Spelling suggestions: "subject:"galactosidase"" "subject:"bgalactosidase""
41 |
Produção enzimática de galactooligossacarídeos, a partir da lactose, por Pseudozyma tsukubaensis, Pichia kluyveri e Aspergillus oryzae / Enzymatic galactooligosaccharides production from lactose by Pseudozyma tsukubaensis, Pichia kluyveri and Aspergillus oryzaeFai, Ana Elizabeth Cavalcante 19 August 2018 (has links)
Orientador: Gláucia Maria Pastore / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-19T09:32:30Z (GMT). No. of bitstreams: 1
Fai_AnaElizabethCavalcante_D.pdf: 2054300 bytes, checksum: 82245332b8fef2de5e0f8a67509b102a (MD5)
Previous issue date: 2011 / Resumo: Galactooligossacarídeos (GOS) são prebióticos sintetizados via transgalactosilação enzimática da lactose e existem vários modos de se obter os produtos sintetizados nesta reação. Com o objetivo de se produzir GOS e hidrolisar lactose, ß-galactosidase de Aspergillus oryzae (Sigma®) foi covalentemente imobilizada em celite e em quitosana em pó ativada com glutaraldeído, sendo as propriedades destas avaliadas e comparadas em relação à enzima livre. Uma coluna de leito empacotado foi utilizada para a produção de GOS e hidrólise da lactose nos sistemas imobilizados. Os oligossacarídeos foram obtidos com um máximo de produtividade de 14,42 e 3,50 g/L.h, partindo de uma solução de lactose 40% (p/v), na coluna de leito empacotado com quitosana e celite, respectivamente. A hidrólise da lactose foi de 50,00 e 84,74% após 24 horas utilizando quitosana e celite como suportes enzimáticos, respectivamente. A fim de verificar a habilidade de síntese de GOS por Pichia kluyveri e Pseudozyma tsukubaensis, isoladas de pêssego (Prunus persica) e nectarina (Prunus persica var. nucipersica), respectivamente, utilizou-se células íntegras e viáveis para fermentar um meio de lactose a 40% (p/v). Rendimento máximo de 14,01 e 15,71% (p/p) de GOS foi obtido desta fermentação em 24 horas por P. kluyveri e P. tsukubaensis, respectivamente. Uma estratégia sequecial de dois planejamentos experimentais foi utilizada para otimização de rendimento de GOS e, sob as condições validadas, a atividade de transgalactosilação de P. tsukubaensis resultou em 28,35% (p/p) de rendimento de GOS em 24 horas, com uma produção de 73,71 g/L e aproximadamente 50% de hidrólise de lactose, a partir de uma concentração inicial de lactose de 26% (p/v). Foi proposto, ainda, um processo associado de biossurfactante/biomassa para síntese de GOS a partir da lactose. O biossurfactante sintetizado por P. tsukubaensis em manipueira foi otimizado utilizando planejamento experimental e análise de superfície de resposta, considerando como resposta a tensão superficial e a concentração de biomassa. A mínima tensão superficial e a máxima concentração de biomassa observada foram de 26,87 mN/m e 10,50 g/L, respectivamente. A atividade de trasgalactosilação da biomassa de P. tsukubaensis, nas condições otimizadas do processo, resultou em uma produção de 73,12 g/L e em rendimento de 18,28% (p/p) em 24 horas, a partir de 40% (p/v) de lactose / Abstract: Galactooligosaccharides (GOS) are prebiotics synthesized by enzymatic lactose transgalactosylation and there are many modes in which GOS producing reactions can be performed. In order to produce GOS and to hidrolise lactose Aspergillus oryzae ß-galactosidase (Sigma®) was covalently immobilized on celite and on glutaraldehyde-treated chitosan powder and its properties were evaluated and compared with those of free enzyme. A packed bed column with lactose recycle was employed for production of GOS and lactose hydrolysis by immobilized systems. Oligosaccharides were obtained with a maximum productivity of 14.42 and 3.50 g/L.h, from 40% (w/v) lactose solution, in packed bed column with enzyme on chitosan and celite, respectively. Lactose was 50.00 and 84.74% hydrolyzed after 24 hours using chitosan and celite as enzyme support, respectively. In order to verify the ability to synthesize GOS from Pichia kluyveri, isolated from peach (Prunus persica), and Pseudozyma tsukubaensis, isolated from nectarine (Prunus persica var. Nucipersica), living whole cells were used to ferment 40% (w/v) lactose solution. A maximum yield of 14.01 and 15.71% (w/w) GOS was obtained from the fermentation in 24 hours by P. kluyveri and P. tsukubaensis, respectively. A