The small RNA Aar in Acinetobacter baylyi: a putative regulator of amino acid metabolism.
Small non-coding RNAs (sRNAs) are key players in prokaryotic metabolic circuits, allowing the cell to adapt to changing environmental conditions. Regulatory interference by sRNAs in cellular metabolism is often facilitated by the Sm-like protein Hfq. A search for novel sRNAs in A. baylyi intergenic regions was performed by a biocomputational screening. One candidate, Aar, encoded between trpS and sucD showed Hfq dependency in Northern blot analysis. Aar was expressed strongly during stationary growth phase in minimal medium; in contrast, in complex medium, strongest expression was in the exponential growth phase. Whereas over-expression of Aar in trans did not affect bacterial growth, seven mRNA targets predicted by two in silico approaches were upregulated in stationary growth phase. All seven mRNAs are involved in A. baylyi amino acid metabolism. A putative binding site for Lrp, the global regulator of branched-chain amino acids in E. coli, was observed within the aar gene. Both facts imply an Aar participation in amino acid metabolism.
Schilling
Dominik
D
Institute of Microbiology and Biotechnology, University of Ulm, 89069 Ulm, Germany. dominik.schilling@uniklinik-ulm.de
Findeiss
Sven
S
Richter
Andreas S
AS
Taylor
Jennifer A
JA
Gerischer
Ulrike
U
D000150:Acinetobacter / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism*; D001483:Base Sequence; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008969:Molecular Sequence Data; D009690:Nucleic Acid Conformation; D012329:RNA, Bacterial / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics; D022661:RNA, Untranslated / Q000235:genetics*; D015854:Up-Regulation
D000596:Amino Acids; D012329:RNA, Bacterial; D012333:RNA, Messenger; D022661:RNA, Untranslated