TABLE 4.

Main metabolic pathways affected by Hfq

Metabolic pathwayaEnzyme(s) (genes)b
Glycolysis/gluconeogenesis + TCAPhosphoglycerate kinase (pgk); pyruvate kinase II (pykA); malate dehydrogenase (mdh)
Mixed acid fermentationPyruvate kinase II (pykA); alcohol dehydrogenase/acetaldehyde dehydrogenase (adhE); malate deydrogenase (mdh)
Peptidoglycan biosynthesis via UDP-N-acetyl-d-glucosamine pathwayl-Glutamine:d-fructose-6-phophate aminotransferase (glmS); glucosamine-1-phosphate acetyltransferase/N-acetylglucosamine-1-phosphate uridyltransferase (glmU); UDP-N-acetylglucosmanine enolpyruvoyl transferase (murA)
KDO2-lipid A biosynthesisUDP-3-O-[3-hydroxymyristoyl]glucosamine N-acetyltransferase (lpxD); palmitoleoyl acyltransferase (lpxP)
Histidine biosynthesis IATP phosphoribosyltransferase (hisG); imidazole glycerol phosphate synthase (hisH subunit); imidazole glycerol phosphate dehydratase/histidinol-phosphatase (hisB); histidinol-phosphate aminotransferase (hisC); histidinol/histidinal dehydrogenase (hisD)
Threonine biosynthesisAspartate kinase I/homoserine dehydrogenase I (thrA); homoserine kinase (thrB); threonine synthase (thrC)
Glutamate biosynthesisGlutamine synthetase (glnA); glutamate synthase (gltD subunit); glutamate dehydrogenase (gdhA)
Aspartate biosynthesisAspartate transaminase (aspC)
Cysteine biosynthesisCysteine synthase A (cysK)
Alanine biosynthesisCysteine desulfurase (iscS)
Leucine biosynthesisIsopropylmalate isomerase (leuC); 3-isopropylmalate dehydrogenase (leuB)
Aminoacyl-tRNA synthetases(valS, leuS, aspS, thrS)
  • a Only metabolic pathways are listed that contain at least two genes that are significantly differentially regulated by Hfq or are connected to other affected pathways.

  • b Enzymes in which their encoding mRNAs are significantly regulated by Hfq. Genes in boldface have mRNAs that decrease in hfq mutants; enzymes in regular typeface have mRNAs that increase in hfq mutants.