sequential strategy of two experimental designs was used to optimize GOS yield and under the validated conditions the transgalactosylation activity of P. tsukubaensis resulted in 28.35% (w/w) of GOS yield at 24h, with a production of 73.71 g/L and approximately 50% of lactose hydrolysis, from 26% (w/v) initial lactose concentration. An associated process for biosurfactant/biomass for GOS synthesis from lactose was subsequently proposed. Biosurfactant synthesis by P. tsukubaensis on cassava wastewater was optimized using experimental design on the response of surface tension and biomass concentration. The minimum surface tension and maximum biomass concentration predicted and experimentally confirmed were 26.87 mN/m and 10.50 g/L, respectively. The transgalactosylation activity of P. tsukubaensis biomass at optimized conditions from 40% (w/v) lactose resulted in a GOS production of 73.12 g/L and a yield of 18.28% (w/w) in 24 hours / Doutorado / Ciência de Alimentos / Doutor em Ciência de Alimentos
|
42 |
ß-galactosidase production by Kluyveromyces lactis in batch and continuous cultureRam, Elaine C. January 2011 (has links)
Submitted in fulfilment of the requirements of the Degree of Master of Technology: Biotechnology, Durban University of Technology, 2001. / Kluyveromyces sp. have adapted to existence in milk due to the evolution of
permeabilisation and hydrolytic systems that allow the utilisation of lactose, the sugar
most abundant in milk. Lactose hydrolysis, to equimolar units of glucose and galactose,
is facilitated by a glycoside hydrolase, i.e., β-galactosidase (EC 3.2.1.23). The versatility
of this enzyme allows its application in numerous industrial processes, amongst the most
significant of which, is its role in the alleviation of lactose intolerance, one of the most
prevalent digestive ailments, globally. In this study, β-galactosidase production by
Kluyveromyces lactis UOFS y-0939 was initially optimised in shake flask culture with
lactose as the sole carbon source, and thereafter, production was scaled up to batch, fedbatch
and continuous culture. Shake flask studies revealed optimum conditions of 30°C,
pH 7 and a 10% inoculum ratio, to be most favourable for β-galactosidase synthesis,
producing a maximum of 0.35 ± 0.05 U.ml-1 when cell lysates were prepared by
ultrasonication with glass beads. Batch cultivation in 28.2 and 40 g.L-1 lactose revealed
that elevated levels of the carbon source was not inhibitory to β-galactosidase production,
as maximum enzyme activities of 1.58 and 4.08 U.ml-1, respectively, were achieved. Cell
lysates prepared by ultrasonication and homogenisation were compared and homogenised
cell lysates were more than 3.5 fold higher that those prepared by ultrasonication, proving
homogenisation to be the superior method for cell disruption. The lactose feed rate of
4 g.L-1.h-1 in fed-batch culture operated at ± 20.4% DO, appeared to be inhibitory to
biomass production, as indicated by the lower biomass productivity in fed-batch
(0.82 g.L-1.h-1) than batch culture (1.27 g.L-1.h-1). Enzyme titres, however, were favoured
by the low DO levels as a maximum of 8.7 U.ml-1, 5.5 fold more than that obtained in
batch culture, was achieved, and would be expected to increase proportionally with the
biomass. Continuous culture operated at a dilution rate of 0.2 h-1, under strictly aerobic
conditions, revealed these conditions to be inhibitory to the lactose consumption rate,
however, the non-limiting lactose and high DO environment was favourable for
β-galactosidase synthesis, achieving an average of 8 ± 0.9 U.ml-1 in steady state.
|
43 |
Covalent immobilisation of β-Galactosidase from Escherichia coli to commercially available magnetic nanoparticles for the removal of lactose from milkPretorius, Chantelle 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2012. / ENGLISH ABSTRACT: ß-Galactosidase of Escherichia coli is the equivalent of lactase in humans and
has the ability to bind and hydrolyse lactose. Lactase de ciency is a common
phenomenon present in almost 70% of the world's population. This has
resulted in greater than before demands on the food processing industry to
develop a method that will allow for the hydrolysis of the disaccharide lactose
in milk but will also allow for the removal of the remaining active enzyme.
