nedbrytningsprodukter bevisas.
373

Chlamydia trachomatis Transformants Show a Significant Reduction in Rates of Invasion upon Removal of Key Tarp Domains

Parrett, Christopher 01 January 2016 (has links)
Chlamydia trachomatis is an obligate, intracellular bacterium which is known to cause multiple human infections including nongonococcal urethritis (serovars D-K), lymphogranuloma venereum (serovars L1, L2, L3) and trachoma (serovars A-C). The infectious form of the bacterium, called the elementary body (EB), harbors a type III secreted effector known as Tarp (translocated actin recruiting phosphoprotein) which is a candidate virulence factor and is hypothesized to play a role in C. trachomatis' ability to invade and grow within epithelial cells in a human host. C. trachomatis L2 Tarp harbors five unique protein domains which include the Phosphorylation Domain, the Proline Rich Domain, the Actin Binding Domain, and two F-Actin Binding Domains. Tarp has been biochemically characterized in vitro, but it has yet to be characterized in vivo due to a lack of genetic tools in C. trachomatis. Through the recent generation of a chlamydial transformation system, we have created transformants which express epitope tagged wild type or mutant Tarp effectors. In this thesis, C. trachomatis transformants expressing Tarp lacking one of the five biochemically defined protein domains were used to examine both bacterial invasion and bacterial development within mammalian host cells. Our results demonstrate that those EBs which harbor mutant Tarp missing either its Phosphorylation Domain or its Actin Binding Domain were less capable of host cell invasion. However, these transformants, once internalized, were capable of normal development when compared to wild type C. trachomatis or C. trachomatis harboring an epitope tagged wild type Tarp effector. These results suggest that transformant expressed Tarp lacking the Phosphorylation Domain or Actin Binding Domain may be acting as a dominant-negative effector protein. Ultimately, these results support the hypothesis that Tarp is a virulence factor for Chlamydia trachomatis. Furthermore, this data indicates that through the manipulation of the Tarp effector, C. trachomatis pathogenesis may be attenuated.
374

Synthesis and Characterization of Antimicrobial Non-Color Forming Silica-Silver Nanocomposite

Bazata, Joshua 01 January 2015 (has links)
Silver has been utilized for its antimicrobial properties for thousands of years in a variety of fields, extending the shelf life of food and water, rendering eating utensils sanitary, and more recently in biomedical applications such as silver based antiseptic creams. While effective as an antimicrobial agent at very low concentrations (µg/mL), silver imparts a strong color to objects it is incorporated into, due to its high plasmonic efficiency. The goal of this study was to determine if incorporating silver nanoparticles into a silica matrix could reduce or eliminate the plasmonic signal, while retaining the antimicrobial effects of the silver nanoparticles. Citrate capped silver nanoparticles (AgNP) were synthesized using a borohydride reduction method as outlined by Zheng et. al., and incorporated into silica nanoparticles using a method adapted from Fleger et. al. To test the antimicrobial efficacy of these synthesized silica coated silver nanoparticles (SiAgNP), minimum inhibitory concentration testing at three time points, 1, 4, and 8 hours, was carried out against E. coli and S. aureus using broth microdilution and Alamar Blue as an indicator of microbial growth. Efficacy was judged against uncoated AgNP and aqueous silver nitrate (AgNO3) solutions at equivalent Ag concentrations. Silica nanoparticles (SiNP) were utilized as a negative control. Further antimicrobial characterization using a bacterial viability assay revealed a time dependent killing trend in the SiAgNP, suggesting a controlled release of Ag+ from within the silica matrix. Efficacy of the SiAgNP was determined to fall between the most effective antimicrobial form of silver tested, AgNO3, and least effective, AgNP. However, the SiAgNP material exhibited no visible plasmon peak when UV-Visible spectrophotometric readings were taken, as well as remaining colorless when coated onto a ceramic substrate. Zeta potential revealed a high degree of colloidal stability of the SiAgNP. TEM imaging studies were carried out, verifying the presence of Ag within and on the silica nanoparticles, as well as the crystalline structure of the uncoated AgNP. It was determined that coating AgNP synthesized through borohydride reduction with silica through a Stöber synthesis mechanism yields a material with enhanced antimicrobial effects compared to AgNP, but with no detectable plasmon signal, effectively producing a non-color forming silver based antimicrobial.
375

Synthesis and Characterization of Core-Shell Zinc Silica Nanoparticles and Zinc Silica Nanogels for Agricultural Applications.

