A mathematical model for examining growth and sporulation processes of <i>Bacillus subtilis</i>

Jeong, Jin-Wook; Snay, J.; Ataai, Mohammad M.

doi:10.1002/bit.260350208

Cited by 53 publications

(20 citation statements)

References 90 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The concentrations of pyruvate, 2-oxoglutarate, and glutamate in the wild-type strain were similar to the corresponding values obtained in B. subtilis (15,21,47), whereas the oxaloacetate level was more than 600-fold higher. Both the L-lysine and glutamate levels in the mutant strain were substantially higher (29-and 6-fold, a Cells were grown in MVcMY medium in 1-liter baffled shake flasks at 50°C until stationary phase, and crude extracts were prepared and measured for metabolite concentrations as described in the text.…”

Section: Resultssupporting

confidence: 84%

Role of the Bacillus methanolicus Citrate Synthase II Gene, citY , in Regulating the Secretion of Glutamate in l -Lysine-Secreting Mutants

Brautaset

Williams

Dillingham

et al. 2003

Appl Environ Microbiol

View full text Add to dashboard Cite

The unusual metabolic properties of aerobic, restrictive, thermotolerant methylotrophic bacteria make them useful for the production of recombinant proteins, vitamins, amino acids, coenzymes, and cytochromes (12). Bacillus methanolicus MGA3 (ATCC 53907) is a gram-positive bacterium with a growth optimum of 50°C to 53°C. Cell extracts of this bacterium grown on methanol contain an NAD-dependent methanol dehydrogenase (3, 13), have 3-hexulose-6-phosphate synthase, fructose bisphosphate aldolase, and transaldolase activity indicative of the fructose bisphosphate aldolase/ transaldolase variant of the ribulose monophosphate pathway, RuMP (4, 14, 44). The precursors (acetyl-coenzyme A, pyruvate, oxaloacetate, and 2-oxoglutarate) for lipids, amino acids, nucleic acids, and assimilation of ammonia are all synthesized from the products of the RuMP pathway (2). The dissimilation of carbon from formaldehyde to CO 2 in B. methanolicus, which may function to detoxify accumulating formaldehyde, has recently been confirmed by 13 C nuclear magnetic resonance and isotope ratio mass spectrometry (39). The theoretical yield of secreted amino acids varies depending on the percentage of formaldehyde carbon dissimilated to CO 2 (39), and therefore control of the feeding of methanol to fed-batch cultures is critical (29).Homoserine dehydrogenase mutants (HSD Ϫ ) of B. methanolicus, which are threonine plus methionine auxotrophs, have been shown to secrete substantial quantities of L-lysine when grown at 50°C in fed-batch cultures on methanol as a sole carbon source and supplied with a source of ammonia (18,29,44). B. methanolicus HSD Ϫ strain 13A52-8A66 can secrete over 60 g of L-lysine plus glutamate (glutamate) per liter, with a mass yield of 0.50 to 0.63 g/g. However, no mutants that secrete only L-lysine have been found with this approach; all simultaneously secrete significant quantities of glutamate and smaller amounts of alanine.Limited knowledge exists for most aerobic methylotrophs of the genetic basis of the regulation of pyruvate metabolism, the activity of tricarboxylic acid (TCA) cycle enzymes during rapid growth on methanol (7,13,54), and particularly regulation of the flow of carbon to amino acid biosynthesis (20,(31)(32)(33)46). To accomplish high-level L-lysine production, the percentage of carbon dissimilated to CO 2 must be minimized to generate an abundant supply of aspartate (37). In Bacillus subtilis, aspartate is synthesized from oxaloacetate by aspartate aminotransferase (glutamate:oxaloacetate transaminase) encoded by aspB, which appears to be constitutively expressed (5).The simultaneous production of glutamate and L-lysine in B. methanolicus mutants indicates a substantial flow of carbon both to aspartate and into the first three reactions of the TCA cycle catalyzed by citrate synthase (CS), aconitase, and isocitrate dehydrogenase (Fig. 1). Since many methylotrophs generate reducing power by the oxidation of formaldehyde to

show abstract

Section: Resultssupporting

confidence: 84%

Role of the Bacillus methanolicus Citrate Synthase II Gene, citY , in Regulating the Secretion of Glutamate in l -Lysine-Secreting Mutants

Brautaset

Williams

Dillingham

et al. 2003

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…No selection can be inclusive, so what is the role of compounds that are left out? Jeong et al [450] made a heroic attempt to model the compound-based physiology of Bacillus and introduced more than 200 parameters. However, many compounds have yet to be identified and the quantities and dynamics of most compounds are largely unknown.…”

