TITLE:
Induced Transcriptional Expression of Bacillus subtilis Amino Acid Permease yvbW in Response to Leucine Limitation
AUTHORS:
Sean M. Rollins
KEYWORDS:
T Box, Antitermination, Riboswitch, Amino Acid Permease, YvbW
JOURNAL NAME:
Advances in Microbiology,
Vol.4 No.8,
June
27,
2014
ABSTRACT:
T box sequences have
been identified upstream of a large number of uncharacterized genes such as
transporters in bacterial genomes. Expression of each T box family gene is
induced by limitation for a specific amino acid. T box family genes contain an
untranslated leader region containing a factor-independent transcriptional
terminator upstream of the structural genes. The anticodon of uncharged tRNA
base-pairs with the leader mRNA at a codon referred to as the specifier sequence,
inducing formation of an alternative antiterminator structure, allowing
expression of the structural genes. There
are several additional conserved primary sequence and secondary structural
elements. Analysis of these elements can be used to predict the identity of the
specifier codon and the amino acid signal.Bacillus subtilis hypothetical
amino acid permease, yvbW, was analyzed
as an example of this type of transcriptional regulatory prediction suggesting expression
in response to leucine limitation. Expression was induced up to 130-fold in
response to leucine limitation, utilizing a yvbW-lacZ transcriptional fusion. These data suggest that hypothetical amino acid
permease YvbW may participate in leucine metabolism. A yvbW knockout strain was generated, although the substrate
specificity for the putative amino acid permease was not identified.