Berroth, Megan 01 January 2015 (has links)
Plant pathogens are a serious problem facing the agricultural industry today. Current methodologies use copper based biocides as the main form of defense. Unfortunately this can lead to damaging environmental effects and increased rates of antimicrobial resistance. In this study, antimicrobial activity of multiple alternative zinc-based nanoformulations were tested against three important plant pathogens: Xanthomonas alfalfae, Pseudomonas syringae, and Clavobacter michiganensis. Xanthomonas sub species cause Citrus canker, a devastating disease that affects millions of citrus trees worldwide while the latter two affect tomato crops. Materials synthesis was completed and the resulting nanoformulations were characterized by Atomic Absorption Spectroscopy, Scanning Electron Microscopy, High Resolution Transmission Electron Microscopy, and X-Ray Photoelectron Spectroscopy. The antimicrobial efficacy of the newly synthesized formulas and two commercially available products, Kocide 3000 (DuPont) and Nordox (Brandt), were determined by Minimum Inhibitory Concentration Assays followed by Bacterial Viability Assays. The subsequent data demonstrated a marketed difference in the way the antimicrobial agents acted upon the bacterial species. The core-shell zinc silica nanoparticles (C-SZnSiNP) proved to be ineffective, while the zinc silica nanogel (ZnSiNG) was as successful at killing the bacteria as the commercial products. This shows promise for a new alternative material with zinc at the forefront of the fight against plant pathogens.
376

Chaperonin Containing TCP1 (CCT) as a Target for Cancer Therapy

Carr, Ana 01 January 2017 (has links)
Treatments for aggressive cancers like triple negative breast cancer (TNBC) and small-cell lung cancer (SCLC) have not improved and remain associated with debilitating side effects. There is an unmet medical need for better, druggable targets and improved therapeutics. To this end, we investigated the role of Chaperonin-Containing TCP1 (CCT), an evolutionarily conserved protein-folding complex composed of eight subunits (CCT1-8), in oncogenesis. Our laboratory was the first to report that the CCT2 subunit is highly expressed in breast cancer and could be therapeutically targeted. To determine whether CCT is a marker of disease progression in other cancers, we analyzed CCT2 gene expression in liver, prostate and lung cancer, using publicly available genetic databases, and confirmed findings by assessing CCT2 and client proteins, like STAT3, in tumor tissues by immunohistochemistry. We found that CCT2 was high in all cancers, especially SCLC, and correlated with decreased patient survival. We tested CT20p, the peptide therapeutic developed by our laboratory to inhibit CCT, on SCLC and primary lung cells, finding that CT20p was only cytotoxic to SCLC cells. Since SCLC currently lacks targeted therapeutics, our work yielded a new targeted agent that could improve lung cancer mortality. To establish a mechanism of action for CT20p, we partially knocked out CCT2 in TNBC cells, which decreased tumorigenicity in mice and reduced levels of essential proteins like STAT3. To confirm, we overexpressed CCT2 in non-tumorigenic cells and conferred tumor-like characteristics such as increased migration and elevated STAT3. These studies positioned us to develop and validate a strategy for discovery of new small molecule inhibitors of CCT. We thus advanced the field of cancer research by demonstrating that CCT could have diagnostic potential for cancers, such as SCLC and TNBC, that are a significant cause of human death and showed that targeting CCT is a promising therapeutic approach.
377

