Expression of a heat stable phytase from Aspergillus fumigatus in tobacco (Nicotiana tabacum L. cv. NC89).
Indian J Biochem Biophys
;
2007 Feb; 44(1): 26-30
Artigo
em Inglês
| IMSEAR
| ID: sea-27077
ABSTRACT
Aspergillus fumigatus contains a heat-stable phytase of great potential. To determine whether this phytase could be expressed in plants as a functional enzyme, we introduced the phytase gene from A. fumigatus (fphyA) in tobacco (Nicotiana tabacum L. cv. NC89) by Agrobacterium-mediated transformation. Phytase expression was controlled by the cauliflower mosaic virus (CaMV) 35S promoter. Secretion of recombinant phytase (tfphyA) to the extracellular fluid was established by use of the signal sequence from tobacco calreticulin. Forty-one independent transgenic plants were generated. Single-copy line A was selected based on segregation of T1 seeds for kanamycin resistance, phytase expression and Southern blotting analysis for use in further study. After 4-weeks of plant growth, the phytase was accumulated in leaves up to 2.3% of total soluble protein. tfphyA was functional and shared similar profiles of pH, temperature and thermal stability to the same enzyme expressed in Pichia pastoris (pfphyA). The expressed enzyme had an apparent molecular mass of 63 kDa and showed maximum activity at pH 5.5, and temperature, 55 degrees C. It had a high thermostability and retained 28.7% of the initial activity even after incubation at 90 degrees C for 15 min. The above results showed that the thermostable A. fumigatus phytase could be expressed in tobacco as a functional enzyme and thus has the potential of overexpressing it in other crop plants also.
Texto completo:
DisponíveL
Índice:
IMSEAR (Sudeste Asiático)
Assunto principal:
Aspergillus fumigatus
/
Nicotiana
/
Estabilidade Enzimática
/
Proteínas Recombinantes
/
DNA Fúngico
/
Sequência de Bases
/
Expressão Gênica
/
Plantas Geneticamente Modificadas
/
6-Fitase
/
Genes Fúngicos
Idioma:
Inglês
Revista:
Indian J Biochem Biophys
Ano de publicação:
2007
Tipo de documento:
Artigo
Similares
MEDLINE
...
LILACS
LIS