In this thesis, a new method, that is bio-speci c and well characterized
for the removal of lactose from a lactose containing solution, is described.
The E537D mutated version of ß-Galactosidase, which has a much lower
activity compared to the wildtype and is able to bio-speci cally bind lactose
for longer periods, was covalently immobilised to commercially available
magnetic nanoparticles (fl uidMAG-Amine) via two coupling strategies. Glutaraldehyde
is a cross-linking agent that reacts with amine groups, while N-
(3-Dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC) is a coupling
agent that activates carboxylic groups. These agents are widely used for
the coupling of biomolecules to solid supports.
The covalently coupled fluidMAG-E537D ß-Galactosidase particles were
characterized regarding retained enzymatic activity and ability to bind and
physically remove lactose from a lactose containing solution by applying an
external magnetic eld, after lactose binding, to the enzyme-particle complex
in solution.
Each component aimed at yielding this functionally immobilised enzyme
complex was studied and optimized to contribute to the development of this
novel technique, which is a ordable and simple, for the removal of lactose from
solution for the ultimate production of lactose free milk.
Results indicated the glutaraldehyde method of ß-Gal cross-linking to fluidMAG-Amine
to be the preferred strategy since it allowed an increased carrier capacity
of protein to the particles. The glutaraldehyde cross-linked protein also exhibited
a two-fold higher activity than the EDC coupled protein. Furthermore,
the glutaraldehyde cross-linked fluidMAG-E537D ß-Gal was able to physically
remove 34 % of the lactose from a 0.2 nmol/L lactose in solution. This, therefore,
con rmed the potential use of this novel technique in the food processing
industry. / AFRIKAANSE OPSOMMING: ß-Galaktosidase vanaf Escherichia coli is dieselfde as laktase in mense en beskik
oor die vermoë om laktose te bind en te hidroliseer. 'n Gebrek aan laktase
kom algemeen voor en ongeveer 70 % van die wêreldbevolking ly hieraan. Laasgenoemde
het daartoe gelei dat daar meer druk as vantevore op die voedselproduksie
industrie is om 'n metode te ontwikkel waarmee die hidrolise van
die disakkaried laktose in melk moontlik sal wees asook die verwydering van
die oorblywende aktiewe ensiem.
In hierdie tesis word 'n nuwe metode beskryf wat biospesi ek en goed gekarakteriseer
is vir die verwydering van laktose vanuit 'n laktose bevattende
oplossing. Die E537D gemuteerde weergawe van ß-Galaktosidase, wat beskik
oor 'n baie laer aktiwiteit as die wildetipe asook die vermoë om laktose biospesi
ek vir langer periodes te bind, is kovalent geïmmobiliseer op kommersieel
beskikbare magnetiese nanopartikels (fluidMAG-Amine) via twee koppelingsstrategieë. Glutaraldehied is 'n kruisbindingsagent wat met amino groepe reageer,
terwyl EDC 'n koppelingsagent is wat karboksie groepe aktiveer. Hierdie
agente word algemeen gebruik vir die binding van biomolekules aan soliede
matrikse.
Die kovalent gekoppelde fluidMAG-E537D ß-Galaktosidase partikels is gekarakteriseer
met betrekking tot behoue ensimatiese aktiwiteit en vermoë om
laktose te bind en sies te verwyder vanuit 'n oplossing wat laktose bevat deur
'n eksterne magneetveld op die ensiem-partikel kompleks in oplossing toe te
pas, nadat die binding van laktose plaasgevind het.