Assessment of Tattoo and Silicone Wounds in Terms of Time of Treatment and Perceived Treatment Quality

Pettitt, M 01 January 2017 (has links)
At the point of injury, critical medical tasks include locating and identifying an injury as well as applying the appropriate initial care. Over the past decade, to increase the fidelity of wound representation and ultimately the quality of medical care, a considerable amount of research and development has occurred to improve simulated wounds during training, primarily at the point of injury. As material and techniques mature and as more relevant data is collected on tissue properties, examining what fidelity is required for training at the point of injury is crucial. The main objective of this effort was to assess a three dimensional silicone wound versus a two dimensional tattoo wound for training and to examine differences in user perceptions and treatment time. This was accomplished with a test population of 158 City of Orlando Fire Department First Responders which were randomly assigned to each group (three dimensional silicone wound group versus a two dimensional tattoo wound group). The data analyses incorporated the use of non-parametric statistics (Mann-Whitney U Test) to compare the differences between the two groups on depth perception, sense of urgency, immersion, and time on task. Other factors that were examined included the costs for the average tattoo wound and silicone wound as well as the number of uses before the synthetic wound is visibly damaged. The data results indicated that at the point of injury, there were relatively few statistically significant differences in the survey data or time on task between the silicone and tattoo wounds. Additionally, the cost analysis revealed that the silicone wound is significantly more expensive than the tattoo wound. Supporting the military and civilian first responder communities, the results of this study provides statistically reliable data on the use of trauma tattoos as a tool for mastering point of injury treatment during training exercises.
378

Role of Mycobacterium avium paratuberculosis (MAP) and TNFSF15 SNPs on TL1A in CD

Hassouneh, Sayf Al-Deen 01 January 2018 (has links)
Tumor Necrosis Factor-Like Ligand 1a (TL1A) is a cytokine encoded by Tumor Necrosis Factor Super Family 15 gene (TNFSF15) gene mostly in endothelial cells which binds to T-cells and foments the production of pro-inflammatory cytokines including TNF-α, IL-6, IL-1b, IFN- γ and IL-13. TL1A level is elevated in inflammatory diseases including Crohn's Disease (CD). Although Single Nucleotide Polymorphisms (SNPs) in TNFSF15 have been reported in CD, no studies have investigated the effect of these SNPs on TL1A, inflammation, and susceptibility to Mycobacterium avium subspecies paratuberculosis (MAP) infection. MAP is a strong candidate in CD pathogenesis. This study is designed to elucidate the combined effect of MAP and SNPs in TNFSF15 (rs4263839, rs7848647, rs6478108, or rs6478109) on TL1A secretion and downstream effect on pro-inflammatory cytokines. Peripheral blood from CD and healthy subjects was analyzed for MAP DNA, TNFSF15 genotyping, circulating TL1A level, and IFN- γ and TNF-α gene expression. Our data is first to report that rs4263839, rs7848647, rs6478108, and rs6478109 in TNFSF15 resulted in increase in circulating TL1A level in healthy and CD samples. Specifically, in CD samples with rs7848647, the average TL1A level was 146.9 pg/mL ± 124.5 compared 62.4 pg/mL ± 82.8 in normal samples. Similarly, TL1A level in CD samples with rs6478109 was 141.9 pg/mL ± 127.7 compared to 71.5 pg/mL ± 88.4 in normal samples (p < 0.05). All 4 SNPs resulted in significant elevation in TL1A level in healthy samples (p < 0.05). Moreover, IFN-γ expression was significantly higher, by approximately 1.6-fold in CD patients with SNPs relative to CD patients with no SNPs (p < 0.05). Interestingly, SNPs in TNFS15 had no significant effect on TNF-α expression. MAP was detected in the blood of 63% of CD compared to 6% healthy subjects (p < .001). The data did not support a correlation between MAP presence and circulating TL1A levels, and no correlation between SNPs in TNSF15 and MAP susceptibility. This study strongly suggests, that SNPs in TNFSF15 increase TL1A levels and may be a contributory factor to the inflammation experienced by CD patients. Over all, the study emphasizes the need for a pharmacogenomic approach in treatment delivery for patients with CD by using TNFSF15 SNPs to identify patients that would benefit from biologics targeting TL1A rather than TNF-α for more efficacious treatment regiments for CD patients.
379

