Thesis (Ph. D.)--University of Missouri--Columbia, 2000. / "December 2000." Typescript. Vita. Includes bibliographical references (leaves 120-131). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 2003. / "May 2003." Typescript. Vita. Includes bibliographical references (leaves 156-175).

Desulfurococcus fermentans is a hyperthermophilic archaeon growing optimally at 82??C. This microorganism is an obligate anaerobe with optimal growth pH of 6.0. It is capable of producing H2 as an end metabolic product using cellulose as growth substrate. The major goal of this study was to optimize the growth conditions for the production of H2 from various substrates such as cellulose, cellobiose, carboxymethyl cellulose (CMC), xylan, filter paper, avecil, starch and peptides. The highest cell density (2.83??108 cells/ml) was observed when yeast extract (0.2 g/L), starch (5 g/L) and xylan (4 g/L) were added to its growth media. The lowest generation time was shown to be 2.4 hours when yeast extract (0.2 g/L), starch (5 g/L) and cellobiose (4 g/L) were added to its growth medium. It was found that the growth of D. fermentans was obligately depended on the presence of yeast extract in the growth medium, and the H2 production was positively correlated to its growth. Cells of D. fermentans were cocci with diameters varying from 1 to 3 ??m. The largest cell size was observed using scanning electron microscopy when it grew in medium containing yeast extract (10 g/L) and starch (5 g/L). Maximum hydrogen production of 12% (v/v) was achieved when yeast extract (0.2 g/L), starch (5 g/L) and carboxymethyl cellulose (4 g/L) were added to the growth medium. Further studies are required to obtain the specific yield of H2 from various substrates through the quantification of both the consumption of substrates and the production of H2 by D. fermentans.

Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / "May 1996." Typescript. Vita. Includes bibliographical references (leaves 128-138). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves 156-175).

Thesis (Ph. D.)--University of Missouri--Columbia, 2000. / Typescript. Vita. Includes bibliographical references (leaves 120-131). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri--Columbia, 1996. / Typescript. Vita. Includes bibliographical references (leaves : 128-138). Also available on the Internet.

München, Techn. Univ., Diss., 2002.

Thesis (Ph. D.)--University of Missouri--Columbia, 1998. / "May 1998." Typescript. Vita. Includes bibliographical references (leaves 138-147). Also available on the Internet.

