BEGIN:VCALENDAR VERSION:2.0 PRODID:researchseminars.org CALSCALE:GREGORIAN X-WR-CALNAME:researchseminars.org BEGIN:VEVENT SUMMARY:Hugo Dourado (Heinrich-Heine-Universität Düsseldorf) DTSTART:20220428T153000Z DTEND:20220428T160000Z DTSTAMP:20260421T124126Z UID:MoRN/52 DESCRIPTION:Title: Op timality principles of cellular resource allocation: enzyme/substrate rela tionship and growth laws\nby Hugo Dourado (Heinrich-Heine-Universität Düsseldorf) as part of Seminar on the Mathematics of Reaction Networks\n \n\nAbstract\nMuch recent progress has been made to understand the impact of proteome allocation on bacterial growth\; much less is known about the relationship between the abundances of the enzymes and their substrates\, which jointly determine metabolic fluxes. Here\, we suggest an optimal rel ationship between the concentrations of enzymes and their substrates as a consequence of the optimal biomass allocation: for a cellular reaction ne twork composed of effectively irreversible reactions\, maximal reaction fl ux is achieved when the dry mass allocated to each substrate is equal to t he dry mass of the unsaturated (or “free”) enzymes waiting to consume it. Calculations based on this optimality principle successfully predict t he quantitative relationship between the observed enzyme and metabolite ab undances in E. coli\, parameterized only by dissociation constants ($K_m$) . This optimal relationship is also shown to explain the emergence of line ar “growth laws” of proteome allocation under carbon limitation\; thes e can be seen as approximations to the optimal enzyme/substrate relationsh ip\, including the existence of aparent protein “offsets” at zero grow th. The apparent offsets relate directly to the levels of substrate satura tion of catalytic proteins\, explaining also how the “under-utilization ” of enzymes results from a trade-off between biomass allocation to enzy mes and to metabolites.\n LOCATION:https://researchseminars.org/talk/MoRN/52/ END:VEVENT END:VCALENDAR