Phenotypic and Molecular Characterization of the Emergent Marine Pathogen Vibrio vulnificus

Jayakumar, Jane Maureen 01 January 2019 (has links)
Vibrio vulnificus, a natural inhabitant of brackish and estuarine environments, is a fatal opportunistic human pathogen with a mortality rate of over 50%. Unlike for other pathogenic Vibrio species, and despite its high mortality rate, there is no conclusive approach to indicate the pathogenic potential of V. vulnificus isolates from the environment. To this day, a single gene encoding a hemolysin, vvh, has been used to detect V. vulnificus, and one phenotype - indole production, has been used to assess the pathogenic potential and classification of a given strain. In this study, we use genomic-based approaches to identify distinct phenotypes that can characterize V. vulnificus strains with highest pathogenic potential (cluster 1 – C1), and to determine novel genes that can be used to accurately detect and identify V. vulnificus strains from natural reservoirs. Our phenotypic analyses indicate that strains from C1 utilize a more diverse range of carbon sources compared to strains less likely to emerge as pathogenic (cluster 2 – C2). We found that C1 and C2 prefer to inhabit different niches leading to behavioral separation. Physiological adaptations like motility in the presence of mucin and growth at different salinities indicate markedly different lifestyles for these clusters. These phenotypes can thus be used as markers to predict the pathogenic potential of unknown V. vulnificus isolates from the environment based on their clusters. Furthermore, we identified six candidate genes that can distinctly discriminate between the two clusters and are more sensitive in detecting V. vulnificus compared to existing typing techniques. The high degree of resolution offered by this simple, reproducible approach can thus be used to identify V. vulnificus strains from natural reservoirs, as validated in our study using environmental isolates from oysters and water.
380

Stable Expression Of Tuberculosis Vaccine Antigen In Lettuce Chloroplasts

Lakshmi, Priya Saikumar 01 January 2011 (has links)
Tuberculosis (TB) is caused by Mycobacterium tuberculosis and is one of the leading reasons of death by an infectious bacterial pathogen. The development of TB vaccines has been recognized as a major public health priority by the World Health Organization. In this study, a potential candidate antigen, ESAT-6 (6 kDa early secretory antigenic target) was fused with cholera toxin B subunit (CTB). Transplastomic lettuce plants were generated expressing these fusion proteins. Site-specific transgene integration into the chloroplast genome was confirmed by polymerase chain reaction and Southern blot analysis. In transplastomic leaves, expression levels of fusion protein (CTB-ESAT6) varied depending upon the developmental stage and time of leaf harvest with highestlevel of accumulation in mature leaves harvested at 6PM. Transplastomic CTB-ESAT6 lettuce plants accumulated up to 0.75% of total leaf protein. Lyophilization increased CTB-ESAT6 protein content per gram of leaf material by 22 fold. Western blot analysis of lyophilized lettuce leaves showed that the CTB-ESAT6 fusion protein was stable and can be stored for prolonged period at RT. Hemolysis assay with purified CTB-ESAT6 protein showed partial hemolysis of red blood cells and confirmed functionality of ESAT-6 antigen. GM-1 binding assay demonstrated that the CTB-ESAT6 fusion protein formed pentamers to interact with GM1 ganglioside receptor. The expression of functional Mycobacterium tuberculosis antigens fused to CTB in transplastomic plants should facilitate development of a cost-effective and orally deliverable TB vaccine with potential for long term storage at room temperature

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