Submitted by Carla Ferreira (carlaferreira66@gmail.com) on 2014-07-31T12:23:26Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) HerminioSobrinho-2008 (1).PDF: 811492 bytes, checksum: 63a0aabcbb6458adb1051bc054066d08 (MD5) / Made available in DSpace on 2014-07-31T12:23:26Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) HerminioSobrinho-2008 (1).PDF: 811492 bytes, checksum: 63a0aabcbb6458adb1051bc054066d08 (MD5) Previous issue date: 2008 / Rheumatoid Arthritis (RA) and Systemic Lupus Erythematosus (SLE) are autoimmune diseases of unknown etiology. Some species of mycoplasmas cause arthritis in animals and humans, and their lipid-associated membrane proteins (LAMPs) and Mycoplasma arthritidis mitogen (MAM superantigen) are potent stimulators of the immune system. Thus, it has been proposed that mycoplasma can be involved in autoimmune-disease etiology. The objective of the present work was to detect antibodies to MAM and LAMPs of M. hominis and M. fermentans in the patient sera, and to characterize the profile of IgG antibodies reactivity with LAMPs in order to identify the major immunogenic mycoplasmal lipoproteins that could be involved in the etiopathogenesis of these autoimmune diseases. Serum samples were obtained from peripheral blood of female patients at the same age of healthy controls. Recombinant MAM (from M. arthrititidis), LAMPs of M. hominis PG21 and M. fermentans PG18 were used in Western blotting assays. Antibodies to MAM were detected in the patient and control sera (RA: 27.5% vs 18.8%; SLE: 21.7% vs 20.0%). At least 23 LAMPs were found in the preparations of M. hominis PG21 and of M. fermentans PG18 with molecular masses between 20 and 192 KDa. The sera of RA patients recognized a larger number of LAMPs of M. hominis PG21 and M. fermentans PG18 than the control sera (RA: 11 ± 4 vs controls: 7 ± 3, n = 35; p < 0,05). Most of the sera of RA patients presented strong reactivity with LAMPs of M. hominis PG21 (RA: 65.7% vs controls: 20%, p < 0.05). LAMPs of M. hominis PG21 with molecular masses < 49 and ? 20 KDa and LAMPs of M. fermentans PG18 < 102 and ? 58 were mainly recognized by IgG antibodies of RA patients. When comparing sera from SLE patients and controls there was detected no significant differences between the profiles of IgG reactivity. Therefore, M. hominis PG21 LAMPs (< 49 and ? 20 KDa) and M. fermentans PG18 LAMPs (< 102 and ? 58 KDa) are high immunogenic mycoplasmal antigens that can induce antibody cross reactivity with self antigen, contributing with the RA pathogenesis. / A artrite reumatóide (AR) e o lúpus eritematoso sistêmico (LES) são doenças autoimunes de etiologia desconhecida. Algumas espécies de micoplasmas causam artrite séptica em seres humanos, sendo estas bactérias fortes candidatos à etiopatogênese destas doenças. O superantígeno MAM é uma proteína secretada por Mycoplasma arthritidis, que juntamente com lipoproteínas (LAMPs) de M. hominis e M. fermentans, ativam as células do sistema imune e podem estar envolvidos na etiopatogenia da AR e do LES. O objetivo do presente trabalho foi detectar e caracterizar a resposta de anticorpos IgG contra superantígeno MAM e LAMPs de M. fermentans e M. hominis em soros de pacientes com AR ou LES, a fim de detectar as LAMPs mais imunogênicas candidatas a antígenos envolvidos na etiopatogenia destas doenças. Os pacientes com AR ou LES e os controles saudáveis eram indivíduos do sexo feminino e da mesma faixa etária. Foi usado MAM recombinante e LAMPs de M. hominis PG21 e M. fermentans PG18 extraídas com detergente Triton X-114, para avaliar o perfil de anticorpos IgG por meio da técnica de Western blotting. Anticorpos IgG anti-MAM foram detectados tanto nos soros de pacientes quanto nos dos controles (AR: 27,5% vs 18,8%; LES: 21,7% vs 20,0%). Foram detectadas pelo menos 23 LAMPs nas preparações de M. hominis PG21 e de M. fermentans PG18 com massas moleculares entre 20 e 192 KDa. Os soros de pacientes com AR reconheceram um maior número de LAMPs de M. hominis PG21 e de M. fermentans PG18 do que os soros controles (AR: 11 ± 4 vs controles: 7 ± 3, n = 35; p < 0,05). A maioria dos soros dos pacientes com AR apresentou forte reatividade com LAMPs de M. hominis PG21 (AR: 65,7% vs controles: 20%, p < 0,05). As LAMPs de M. hominis PG21 com massas moleculares <49 e ³ 20 KDa e de M. fermentans PG18 < 102 e ? 58 foram mais frequentemente reconhecidas por anticorpos IgG de soros de pacientes com AR do que por anticorpos dos soros controles. Não foram atestadas diferenças significantes entre os perfis de reatividade dos soros de pacientes com LES e controles, nem com relação ao número de LAMPs reconhecidas, nem com as diferentes faixas de massas moleculares das LAMPs. Portanto, as LAMPs de M. hominis (<49 e ³ 20 KDa) e M. fermentans (< 102 e ? 58) podem ser antígenos que induzem a produção de anticorpos que reagem cruzadamente com antígenos próprios, contribuindo para o processo da patogênese da AR.