Targeted decay of a regulatory small RNA by an adaptor protein for RNase E and counteraction by an anti-adaptor RNA.

Bacterial small RNAs (sRNAs) are well established to regulate diverse cellular processes, but how they themselves are regulated is less understood. Recently, we identified a regulatory circuit wherein the GlmY and GlmZ sRNAs of Escherichia coli act hierarchically to activate mRNA glmS, which encodes glucosamine-6-phosphate (GlcN6P) synthase. Although the two sRNAs are highly similar, only GlmZ is a direct activator that base-pairs with the glmS mRNA, aided by protein Hfq.

Common and divergent features in transcriptional control of the homologous small RNAs GlmY and GlmZ in Enterobacteriaceae.

Small RNAs GlmY and GlmZ compose a cascade that feedback-regulates synthesis of enzyme GlmS in Enterobacteriaceae. Here, we analyzed the transcriptional regulation of glmY/glmZ from Yersinia pseudotuberculosis, Salmonella typhimurium and Escherichia coli, as representatives for other enterobacterial species, which exhibit similar promoter architectures. The GlmY and GlmZ sRNAs of Y.

Dual control by perfectly overlapping sigma 54- and sigma 70- promoters adjusts small RNA GlmY expression to different environmental signals.

In Escherichia coli synthesis of glucosamine-6-phosphate synthase GlmS is feedback-controlled by a regulatory cascade composed of small RNAs GlmY and GlmZ. When GlcN6P becomes limiting, GlmY accumulates and inhibits processing of GlmZ. Full-length GlmZ base-pairs with the glmS transcript and activates synthesis of GlmS, which re-synthesizes GlcN6P.

The small RNA GlmY acts upstream of the sRNA GlmZ in the activation of glmS expression and is subject to regulation by polyadenylation in Escherichia coli.

In Escherichia coli the glmS gene encoding glucosamine 6-phosphate (GlcN-6-P) synthase GlmS is feedback regulated by GlcN-6-P in a pathway that involves the small RNA GlmZ. Expression of glmS is activated by the unprocessed form of GlmZ, which accumulates when the intracellular GlcN-6-P concentration decreases. GlmZ stabilizes a glmS transcript that derives from processing.

Feedback control of glucosamine-6-phosphate synthase GlmS expression depends on the small RNA GlmZ and involves the novel protein YhbJ in Escherichia coli.

Amino sugars are essential precursor molecules for the biosynthesis of bacterial cell walls. Their synthesis pathway is initiated by glucosamine-6-phosphate (GlcN-6-P) synthase (GlmS) which catalyses the rate limiting reaction. We report here that expression of the Escherichia coli glmS gene is negatively feedback regulated by its product GlcN-6-P at the post-transcriptional level.

Genetic dissection of specificity determinants in the interaction of HPr with enzymes II of the bacterial phosphoenolpyruvate:sugar phosphotransferase system in Escherichia coli.

The histidine protein (HPr) is the energy-coupling protein of the phosphoenolpyruvate (PEP)-dependent carbohydrate:phosphotransferase system (PTS), which catalyzes sugar transport in many bacteria. In its functions, HPr interacts with a number of evolutionarily unrelated proteins. Mainly, it delivers phosphoryl groups from enzyme I (EI) to the sugar-specific transporters (EIIs).