Editing Pyruvate kinase (section)

== Isozymes in bacteria ==
Many Enterobacteriaceae, including ''[[Escherichia coli|E. coli]]'', have two isoforms of pyruvate kinase, PykA and PykF, which are 37% identical in ''E. coli'' (Uniprot: [https://www.uniprot.org/uniprot/P21599 PykA], [https://www.uniprot.org/uniprot/P0AD61 PykF]). They catalyze the same reaction as in eukaryotes, namely the generation of ATP from ADP and PEP, the last step in [[glycolysis]], a step that is irreversible under physiological conditions. PykF is allosterically regulated by FBP which reflects the central position of PykF in cellular metabolism.<ref name="Valentini 18145–18152">{{cite journal | vauthors = Valentini G, Chiarelli L, Fortin R, Speranza ML, Galizzi A, Mattevi A | title = The allosteric regulation of pyruvate kinase | journal = The Journal of Biological Chemistry | volume = 275 | issue = 24 | pages = 18145–52 | date = June 2000 | pmid = 10751408 | doi = 10.1074/jbc.M001870200 | doi-access = free }}</ref> PykF transcription in ''E. coli'' is regulated by the global transcriptional regulator, Cra (FruR).<ref>{{cite journal | vauthors = Ramseier TM, Nègre D, Cortay JC, Scarabel M, Cozzone AJ, Saier MH | title = In vitro binding of the pleiotropic transcriptional regulatory protein, FruR, to the fru, pps, ace, pts and icd operons of Escherichia coli and Salmonella typhimurium | journal = Journal of Molecular Biology | volume = 234 | issue = 1 | pages = 28–44 | date = November 1993 | pmid = 8230205 | doi = 10.1006/jmbi.1993.1561 }}</ref><ref>{{cite journal | vauthors = Ramseier TM, Bledig S, Michotey V, Feghali R, Saier MH | title = The global regulatory protein FruR modulates the direction of carbon flow in Escherichia coli | journal = Molecular Microbiology | volume = 16 | issue = 6 | pages = 1157–69 | date = June 1995 | pmid = 8577250 | doi = 10.1111/j.1365-2958.1995.tb02339.x | s2cid = 45447144 }}</ref><ref>{{cite journal | vauthors = Saier MH, Ramseier TM | title = The catabolite repressor/activator (Cra) protein of enteric bacteria | journal = Journal of Bacteriology | volume = 178 | issue = 12 | pages = 3411–7 | date = June 1996 | pmid = 8655535 | pmc = 178107 | doi = 10.1128/jb.178.12.3411-3417.1996 }}</ref> PfkB was shown to be inhibited by MgATP at low concentrations of Fru-6P, and this regulation is important for [[gluconeogenesis]].<ref>{{cite journal | vauthors = Sabnis NA, Yang H, Romeo T | title = Pleiotropic regulation of central carbohydrate metabolism in Escherichia coli via the gene csrA | journal = The Journal of Biological Chemistry | volume = 270 | issue = 49 | pages = 29096–104 | date = December 1995 | pmid = 7493933 | doi = 10.1074/jbc.270.49.29096 | doi-access = free }}</ref>