Microbe kinetics

Hajjaj, H. et al.. Kinetic analysis of red pigment and citrinin production by Monascus ruber as a function of organic acid accumulation, Enz. Microb. Technol, 27, 619, 2000. 

When microorganisms use an organic compound as a sole carbon source, their specific growth rate is a function of chemical concentration and can be described by the Monod kinetic equation. This equation includes a number of empirical constants that depend on the characteristics of the microbes, pH, temperature, and nutrients.54 Depending on the relationship between substrate concentration and rate of bacterial growth, the Monod equation can be reduced to forms in which the rate of degradation is zero order with substrate concentration and first order with cell concentration, or second order with concentration and cell concentration.144... 

K. Heincke, B. Demuth, H. J. Joerdening, and K. Buchholz, Kinetics of the dextransucrase acceptor reaction with maltose Experimental results and modeling, Enzyme Microb. Technol., 24 (1999) 523-534. 

It is in principle possible for a free enzyme to promote reaction in a geochemical system, but enzyme kinetics are invoked in geochemical modeling most commonly to describe the effect of microbial metabolism. Microbes are sometimes described from a geochemical perspective as self-replicating enzymes. This is of course a considerable simplification of reality, as we will discuss in the following chapter (Chapter 18), since even the simplest metabolic pathway involves a series of enzymes. 

If we choose as representative conditions 1 L molal acetate, 10 p, molal sulfate, and a thermodynamic factor Fj of 0.4, and use the kinetic parameters already cited, D is about 10-9 s 1, a value we carry for both functional groups of microbes. 

J. L. Galazzo and J. E. Bailey, Fermentation pathway kinetics and metabolic flux control in suspended and immobilized Saccharomyces cerevisiae. Enzyme Microb. Technol. 12(3), 162 172 (1990). 

The bio availability of organic compounds in soils/sediments to microbes, plants, and animals is important from the perspective of remediation and risk assessment. Cleanup technology (ex situ or in situ) of contaminated soils and bottom sediments requires mass transport of contaminants through the solid materials, which in turn depends on sorption/desorption kinetics. 

The oxygen demand of the heterotrophic microbes can be measured as the loss of COD. In the absence of oxygen limitation this was also described by equations (6, 7 8) developed from Monod kinetics (15). 

Microbial reduction of nitrate to N2, known as denitrification, is similar. It is kinetically inhibited in the absence of bacteria and is known to induce a kinetic isotope effect (Blackmer and Bremner 1977 Kohl and Shearer 1978 Mariotti et al. 1981 Bryan et al. 1983 Htibner 1986 Mariotti et al. 1988). W N shifts ranging from 6.5%o to 20%o have been observed experimentally. As with sulfate, microbial fractionations appear to depend on the metabolic states of the microbes. 

Figure 4.15 indicates the range of rates of O2 consumption in different soils. Oxygen is consumed in oxidation of inorganic reductants, such as Fe(II), as well as in oxidation of organic matter by microbes. Bouldin (1968) and Howeler and Bouldin (1971) compared measured rates of O2 movement into anaerobic soil cores with the predictions of various models, and obtained the best fits with a model allowing for both microbial respiration and abiotic oxidation of mobile and immobile reductants abiotic oxidation accounted for about half the O2 consumed. The kinetics of the abiotic reactions are complicated. They often depend on the adsorption of the reductant on solid surfaces as, for example, in... 

The E. coli microbe grows contentedly on glucose according to Monod kinetics as follows ... 

The reviewer of the paper. Dr. Ferment, counters that Microbe is quite wrong, that the data in fact represents substrate limiting Monod kinetics with... 

Kasche, V. (1986) Mechanism and yields in enzyme catalysed equilibrium and kinetically controlled synthesis of -lactam antibiotics, peptides and other condensation products. Enzyme Microb. Technol., 8, 4-16. 

Assuming that the local rate of enzyme reaction follows Michaelis-Menten kinetics, or that the microbe film follows Monod kinetics regardless of immobilisation, then equation 5.86 becomes ... 

The kinetics of the microbiological kill reaction is more favorable for bromine. Thus bromine tends to kill microbes more quickly, and for any disinfection time period it will achieve a higher magnitude of kill. This can be important for cooling systems with short disinfection contact times, e.g., once-through systems. 

A. J. Brazier, M. D. Lilly, and A. B. Herbert, Toluene cis-glycol synthesis by Pseudomonas putida kinetic data for reador evaluation, Enzyme Microb. Technol. 1990, 12, 90-94. 

S. Colombie, P. Monsan, and B. Lindet, Lysozyme inactivation by inert gas bubbling kinetics in a bubble column reactor, Enz. Microb. Technol. 1999, 24, 412-418. 

Caussette, M. Gaunnand, A. Planche, H. Colombie, S. Monsan, P. Lindet, B. Lysozyme Inactivation by Inert Gas Bubbling Kinetics in a Bubble Column Reactor. Enzyme Microb. Technol. 1999, 24, 412 -18. 

Wu Y, Taylor KE, Biswas N etal (1998) A model for the protective effect of additives on the activity of horseradish peroxidase in the removal of phenol - a kinetic investigation. Enzyme Microb Technol 22 315-322... 

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