Mitchell complexes

The lac repressor monomer, a chain of 360 amino acids, associates into a functionally active homotetramer. It is the classic member of a large family of bacterial repressors with homologous amino acid sequences. PurR, which functions as the master regulator of purine biosynthesis, is another member of this family. In contrast to the lac repressor, the functional state of PurR is a dimer. The crystal structures of these two members of the Lac I family, in their complexes with DNA fragments, are known. The structure of the tetrameric lac repressor-DNA complex was determined by the group of Mitchell Lewis, University of Pennsylvania, Philadelphia, and the dimeric PurR-DNA complex by the group of Richard Brennan, Oregon Health Sciences University, Portland. 

Mitchell s chemiosmotic hypothesis. The ratio of protons transported per pair of electrons passed through the chain—the so-called HV2 e ratio—has been an object of great interest for many years. Nevertheless, the ratio has remained extremely difficult to determine. The consensus estimate for the electron transport pathway from succinate to Og is 6 H /2 e. The ratio for Complex I by itself remains uncertain, but recent best estimates place it as high as 4 H /2 e. On the basis of this value, the stoichiometry of transport for the pathway from NADH to O2 is 10 H /2 e. Although this is the value assumed in Figure 21.21, it is important to realize that this represents a consensus drawn from many experiments. 

Mitchell, M., P.T.IIrabor and J.P.Crutchfield, Revisiting the edge of chaos evolving cellular automata to perform computations, Complex Systems, Volume 7, 1993, 89-130. 

The absolute configuration of transition metal complexes. R. D. Gillard and P. R. Mitchell, Struct. Bonding (Berlin), 1970,7, 46-86 (165). 

Gillard RD, Mitchell PR (1970) The Absolute Configuration of Transition Metal Complexes. 7 46-86... 

Stockman BJ, Waldon DJ, Gates JA, Schaill TA, Kloosterman DA, Mizsak SA, Jacobsen EJ, Belonga KL, Mitchell MA, Mao B, Petke JD, Goodman L, Powers EA, Ledbetter SR, Kaytes PS, Yogeli G, Marshall VP, Petzold GL, Poorman RA. Solution structure of stromelysin complexed to thiadiazole inhibitors. Prot Sci 1998 7 2281-2286. 

COMPLEX FORMATION IN ELECTRON-ION RECOMBINATION OF MOLECULAR IONS R. Johnsen and J. B. A. Mitchell 49... 

Code CF, Schlegel JF The gastrointestinal housekeeper. Motor correlates of the interdigestive myoelectric complex of the dog. Proceedings from the 4th International Symposium on Gastro-Intestinal Motility. Vancouver, Mitchell Press, 1974, pp 631-634. 

Henbest and Mitchell [78] have shown that water can be used as hydrogen source with chloroiridic acid (6) as the catalyst through oxidation of phosphorous acid (59) to phosphoric acid (60) in aqueous 2-propanol. Under these conditions, no hydrogen transfer occurs from 2-propanol. However, iridium complexes with sulfoxide or phosphine ligands show the usual transfer from 2-pro-panol [79-81]. 

Mitchell, P. (1975) Protonmotive redox mechanism of the cytochrome b-c1 complex in the respiratory chain protonmotive ubiquinone cycle, FEBS Lett., 56, 1-6. 

In reality, it is believed that the oxidation of carbonaceous surfaces occurs through adsorption of oxygen, either immediately releasing a carbon monoxide or carbon dioxide molecule or forming a stable surface oxygen complex that may later desorb as CO or C02. Various multi-step reaction schemes have been formulated to describe this process, but the experimental and theoretical information available to-date has been insufficient to specify any surface oxidation mechanism and associated set of rate parameters with any degree of confidence. As an example, Mitchell [50] has proposed the following surface reaction mechanism ... 

Mitchell, W. Singh, K. 1996. Survival of businesses using collaborative relationships to commercialize complex goods. Strategic Management journal, 17(3) 169-196. 

The proton-motive Q-cycle model, put forward by Mitchell (references 80 and 81) and by Trumpower and co-workers, is invoked in the following manner (1) One electron is transferred from ubiquinol (ubiquinol oxidized to ubisemi-quinone see Figure 7.27) to the Rieske [2Fe-2S] center at the Qo site, the site nearest the intermembrane space or p side (2) this electron can leave the bci complex via an attached cytochrome c or be transferred to cytochrome Ci (3) the reactive ubisemiquinone reduces the low-potential heme bL located closer to the membrane s intermembrane (p) side (4) reduced heme bL quickly transfers an electron to high-potential heme bn near the membrane s matrix side and (5) ubiquinone or ubisemiquinone oxidizes the reduced bn at the Qi site nearest the matrix or n side. Proton translocation results from the deprotonation of ubiquinol at the Qo site and protonation of ubisemiquinone at the Qi site. Ubiquinol generated at the Qi site is reoxidized at the Qo site (see Figure 7.27). Additional protons are transported across the membrane from the matrix (see Figure 7.26 illustrating a similar process for cytochrome b(6)f). The overall reaction can be written... 

Mitchell, K.A., Markham, K.R., and Bayly, M.J., Flavonoid characters contributing to the taxonomic revision of the Hebe parviflora complex. Phytochemistry, 56, 453, 2001. 

The Seven Mysteries of Life by Guy Murchie Butterfly Economics A New General Theory of Social and Economic Behavior by Paul Omerod Paul Ormerod, Swarm Intelligence From Natural to Artificial Systems by Eric Bonabeau, Marco Dorigo Guy Theraulaz, Hidden Order How Adaptation Builds Complexity by John H. Holland Heather Mimnaugh, Turtles, Termites, and Traffic Jams by Mitchel Resnick The Evolution of Cooperation by Robert Axelrod. 

Carter, M. L., Vance, E. R., Mitchell, D. R. G., Hanna, J. V., Zhang, Z. Loi, E. 2002. Fabrication, characterisation, and leach testing of hollandite, (Ba,Cs)(Al,Ti)2Ti6016. Journal of Materials Research, 17, 2578-2589. Chakhmouradian, A. R. Mitciiiill, R. H. 1998. Lueshite, pyrochlore and monazite-(Ce) from apatite-dolomite carbonatite, Lesnaya Varaka complex, Kola Peninsula, Russia. Mineralogical Magazine, 62, 769-782. 

Mitchell, R. H. Chakhmouradian, A. R. 1998a. Th-rich loparite from the Khibina alkaline complex, Kola Peninsula isomorphism and para-genesis. Mineralogical Magazine, 62, 341-353. 

Hamilton SR, Bobrowicz P, Bobrowicz B, Davidson RC, Li H, Mitchell T, Nett JH, Rausch S, Stadheim TA, Wischnewski H, Wildt S, Gerngross TU. Production of complex human glycoproteins in yeast. Science 2003 301 1244-1246. 

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