Data/hora: 03/06/2024 07:52:09

Provedor de dados: 	58	
País: 	Brazil	
Título: 	Increase of stress resistance in Lactococcus lactis via a novel food-grade vector expressing a shsp gene from Streptococcus thermophilus	
Autores: 	Tian,Hongtao; Tan,Jianxin; Zhang,Lifang; Gu,Xinxi; Xu,Wentao; Guo,Xinghua; Luo,Yunbo.	
Data: 	2012-09-01	
Ano: 	2012	
Palavras-chave: 	Shsp gene; Streptococcus thermophilus; Lactococcus lactis; Food-grade vector; Stress resistance.	
Resumo: 	The effects of the expression of a small heat shock protein (shsp) gene from Streptococcus thermophilus on stress resistance in Lactococcus lactis under different environmental stresses were investigated in this study. pMG36e-shsp, an expression vector, was first constructed by inserting a shsp open reading frame (ORF) cloned from S. thermophilus strain St-QC into pMG36e. Then, a food-grade expression vector, pMG-shsp, was generated by deleting the erythromycin resistance gene from pMG36e-shsp. The transformation rate of pMG-shsp was comparable to that of pMG36e-shsp when each of these two vectors was introduced into L. lactis. These results demonstrated that the shsp ORF could successfully used as a food-grade selection marker in both pMG-shsp and pMG36e-shsp. Furthermore, the growth characteristics were almost the same between L. lactis ML23 transformants harboring pMG36e or pMG-shsp. The survival rate of L. lactis ML23 expressing the shsp ORF were increased to 0.032%, 0.006%, 0.0027%, 0.03%, and 0.16% under the following environmental stresses: heat, acid, ethanol, bile salt and H2O2, respectively. These results indicated that the expression of the shsp gene in the food-grade vector pMG-shsp conferred resistance to environmental stresses without affecting the growth characteristics of L. lactis ML23.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822012000300043	
Editor: 	Sociedade Brasileira de Microbiologia	
Relação: 	10.1590/S1517-83822012000300043	
Formato: 	text/html	
Fonte: 	Brazilian Journal of Microbiology  v.43 n.3 2012	
Fonte: 	info:eu-repo/semantics/openAccess