THE EQUILIBRIUM CONSTANT FOR THE GLYCINE SYNTHASE REACTION (ONE-CARBON, METABOLISM, FOLATE)

The equilibrium constant (K(,c)) under physiological conditions (38(DEGREES)C, 0.25 M ionic strength (I), pH 7.0) for the glycine synthase (GS) reaction (E C 2.1.2.1.0) (Equation 1) has been determined. (UNFORMATTED TABLE FOLLOWS)^ 5,10-CH(,2)-H(,4)Folate NADH NH (,4)+ CO(,2) ^ K(,c) = Eq. 1^ H(,4)Folate NAD('+) GLY ^(TABLE ENDS)^ The enzymatic instability of the GS enzyme complex itself has made it necessary to determine the overall K(,c) from the product of constants for the partial reactions of GS determined separately under the same conditions. The partial reactions are the H(,4)Folate-formaldehyde (CH(,2)(OH)(,2)) condensation reaction (Reaction 1) the K(,c) for which has been reported by this laboratory (3.0 x 10('4)), the lipoate (LipS(,2)) dehydrogenase reaction (LipDH) (Reaction 2) and the Gly-Lip^ decarboxylase reaction (Reaction 3) forming reduced lipoate (Lip(SH)(,2)), NH(,4)('+), CO(,2) and CH(,2)(OH)(,2.) (UNFORMATTED TABLE FOLLOWS)(,)^ H(,4)Fote + CH(,2)(OH)(,2) 5,10-CH(,2)-H(,4)Folate (1)^ Lip(SH)(,2) + NAD('+) LipS(,2) + NADH + H('+) (2)^ H('+) + Gly + LipS(,2) Lip(SH)(,2) + NH(,4)('+) CO(,2) + CH(,2)(OH)(,2) (3)^(TABLE ENDS)^ In this work the K(,c) for Reactions 2 and 3 are reported.^ The K(,c)' for the LipDH reaction described by other authors was reported with unexplainable conclusions regarding the pH depend- ence for the reaction. These conclusions would imply otherwise unexpected acid dissociation constants for reduced and oxidized lipoate. The pK(,a)',s for these compounds have been determined to resolve discrepancy. The conclusions are as follows: (1) The K(,c) for the LipDH reaction is 2.08 x 10('-8); (2) The pK(,a)',s for Lip(SH)(,2) are 4.77(-COOH), 9.91(-SH), 11.59(-SH); for LipS(,2) the carboxyl pK(,a)' is 4.77; (3) Contrary to previous literature, the log K(,c)' for the LipDH reaction is a linear function of the pH, a conclusion supported by the values for the dissociation constants.^ The K(,c) for Reaction 3 is the product of constants for Reactions 4-7. (UNFORMATTED TABLE FOLLOWS)^ LipSHSCH(,2)OH + H(,2)O Lip(SH)(,2) + CH(,2)(OH)(,2) (4)^ H(,2)O + LipSHSCH(,2)NH(,3)('+) LipSHSCH(,2)OH + NH(,4)('+) (5)^ LipSHSCH(,2)NH(,2) + H('+) LipSHSCH(,2)NH(,3)('+) (6)^ Gly + LipS(,2) LipSHSCH(,2)NH(,2) + CO(,2) (7)^(TABLE ENDS)^ Reactions 4-6 are non-enzymatic reactions whose constants were determined spectrophotometrically. Reaction 7 was catalyzed by the partially purified P-protein of GS with equilibrium approached from both directions. The value for K(,c) for this reaction is 8.15 x 10('-3). The combined K(,c) for Reactions 4-7 or Reaction 3 is 2.4 M.^ The overall K(,c) for the GS reaction determined by combination of values for Reactions 1-3 is 1.56 x 10('-3). ^

An Equilibrium Model of Lawmaking

This paper embeds a model of lawmaking in an equilibrium framework in which the demand for trials is rationed by court delay. The lawmaking process depends on a combination of selective litigation, judicial bias, and precedent. The steady state equilibrium of the model determines both the length of delay and the distribution of legal rules. Comparative statics show that an increase in the supply of trials reduces delay but may or may not increase the proportion of efficient rules. An increase in the fraction of judges biased in favor of the efficient rule, however, will likely improve efficiency on both counts.

Nitric Oxide Equilibrium

The explicit formulas for following the passage to chemical equilibrium are derived.