Elke komponent van hierdie funksioneel geïmmobiliseerde ensiemkomplekse
is ondersoek en geoptimaliseer met die doel om by te dra tot die ontwikkeling
van 'n nuwe tegniek wat bekostigbaar en eenvoudig is vir die verwydering van
laktose vanuit 'n oplossing vir die uiteindelike gebruik in die produksie van
laktose-vrye melk.
Resultate het getoon dat die glutaraldehied metode van ß-Gal kruisbinding
op fluidMAG-Amine verkies word aangesien dit 'n verhoogde draerkapasiteit
van proteïene op die partikels moontlik maak. Die glutaraldehied gekoppelde
proteïene beskik ook oor twee keer meer aktiwiteit as die EDC gekoppelde
proteïene. Die glutaraldehied gekoppelde fluidMAG-E537D ß -Gal kon 34 %
van die laktose teenwoordig in 'n 0.2 nmol/L laktose oplossing sies verwyder.
Hierdie het dus die potensiële gebruik van hierdie nuwe metode in die
voedselproduksie industrie bevestig.
|
44 |
Investigations of the Properties of Single Molecules of Escherichia coli β-galactosidase by Capillary Electrophoresis Laser-Induced FluorescenceJeremie, Crawford January 2016 (has links)
Single enzymes of E. coli sourced B-galactosidase were analysed in effort to expand the wealth of knowledge in the area of heterogeneity. Static and dynamic heterogeneity was studied with respect to catalytic rate, electrophoretic mobility, and heat shock protein chaperone systems. Temperature was found to be a contributing factor to the observed range of dynamic heterogeneity, with the range increasing with temperature. The inhibitor dissociation constant was determined to be a heterogeneous property of B-galactosidase. A novel assay was developed in which a single enzyme molecule was subjected to three separate solutions while the enzyme itself remained free in solution. / October 2016
|
45 |
Imobilização de β-galactosidase para obtenção de produtos lácteos com baixo teor de lactose / Imobilization of β-galactosidase to obtain dairy products with low teor of lactoseKlein, Manuela Poletto January 2010 (has links)
A β-galactosidase (E.C 3.2.1.23) é uma das enzimas mais empregadas na indústria de alimentos sendo utilizada na hidrólise da lactose. Neste trabalho foram utilizadas duas metodologias para imobilização desta enzima. Na primeira delas foi empregado como suporte um material híbrido à base de sílica que possui um grupo orgânico catiônico covalentemente ligado. A adsorção da enzima a este material apresentou eficiência que variou de 74 a 53% com o aumento da quantidade de enzima aplicada ao suporte. A baixa estabilidade térmica da enzima imobilizada obtida e as prováveis fracas interações envolvidas na sua adsorção a este suporte podem explicar o decréscimo de atividade observada durante as sucessivas bateladas de hidrólise da lactose. Na primeira batelada o grau de hidrólise foi de 90,9% e no final da última batelada (4ª), a enzima foi capaz de converter apenas 13% do substrato. A segunda metodologia utilizada foi imobilização covalente da enzima em um filme de celulose/líquido iônico modificado com uma poliamina e ativado com glutaraldeído. A presença da poliamina foi confirmada por análises de infravermelho. Após a imobilização, a enzima reteve 60% de sua atividade inicial. Bons resultados de hidrólise da lactose em batelada foram obtidos tanto a 7ºC como a 35ºC e foi possível reutilizar a enzima imobilizada por 16 ciclos consecutivos, a 7ºC, sem mudanças significativas na atividade enzimática. O valor de Km para a enzima imobilizada no material híbrido à base de sílica foi de 9,17 mM e para a enzima imobilizada nos filmes de celulose foi de 11,22 mM, ambos apresentaram um acréscimo quando comparados ao Km enzima livre (1,25 mM), devido à dificuldade de acesso do substrato ao sítio ativo da enzima. Não houve mudança no pH e temperatura ótimos da enzima imobilizada em relação à enzima livre em nenhum dos métodos testados. / β-galactosidase (E.C 3.2.1.23) is the most widely used enzymes in the food industry and its employed in the lactose hydrolysis process. In this study, two