{"id":15733,"date":"2022-06-24T13:34:42","date_gmt":"2022-06-24T06:34:42","guid":{"rendered":"https:\/\/bgrssb.icgbio.ru\/2022\/?p=15733"},"modified":"2022-09-20T10:32:31","modified_gmt":"2022-09-20T03:32:31","slug":"on-the-question-of-activity-of-oxidative-branch-of-pentose-phosphate-shunt-in-pgl-mutant-of-e-coli","status":"publish","type":"post","link":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/2022\/06\/24\/on-the-question-of-activity-of-oxidative-branch-of-pentose-phosphate-shunt-in-pgl-mutant-of-e-coli\/","title":{"rendered":"On the question of activity of oxidative branch of Pentose Phosphate shunt in pgl mutant of E. coli"},"content":{"rendered":"<p><em>by Kovaleva E. | Shepelin D. | Baboshin M. | Golubeva L. | Mashko S. | Ajinomoto-Genetika Research<\/em><br \/>\n<em>Institute, 117545, Moscow, Russian Federation | Recent affiliation: Novo Nordisk Foundation Center for<\/em><br \/>\n<em>Biosustainability, Technical University of Denmark, DK-2800 Lyngby, Denmark\u00a0<\/em><\/p>\n<p><strong>Motivation and aim<\/strong>: 13C metabolic flux analysis (13C-MFA) is complex method for<br \/>\nquantitative estimation of actual carbon metabolic fluxes distribution in vivo.<br \/>\nThere are still unsolved questions even about E. coli metabolism. By flux balance analysis<br \/>\n(FBA) of E. coli BL21 with 6-phosphogluconolactonase (pgl) deficient genotype,<br \/>\ninvestigators assume inactivation of oxidative branch of pentose phosphate pathway (oxPPP)<br \/>\nin this strain. But 13C-MFA of BL21 and MG1655 \u0394pgl demonstrated only insignificant<br \/>\ndecrease of oxPPP flux. We hypothesized that flux through oxPPP is actually reduced, but<br \/>\nnot to zero, in pgl mutant.<br \/>\n<strong>Methods and Algorithms<\/strong>:<br \/>\n13C-MFA of E. coli strains grown on minimal medium with<br \/>\n20%\/80% mixture of [1-13C]- and [U-13C]-glucose. Flux calculation and statistical analysis of<br \/>\ncalculated carbon flux distribution was provided by OpenFLUX2 software based on<br \/>\nproteinogenic amino acids and monosaccharides labeling data.<br \/>\n<strong>Results<\/strong>: Flux solution with the best accordance with experimental data for \u0394pgl mutant<br \/>\ncorresponds to 18% oxPPP carbon flux of input glucose in contrast with 25% in parent<br \/>\nstrain. Flux calculation under assumption that pgl inactivation blocks oxPPP resulted in<br \/>\nstatistically unacceptable solutions. We determined that flux through PGL reaction<br \/>\nresponded to \u03c72-criterion on minimal 10% level.<br \/>\nIt is known that simultaneous oxPPP and pntAB genes inactivation resulted in drastic<br \/>\ndecrease of growth rate caused by NADPH deficiency. Previously it was proposed that the<br \/>\nspecific bypass through gluconate can functioning in \u0394pgl mutant. Simultaneous<br \/>\ninactivation of major gluconate importers reduces growth of \u0394pgl and \u0394pgl\u0394pntAB mutants<br \/>\non glucose. Gluconate bypass can participate in oxPPP flux keeping in pgl deficient strain.<br \/>\n<strong>Conclusions<\/strong>: Proposal of inactive oxPPP in pgl deficient E. coli mutant contradicts to 13CMFA of carbon flux distribution in MG1655\u0394pgl strain and to growth characteristics of double mutants, with inactivated pntAB and oxPPP genes. According to 13C-MFA the flux<br \/>\nthrough the oxPPP decreases by no more than 2.5-times in the MG1655\u0394pgl strain.<\/p>\n<a href=\"https:\/\/bgrssb.icgbio.ru\/2022\/wp-content\/uploads\/sites\/3\/2022\/06\/BGRS-SB-2022_Kovaleva.pdf\" class=\"pdfemb-viewer\" style=\"\" data-width=\"max\" data-height=\"max\"  data-toolbar=\"bottom\" data-toolbar-fixed=\"off\">BGRS-SB-2022_Kovaleva<br\/><\/a>\n","protected":false},"excerpt":{"rendered":"<p>by Kovaleva E. | Shepelin D. | Baboshin M. | Golubeva L. | Mashko S. | Ajinomoto-Genetika Research Institute, 117545, Moscow, Russian Federation | Recent affiliation: Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, DK-2800 Lyngby, Denmark\u00a0 Motivation and aim: 13C metabolic flux analysis (13C-MFA) is complex method for quantitative estimation of actual [&hellip;]<\/p>\n","protected":false},"author":3967,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":[],"categories":[9],"tags":[198,199,200],"_links":{"self":[{"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/posts\/15733"}],"collection":[{"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/users\/3967"}],"replies":[{"embeddable":true,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/comments?post=15733"}],"version-history":[{"count":1,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/posts\/15733\/revisions"}],"predecessor-version":[{"id":15735,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/posts\/15733\/revisions\/15735"}],"wp:attachment":[{"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/media?parent=15733"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/categories?post=15733"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/bgrssb.icgbio.ru\/2022\/ru\/wp-json\/wp\/v2\/tags?post=15733"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}