• JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
  • JoomlaWorks Simple Image Rotator
 
  Bookmark and Share
 
 
Master's Dissertation
DOI
10.11606/D.87.2017.tde-16012017-152114
Document
Author
Full name
Lucas Garbini Cespedes
Institute/School/College
Knowledge Area
Date of Defense
Published
São Paulo, 2016
Supervisor
Committee
Gomez, José Gregorio Cabrera (President)
Araujo, Welington Luiz de
Baldini, Regina Lúcia
Title in Portuguese
Controle da composição do copolímero P3HB-co-3HHx por indução gradativa da expressão dos genes phaA e phaB em Pseudomonas sp. LFM461.
Keywords in Portuguese
Pseudomonas
Controle da composição
P3HB-co-3HHx
Polihidroxialcanoatos
Polímeros biodegradáveis
Abstract in Portuguese
Os copolímeros de 3-hidroxibutirato e 3-hidroxihexanoato (P3HB-co-3HHx) são da família dos polihidroxialcanoatos (PHA), materiais termoplásticos e biodegradáveis acumulados por bactérias a partir de fontes de carbono renováveis. O P3HB-co-3HHx desperta interesse industrial para frações de 3HHx menores que 20 mol%, assemelhando-se ao polietileno de baixa densidade. Neste projeto, criou-se um sistema genético para controlar a composição do copolímero P3HB-co-3HHx pela indução de genes da biossíntese de precursores 3HB. Baseado no promotor lac foram construídas cinco versões do plasmídeo de controle de copolímero (pCC) utilizando o promotor Lac. Porém, mesmo com a versão mais aprimorada, não foi possível o controle de composição de P3HB-co-3HHx em Pseudomonas sp. LFM461. Através de experimentos de atividade enzimática e RT-qPCR do cDNA do gene phaA e phaB, foi possível indicar que o problema está na impossibilidade do promotor Lac de promover expressão dos genes de biossíntese de 3HB presentes nos pCC.
Title in English
Composition control of P3HB-co-3HHx through gradative expression of phaA and phaB genes in Pseudomonas sp. LFM461.
Keywords in English
Pseudomonas
Biodegradable polymers
Composition control
P3HB-co-3HHx
Polyhydroxyalkanoates
Abstract in English
Polyhydroxyalkanoates (PHA) are polyesters material accumulated by bacteria which has thermoplastic and biodegradable proprieties and can be produced from renewable feedstocks. Copolymers of 3-hydroxybutirate and 3-hydroxyhexanoate (P3HB-co¬-3HHx) which contain less than 20mol% of 3HHx have being researched for its industrial proprieties. Recently, our laboratory has been researching a Pseudomonas sp. strain, LFM461, which can produce high 3HHx content when hosting PHA biosynthesis genes from Aeromonas. In this project, it was design a genetic system for control of P3HB-co-3HHX composition through induction of 3HB monomers biosynthesis. Thus, five versions of a copolymer control plasmid (pCC) was built based on Lac promoter. However, even through improvements on stability and expression profile of pCC it was not possible to stablish an assay of successful PHA composition control in Pseudomonas sp. LFM461. By enzymatic activity and RT-qPCR of cDNA experiments we have indications of problems of Lac promoter on driving the expression of 3HB genes in pCC.
 
WARNING - Viewing this document is conditioned on your acceptance of the following terms of use:
This document is only for private use for research and teaching activities. Reproduction for commercial use is forbidden. This rights cover the whole data about this document as well as its contents. Any uses or copies of this document in whole or in part must include the author's name.
Release Date
2019-01-16
Publishing Date
2017-01-16
 
WARNING: Learn what derived works are clicking here.
All rights of the thesis/dissertation are from the authors
CeTI-SC/STI
Digital Library of Theses and Dissertations of USP. Copyright © 2001-2020. All rights reserved.