methodologies were used to test their immobilization. In the first, the enzyme was immobilized by adsorption in one silica based hybrid material that contains a cationic organic group covalently linked. The efficiency of immobilization showed a decrease of 74 to 53% by increasing the protein load applied to the support. The low thermo stability of the immobilized enzyme and the probable weak interactions involved in their adsorption, could explain the decrease in enzyme activity observed in the successive batch hydrolysis of lactose. In the first run, the degree of lactose hydrolysis was 90.9% and, at the end of the last run (4th), the enzyme was able to convert only 13% of the substrate. The second methodology used was the covalent immobilization of the enzyme on a cellulose/ionic liquid film, modified with a polyamine and activated using glutaraldehyde. The presence of a polyamine was confirmed by infrared analysis. After immobilization, the enzyme retained 60% of its initial activity. Highly efficient lactose conversion was achieved in a batch process at 7ºC and 35ºC and was possible to reuse the immobilized enzyme in 16 repeated cycles, at 7ºC, without any drastic decrease in enzyme activity. Km value for the immobilized enzyme in silica based hybrid material was 9.17 mM and for the enzyme immobilized in the film of cellulose/ionic liquid was 11.22 mM, both showing an increase compared with the Km value for free enzyme (1.25 mM), due to the difficulty of access of the substrate to the active sites of the enzyme. The immobilized enzyme did not show any changes in the optimal pH and temperature when compared to the free enzyme in both methods tested.
|
46 |
The α-galactosidase A deficient mouse as a model for Fabry disease and the effect of Gb3 depositions on peripheral nociceptive ion channel function / Die α-Galaktosidase A defiziente Maus als Modell für M. Fabry und der Effekt von Gb3-Ablagerungen auf die Funktion von peripheren nozizeptiven IonenkanälenHofmann, Lukas January 2018 (has links) (PDF)
Fabry disease (FD) is an X-linked lysosomal storage disorder with intracellular accumulation of globotriaosylceramide (Gb3) due to α-galactosidase A deficiency. We studied α-galactosidase A knockout mice (GLA KO) as a model for sensory disturbance and pain in FD.
Pain associated behavior of young (3 months) and old (≥18 months) GLA KO mice and wildtype (WT) littermates in an inflammatory and a neuropathic pain model was investigated. Furthermore, affective and cognitive behavior was assessed in the naïve state and in an inflammatory pain model. Gene and protein expression of pain associated ion channels and Gb3 accumulation in dorsal root ganglion (DRG) neurons was determined. We also performed patch clamp analysis on cultivated DRG neurons and human embryonic kidney 293 (HEK) cells expressing voltage-gated-sodium channel 1.7 (Nav1.7) as an in vitro model of FD. Intracellular Gb3 deposits were modulated using shRNA silencing of α-galactosidase A.
After intraplantar injection of complete Freund`s adjuvant (CFA) and chronic constriction injury (CCI) of the right sciatic nerve, old GLA KO mice did not develop heat and mechanical hypersensitivity in contrast to young GLA KO and old WT mice. Additionally, we found no relevant differences between genotypes and age-groups in affective and cognitive behavior in the naïve state and after CFA injection. Gene and protein expression analysis provided no explanation for the observed sensory impairment. However, cultured DRG neurons of old GLA KO mice revealed a marked decrease of sodium and Ih-currents compared to young GLA KO and old WT mice. DRG neurons of old GLA KO mice displayed substantial intracellular accumulation of Gb3 compared to young GLA KO and old WT mice. Similar to cultured neurons, sodium currents were also decreased in HEK cells treated with shRNA and consecutively increased intracellular Gb3 deposits compared to the control condition, but could be rescued by treatment with agalsidase-alpha.