Stationary Markovian Equilibrium in Overlapping Generation Models with Stochastic Nonclassical Production

This paper provides new sufficient conditions for the existence, computation via successive approximations, and stability of Markovian equilibrium decision processes for a large class of OLG models with stochastic nonclassical production. Our notion of stability is existence of stationary Markovian equilibrium. With a nonclassical production, our economies encompass a large class of OLG models with public policy, valued fiat money, production externalities, and Markov shocks to production. Our approach combines aspects of both topological and order theoretic fixed point theory, and provides the basis of globally stable numerical iteration procedures for computing extremal Markovian equilibrium objects. In addition to new theoretical results on existence and computation, we provide some monotone comparative statics results on the space of economies.

On the Existence and Characterization of Markovian Equilibrium in Models with Simple Non-Paternalistic Altruism

This paper provides sufficient conditions for existence of Markovian equilibrium in models with non-paternalistic altruism extending to one generation ahead. When utility is non-separable, we show that each equilibrium savings policy correspondence is increasing everywhere and single-valued, except perhaps on a countable number of points. It is also upper hemi-continuous where it is single valued. When utility is separable, we show that the equilibrium is unique, increasing, and continuous, and we provide an algorithm converging uniformly to the equilibrium.

Existence and Uniqueness of Equilibrium in Nonoptimal Unbounded Infinite Horizon Economies

In applied work in macroeconomics and finance, nonoptimal infinite horizon economies are often studied in the the state space is unbounded. Important examples of such economies are single vector growth models with production externalities, valued fiat money, monopolistic competition, and/or distortionary government taxation. Although sufficient conditions for existence and uniqueness of Markovian equilibrium are well known for the compact state space case, no similar sufficient conditions exist for unbounded growth. This paper provides such a set of sufficient conditions, and also present a computational algorithm that will prove asymptotically consistent when computing Markovian equilibrium.

Advanced Physical Chemistry Problems (VIII), Chemical Equilibrium

This is a set of P. Chem. problems posed at a slightly higher level than the normal textbook level, for students who are continuing in the study of this subject.

Integration versus Outsourcing in Stable Industry Equilibrium with Communication Networks

For the selection of a firm's structure between vertical integration and arm's-length outsourcing, the importance of the thickness of the market had been emphasized in the previous literature. Here we take account of communication networks such as telephone, telex, fax, and the Internet. By doing so, we could illustrate the relationship between communication networks and the make-or-buy decision. With communication network technology differing in each type of firm, both vertically integrated firms and arm's-length outsourcing firms coexist, which was never indicated in the previous literature. However, when common network technology is introduced, such coexistence generically does not occur.

Chapter 2 Equilibrium locations of upstream and downstream firms

This paper explores the interaction between upstream firms and downstream firms in a two-region general equilibrium model. In many countries, lower tariff rates are set for intermediate manufactured goods and higher tariff rates are set for final manufactured goods. The derived results imply that such settings of tariff rates tend to preserve a symmetric spread of upstream and downstream firms, and continuing tariff reduction may cause core-periphery structures. In the case in which the circular causality between upstream and downstream firms is focused as agglomeration forces, the present model is fully solved. Thus, we find that (1) the present model displays, at most, three interior steady states, (2) when the asymmetric steady-states exist, they are unstable and (3) location displays hysteresis when the transport costs of intermediate manufactured goods are sufficiently high.

Domestic, vertical, and horizontal multinationals : a general equilibrium approach using the "knowledge capital model"

One of the key factors behind the growth in global trade in recent decades is an increase in intermediate input as a result of the development of vertical production networks (Feensta, 1998). It is widely recognized that the formation of production networks is due to the expansion of multinational enterprises' (MNEs) activities. MNEs have been differentiated into two types according to their production structure: horizontal and vertical foreign direct investment (FDI). In this paper, we extend the model presented by Zhang and Markusen (1999) to include horizontal and vertical FDI in a model with traded intermediates, using numerical general equilibrium analysis. The simulation results show that horizontal MNEs are more likely to exist when countries are similar in size and in relative factor endowments. Vertical MNEs are more likely to exist when countries differ in relative factor endowments, and trade costs are positive. From the results of the simulation, lower trade costs of final goods and differences in factor intensity are conditions for attracting vertical MNEs.