Enzyme homogeneous

Purity homogenous clarified crude extract crude enzyme homogeneous... 

Burk plot of the activity of the enzyme homogenates of the Experimental ganglia and the Control ganglia. The two enzymatic preparations had the same Vmax but they had different Kms. The Km for the Experimental ganglia was 1.33 x 10 4 moles whilst that for the Control was 5.88 x 10 5 moles. This suggests that the difference between the enzyme in the two preparations is that probably both have the same number of active sites (same Vmax) but that there is a difference in the affinity between the active site and the substrate. 

A great variety of homogeneous catalysts are known metal complexes and ions, Bronsted and Lewis acid, enzymes. Homogeneous transition metals are used in several industrial processes, a few of them are given below... 

Homogeneous Transition Metal Catalysts. - There have been comparatively few examples of non-enzymic homogeneous catalysts... 

Reverse mutation S. typhimurlum TA98 and TA100 2.5-50 pg/plate Negative with HepG2-derived enzyme homogenate (S9 mix) Ehrlich et al. (2002)... 

Having defined critical conditions for the examination of outer ring deiodination, similar techniques were applied to the Type III or inner ring deiodinase activity (17-19). The results were anticipated by the initial studies of the enzyme homogenates. The Type III enzyme prefers T3 as a substrate, follows sequential, rather than ping-pong, kinetics and is insensitive to PTU at 10 M (Table 1). Despite the fact that T3 is the preferred substrate for the Type III activity, it is this enzyme which produces rT3 from T4 in the central nervous system. 

Concentration polarization phenomena can be used to form a gel-layer of enzyme proteins on a membrane, in either dynamic or static conditions. It is possible to establish more than one enzyme layer, without a coupling agent to carry out the immobilization. Due to high protein concentration on the membrane surface, enzyme stability can be improved compared with systems using enzymes homogeneously distributed in the reacting solution. 

Sever inorganic catalysts, but also organic catalysts and particularly enzymes, may be used either in a dissolved form, or adsorbed on a solid carrier (in the case of enzymes, the current term is "immobilized enzymes ). Homogeneous catalysis has the potential advantage of more uniform reactant concentration ratios and temperatures, which may be important for the selectivity of the process. This is the case when the catalyst is selected primarily to promote a desired reaction relative to a competitive reaction. When a solid product is formed in a homogeneous catalytic reaction, the control of the nucleation may offer difficulties, see section 6.3.4.3. 

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