Font Size: a A A

The Expression And Characteration Of Feruloyl Esterase In Penicillium Decumbens114-2

Posted on:2013-08-30Degree:MasterType:Thesis
Country:ChinaCandidate:M ShenFull Text:PDF
GTID:2230330374482901Subject:Bio-engineering
Abstract/Summary:PDF Full Text Request
Feruloyl esterase (FAE) is one type of hemicellulose degrading enzymes. FAE can hydrolyze the side chain on xylan in hemicelluloses, which cuts off the network structure between hemicelluloses and lignin. Therefore, the tight structure of lignocelluloses becomes so loose that the cellulases can attach to it more closely, which help to enhance lignocellulose hydrolyzation and increase the recovery of sugars from lignocellulose materials. FAE can also release phenolic compounds from lignocelluloses, such as ferulic acid (FA), p-coumarate acid, caffeic acid and sinapate acid. These phenolic compounds can be used in food, healthy, cosmetic, pharmaceutical field. Especially, FA has already been used widely in pharmaceutical, cosmetic, food, chemical industry by the virtues of its absorption on UV, anti-oxidative, anti-inflammation property.In the article, Penicillium decumbens114-2is an excellent strain with high yield of cellulases, which was screened from soil. The objective of the study is to obtain FAE through identifying, cloning and expressing feruloyl esterase gene (fae) in Penicillium decumbens114-2.Firstly, hypothetical feruloyl esterase genes in the known genome of Penicillium decumbens were identified by blasting protein sequence. Four candidate genes were got, which have a high similarity with feruloyl esterase on protein sequence.As a fungal expression system, Pichia pastoris GS115has its own advantages, such as strong introduce promoter, strong secretion peptide signal, high quantity of exogenous protein expression and low quantity of its own protein. It was found that gene06649can be expressed successfully on GS115. The protein was also analyzed.In order to avoid glycosylation and incorrect modification on exogenous protein, we use uracil defection mutant Ml2as the expression system. The recombination strain, Ml2-09278, Ml2-09178and Ml2-08709, were constructed and found that protein of09278was expressed successfully. By detection of enzyme activity and blasting protein sequence, it was presumed that the protein of09278was probably acetylxylan exterase.
Keywords/Search Tags:Feruloyl esterase gene, clone, express, Pichia pastoris, M12
PDF Full Text Request
Related items