Our study unveils that, similar to patients with FD, GLA KO mice display age-dependent sensory deficits. However, contrary to patients, GLA KO mice are also protected from hypersensitivity induced by inflammation and nerve lesion due to Gb3-dependent and reversible reduction of neuronal sodium- and Ih-currents. Our data provide evidence for direct Gb3-dependent ion channel impairment in sensory DRG neurons as a potential contributor to sensory dysfunction and pain in FD. / Bei Morbus Fabry (M. Fabry) handelt es sich um eine X-chromosomal vererbte, lysosomale Speichererkrankung mit intrazellulärer Akkumulation von Globo-triaosylceramid (Gb3) aufgrund eines α-Galaktosidase-A Mangels. Um die Pathophysiologie des M. Fabry aufzuklären, untersuchten wir die α-Galaktosidase-A defiziente Maus (GLA KO) als Modell für sensible Wahrnehmungsstörungen und Schmerz.
Das schmerzassoziierte Verhalten von jungen (3 Monate) und alten (≥18 Monate) GLA KO Mäusen und Wildtyp (WT) Wurfgeschwistern wurde in einem Entzündungs- und einem neuropathischen Schmerzmodell untersucht. Zudem wurde das affektive und kognitive Verhalten im naiven Zustand und in einem Entzündungsschmerzmodell betrachtet. Auf molekularer Ebene wurden die Gen- und Proteinexpression von schmerzassoziierten Ionenkanälen und die Gb3-Akkumulation in Spinalganglionneuronen (dorsal root ganglion, DRG) bestimmt. Darüber hinaus wurden kultivierte DRG Neurone und humane embryonale Nierenzellen 293 (HEK) mittels Patch-clamp-Analyse elektrophysiologisch untersucht. Die HEK Zellen dienten als in vitro Modell für M. Fabry und exprimierten stabil den spannungsgesteuerten Natriumkanal 1.7 (Nav1.7). Intrazelluläre Gb3 Ablagerungen wurden unter Verwendung von shRNA-Silencing der α-Galaktosidase A induziert.
Nach intraplantarer Injektion von complete Freund‘s Adjuvans (CFA) und chronic constriction injury (CCI) des rechten N. ischiadicus entwickelten alte GLA KO Mäuse, im Gegensatz zu jungen GLA KO und alten WT Mäusen, keine Überempfindlichkeit gegenüber Hitze und mechanischen Reizen. Darüber hinaus fanden wir keine relevanten Unterschiede zwischen Genotypen und Altersgruppen im affektiven und kognitiven Verhalten im naiven Zustand und nach Injektion von CFA. Gen- und Proteinexpressionsanalysen lieferten keine Erklärung für die sensible Beeinträchtigung. Jedoch zeigten kultivierte DRG Neurone von alten GLA KO Mäusen eine deutliche Abnahme der Natriumströme und der Ih Ströme im Vergleich zu jungen GLA KO und alten WT Mäusen. Außerdem wiesen DRG Neurone von alten GLA KO Mäusen eine verstärkte intrazelluläre Akkumulation von Gb3 im Vergleich zu jungen GLA KO und alten WT Mäusen auf. Ähnlich wie bei kultivierten Neuronen waren die Natriumströme in, mit shRNA behandelten HEK-Zellen, im Vergleich zu den Kontrollzellen ebenfalls verringert, konnten aber durch die Behandlung mit Agalsidase-alpha wiederhergestellt werden.
Unsere Studie zeigt, dass GLA KO Mäuse ähnlich wie Patienten mit M. Fabry altersabhängige sensible Veränderungen aufweisen. Im Gegensatz zu Patienten sind GLA KO Mäuse jedoch auch vor der Überempfindlichkeit geschützt, die durch eine Entzündung und Nervenläsion hervorgerufen wird. Unsere elektrophysiologischen Ergebnisse jedoch, deuten darauf hin, dass die Reduktion der Natrium- und Ih Ströme mit den veränderten Antworten auf die sensiblen Reize zusammenhängt. Diese Daten lassen auf eine Gb3 abhängige Ionenkanaldysfunktion in DRG Neuronen als potentiellen Faktor für sensible Fehlfunktion und Schmerz bei M. Fabry schließen.
|
47 |
Molecular pathogenesis, differential transcription of enzymes forming the lysosomal multienzymic complex and microsatellite based genotyping in canine GM1-gangliosidosis /Kreutzer, Robert. January 2008 (has links)
Zugl.: Hannover, Tierärztliche Hochsch., Diss., 2008.
