Promoter mapping and transcriptional regulation of the iron-regulated Neisseria gonorrhoeae fbpA gene.
In this study, we have mapped the promoter region of the Neisseria gonorrhoeae ferric iron binding protein-encoding gene fbpA, determined the start point of transcription, and examined the accumulation of fbpA mRNA Primer extension analysis of the fbpA promoter region indicated a single transcriptional start site located 51 bp upstream of the ATG translational start site. Northern blot analysis with a 200-bp fbpA structural gene probe detected one transcript of 1.0 kb in RNAs extracted from gonococcal cultures grown under iron-restricted conditions; the 1.0-kb transcript was observed to accumulate at a steady rate throughout the growth cycle. In comparison, in cultures grown under iron-sufficient conditions, the intensity of the 1.0-kb transcript was reduced considerably. Isolation of total RNA from rifampin-treated cells indicated that the half-life of the 1.0-kb fbpA transcript in cells grown under iron-restricted conditions was 1.2 +/- 0.2 min, while that of the 1.0-kb fbpA transcript obtained from cultures grown under iron-sufficient conditions was 0.5 +/- 0.1 min. Taken together, our results indicate that the fbpA promoter is regulated by iron and that transcription and translation of FbpA are closely linked.
Forng
R Y
RY
Department of Microbiology and Immunology, Morehouse School of Medicine, Atlanta, Georgia 30310-1495, USA.
Ekechukwu
C R
CR
Subbarao
S
S
Morse
S A
SA
Genco
C A
CA
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics*; D001483:Base Sequence; D017931:DNA Primers; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial; D007501:Iron / Q000494:pharmacology*; D033862:Iron-Binding Proteins; D007700:Kinetics; D008969:Molecular Sequence Data; D009344:Neisseria gonorrhoeae / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D033902:Periplasmic Binding Proteins; D011401:Promoter Regions, Genetic; D012333:RNA, Messenger / Q000378:metabolism; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D017931:DNA Primers; D033862:Iron-Binding Proteins; D033902:Periplasmic Binding Proteins; D012333:RNA, Messenger; D007501:Iron