Composition control of P3HB-co-3HHx through gradative expression of phaA and phaB genes in Pseudomonas sp. LFM461.

Author(s)

Lucas Garbini Cespedes

• Document type: Master's Dissertation
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Instituto de Ciências Biomédicas (ICB/SDI)
• Defense date: 2016-10-25

Examining board members

José Gregorio Cabrera Gomez; Welington Luiz de Araujo; Regina Lúcia Baldini

• Advisor: José Gregorio Cabrera Gomez

Abstract

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. (AU)

• FAPESP's process: 13/13495-8 - Control of P3HB-co-3HHx copolymer composition through gradative expression of phaA e phaB genes in Pseudomonas sp. LFM461 as host
• Grantee: Lucas Garbini Cespedes
• Support Opportunities: Scholarships in Brazil - Master