%0 Journal Article
%T The T box regulatory element controlling expression of the class I lysyl-tRNA synthetase of Bacillus cereus strain 14579 is functional and can be partially induced by reduced charging of asparaginyl-tRNAAsn
%A Niall Foy
%A Brian Jester
%A Gavin C Conant
%A Kevin M Devine
%J BMC Microbiology
%D 2010
%I BioMed Central
%R 10.1186/1471-2180-10-196
%X A global study of 891 completely sequenced bacterial genomes identified T box elements associated with control of LysRS expression in only four bacterial species: B. cereus, B. thuringiensis, Symbiobacterium thermophilum and Clostridium beijerinckii. Here we investigate the T box element found in the regulatory region of the lysK gene in B. cereus strain 14579. We show that this T box element is functional, responding in a canonical manner to an increased level of uncharged tRNALys but, unusually, also responding to an increased level of uncharged tRNAAsn. We also show that B. subtilis strains with T box regulated expression of the endogenous lysS or the heterologous lysK genes are viable.The T box element controlling lysK (encoding LysRS1) expression in B. cereus strain 14579 is functional, but unusually responds to depletion of charged tRNALys and tRNAAsn. This may have the advantage of making LysRS1 expression responsive to a wider range of nutritional stresses. The viability of B. subtilis strains with a single LysRS1 or LysRS2, whose expression is controlled by this T box element, makes the rarity of the occurrence of such control of LysRS expression puzzling.The aminoacyl tRNA synthetase (AARS) family of enzymes function to attach amino acids to their cognate tRNAs [1-3]. Each enzyme specifically charges a tRNA with its cognate amino acid in an energy requiring reaction that is executed with very high fidelity. However, despite all AARSs carrying out essentially the same reaction, the AARS family is subdivided into class I and class II enzymes that are structurally distinct and unrelated phylogenetically [for reviews see [3,4]]. This division of AARS into class I and class II enzymes is universal with each AARS being a member of one or other enzyme class in all living organisms. The lysyl-tRNA synthetase (LysRS) is an exception in that both class I (LysRS1) and class II (LysRS2) variants exist [5,6]. LysRS1 enzymes are found in Archaebacteria and in some eubac
%U http://www.biomedcentral.com/1471-2180/10/196