ESCHERICHIA-COLI LEUCINE-RESPONSIVE REGULATORY PROTEIN (LRP) CONTROLS LYSYL-TRANSFER RNA-SYNTHETASE EXPRESSION

作者：GAZEAU M; DELORT F; DESSEN P; BLANQUET S; PLATEAU P

来源：FEBS Letters, 1992, 300(3): 254-258.

DOI：10.1016/0014-5793(92)80857-D

• LYSYL-TRANSFER RNA SYNTHETASE
• LEUCINE-RESPONSIVE REGULATORY PROTEIN
• LYSU
• LRP
• LEUCINE
• ESCHERICHIA-COLI

Using random Tn10 insertion mutagenesis, we isolated an Escherichia coli mutant strain affected in the regulation of lysU, the gene encoding the inducible form of lysyl-tRNA synthetase. The transposon giving rise to the altered expression of lysU was found inserted within lrp. The latter gene codes for the leucine-responsive regulatory protein (Lrp) which mediates a global response of the bacterium to leucine. An involvement of Lrp in the regulation of lysU was searched for by using a lysU-lacZ operon fusion. The following conclusions were reached: (i) inactivation of lrp causes an increased activity of the lysU promoter, whatever the growth conditions assayed, (ii) insertion of a wild-type lrp gene into a multi-copy plasmid significantly reduces lysU expression, and (iii) sensitivity of the lysU promoter to the presence of leucine in the growth medium is abolished in the lrp context.

• 出版日期1992-4-6