|
48 |
A structural view of beta-galactosidase in actionJuers, Douglas H., January 2000 (has links) (PDF)
Thesis (Ph. D.)--University of Oregon, 2000. / Title from title screen. Paging within document: xii, 211 p. : ill. (some col.). Includes vita and abstract. Includes bibliographical references (p. 199-211).
|
49 |
A structural view of beta-galactosidase in action /Juers, Douglas H., January 2000 (has links)
Thesis (Ph. D.)--University of Oregon, 2000. / Includes vita and abstract. Includes bibliographical references (p. 199-211). Also available for download via the World Wide Web; free to University of Oregon users.
|
50 |
Avaliação genético-molecular de pacientes com doença de Fabry em hospital universitário de Salvador, BahiaMiguel, Diego Santana Chaves Geraldo January 2013 (has links)
Submitted by Antonio Geraldo Couto Barreto (ppgms@ufba.br) on 2013-11-04T14:01:42Z
No. of bitstreams: 1
PDF Final.pdf: 7736859 bytes, checksum: d029585d5add34bb5b7f5929fdd32069 (MD5) / Approved for entry into archive by Patricia Barroso (pbarroso@ufba.br) on 2013-11-04T17:16:06Z (GMT) No. of bitstreams: 1
PDF Final.pdf: 7736859 bytes, checksum: d029585d5add34bb5b7f5929fdd32069 (MD5) / Made available in DSpace on 2013-11-04T17:16:06Z (GMT). No. of bitstreams: 1
PDF Final.pdf: 7736859 bytes, checksum: d029585d5add34bb5b7f5929fdd32069 (MD5) / INTRODUÇÃO: A doença de Fabry (DF) é um erro inato do metabolismo dos
glicoesfingolípidos devido à deficiência da atividade da enzima α-galactosidase A;
é ligada ao cromossomo X e pacientes do sexo masculino geralmente
apresentam sintomas clássicos. Não há mutações comuns para este gene; mais
de 600 mutações já foram descritas no Human Gene Mutation Database.
OBJETIVO: O objetivo deste estudo é relatar todas as mutações e alterações
polimórficas observadas nos membros de cinco famílias com a doença de Fabry
do estado da Bahia-Brasil. MATERIAL E MÉTODOS: Um total de 48 pacientes
com suspeita de DF foi encaminhado para avaliação no Serviço de Genética
Médica do Hospital Universitário Professor Edgard Santos durante o período de
janeiro de 2009 a dezembro de 2011. Os 14 pacientes (06 homens/08 mulheres)
com diagnóstico de Doença de Fabry envolvidos neste trabalho são
acompanhados no Ambulatório de Erros Inatos do Metabolismo do Hospital
Professor Edgard Santos - Universidade Federal da Bahia. Eles pertencem a
cinco famílias (I, II, III, IV e V) não relacionadas. O gene GLA foi analisado através
da amplificação por PCR (reação em cadeia da polimerase) e sequenciamento de
ambas as cadeias de DNA de toda a região codificadora e de regiões nas junções
entre éxons e íntrons. Para todos os pacientes do sexo masculino e alguns do
sexo feminino foi realizada a medida da atividade da enzima α-galactosidase em
gota de sangue seca através da espectrometria de massa em tandem.
RESULTADOS: Quatro diferentes mutações causadoras de DF foram
encontradas e todas elas já foram relatadas previamente. Duas das cinco famílias
compartilham a mesma mutação (p.A156D). Nas famílias I e V (ambas com
mutação p.A156D) foi encontrado o mesmo polimorfismo (c.1000-22C> T), mas
uma outra diferente variação foi encontrada apenas na Família I. DISCUSSÃO:
Apesar do pequeno número de pacientes envolvidos neste estudo, este trabalho é
o mais completo em análise de polimorfismos do gene GLA, incluindo todos os
pacientes diagnosticados com a doença de Fabry do estado da Bahia-Brasil. A
análise de alterações polimórficas sugere que duas das cinco famílias têm uma
mesma origem ancestral. Mais estudos para avaliar esta hipótese estão
ocorrendo neste momento, através da análise de haplótipos.
|
Page generated in 0.0354 seconds