Section: Energeticsmentioning

confidence: 99%

Dynamic Energy and Mass Budgets in Biological Systems

Kooijman

2000

793

1,202

View full text Add to dashboard Cite

second editionDynamic Energy Budget theory unifies the commonalities between organisms as prescribed by the implications of energetics, which link different levels of biological organization (cells, organisms and populations). The theory presents simple mechanistic rules that describe the uptake and use of energy and nutrients and the consequences for physiological organization throughout an organism's life cycle, including the relationships between energetics and aging and the effects of toxicants. In this new edition, the theory is broadened to encompass the fluxes of both energy and mass. All living organisms are now covered in a single quantitative framework, the predictions of which are tested against a wide variety of experimental results at the various levels of biological organization. The theory explains many general observations, such as the body size scaling relationships of certain physiological traits, and provides a theoretical basis for the widely used method of indirect calorimetry. In each case, the theory is developed in elementary mathematical terms, but a more detailed discussion of the methodological aspects of mathematical modelling is also included, making the book suitable for biologists and mathematicians with a broad interest in both fundamental and applied quantitative problems in biology.Bas Kooijman is Professor of Applied Theoretical Biology at the Vrije Universiteit in Amsterdam and is also head of the University's Department of Theoretical Biology. His research focuses on mathematical biology, in particular ecotoxicology which provided the framework for the original version of his Dynamic Energy Budget theory published in 1993 (Dynamic Energy Budgets in Biological Systems -Theory and Applications in Ecotoxicology). From the first edition:"This book is an excellent scientific product that informs and forces contemplation of issues relating to population and community ecology. The author has made a complex subject coherent." Thomas G. Hallam, Bulletin of Mathematical Biology "... a very useful and general tool to select more ecologically sound process equations and parameters in ecological models." Sven Erik Jørgensen, Ecological Modelling "The author has made a significant contribution to the problem of modelling the dynamics of biological populations at the level of the individual by synthesizing this very complicated subject into a relatively short list of general assumptions and putting the energetics of sub-models for vital rates on a solid basis." Jim Cushing, Mathematical Biosciences "The family of idealized models offered in this book is capable of playing a role analogous to that of Lotka-Volterra models in population dynamics ... I am confident that any model(s) capable of occupying this niche will be strongly influenced by the ideas in this book." Roger Nisbet, Ecology 9 LIVING TOGETHER Interaction between organisms: The spectrum from competition to preypredator systems. Evaluation of the consequences of the DEB model for population dynamics, food chains, and communities....

show abstract

“…Another E. coli model published by Domach et al in 1984 included the transport of glucose and ammonium ions, and the synthesis of polymer precursors and polymers (Domach et al, 1984). A model of Bacillus subtilis published by Jeong et al in 1990 consisted of 35 cell-constituent components and 39 continuous ordinary-differential equations; this enabled changes from the exponential growth phase to the stationary phase in batch culture to be calculated (Jeong et al, 1990).…”

Section: Microorganism Metabolic Modelsmentioning

confidence: 99%

Metabolome analysis and metabolic simulation

et al. 2005

View full text Add to dashboard Cite

For many decades microorganisms have been used for industrial purposes; traditional fermentations such as brewing and production of food additives, aroma molecules, organic acids and pharmaceutical-like antibiotics or recombinant proteins are instances of the industrial microorganism utilization. Therefore, microorganism modeling and simulation have been required for engineering purposes, because of demands for design, optimization and quality control of large-scale fermentation plants.Modeling has recently become more highly developed, aided by the deciphering of microorganism genomes, the completion of metabolic databases, the development of analytical methodologies and improvements in the performance of computers. This paper reviews past and recent metabolic simulation of microorganisms, and also discusses the metabolome analytical techniques and the construction of large-scale microorganism models which are now being developed in our group.

show abstract

A mathematical model for examining growth and sporulation processes of Bacillus subtilis

Cited by 53 publications

References 90 publications

Role of the Bacillus methanolicus Citrate Synthase II Gene, citY , in Regulating the Secretion of Glutamate in l -Lysine-Secreting Mutants

Role of the Bacillus methanolicus Citrate Synthase II Gene, citY , in Regulating the Secretion of Glutamate in l -Lysine-Secreting Mutants

Dynamic Energy and Mass Budgets in Biological Systems

Metabolome analysis and metabolic simulation

Contact Info

Product

Resources

About