The tyrosyl-tRNA synthetase like gene located in the tyramine biosynthesis cluster of Enterococcus duransis transcriptionally regulated by tyrosine concentration and extracellular pH

BMC Microbiology

Research Article

Maria Cruz Martin¹  Beatriz Del-Río¹  Daniel M Linares¹  Miguel A Alvarez¹  Victor Ladero¹  Maria Fernández¹ 

[1] Instituto de Productos Lácteos de Asturias (IPLA-CSIC), Carretera de Infiesto s/n, 33300, Villaviciosa, Spain;

关键词: Biogenic Amine;    Tyramine;    Leader Region;    Tyrosine Concentration;    tyrS Gene;   

DOI  :  10.1186/1471-2180-12-23

 received in 2011-07-27, accepted in 2012-02-14,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundThe tyramine producer Enterococcus durans IPLA655 contains all the necessary genes for tyramine biosynthesis, grouped in the TDC cluster. This cluster includes tyrS, an aminoacyl-tRNA synthetase like gene.ResultsThis work shows that tyrS was maximally transcribed in absence of tyrosine at acidic pH, showing a greater than 10-fold induction in mRNA levels over levels occurring in presence of tyrosine. Mapping of the tyrS transcriptional start site revealed an unusually long untranslated leader region of 322 bp, which displays the typical features of the T box transcriptional attenuation mechanism. The tyrosine concentration regulation of tyrS was found to be mediated by a transcription antitermination system, whereas the specific induction at acidic pH was regulated at transcription initiation level.ConclusionsThe expression of the tyrS gene present in the TDC cluster of E. durans is transcriptionally regulated by tyrosine concentration and extracelular pH. The regulation is mediated by both an antitermination system and the promoter itself.

【 授权许可】

Unknown   
© Linares et al; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.