Yeasts structure

In the two complexes studied by x-ray crystallography, the interactions between TBP and the DNA, as well as the deformation of the B-DNA structure, are very similar, and we will illustrate some of these details for the yeast structure. Minor details of the two complexes vary due to differences in some of the side chains and nucleotides that are present in the interaction areas. 

Mechanistically both archaeal MIPS and yeast MIPS(s) are almost similar. Recent detailed mutational study on archaeal MIPS revealed the involvement of same amino acid residues those implicated in the yeast structure and belong... 

The structured model is consistent with features of lytic enzyme action and yeast structure reported in the literature. The sequential removal of the two wall layers, followed by protoplast rupture, accurately describes the early lag in protein and carbohydrate release. The presence of residual solids at long reaction times was accounted for stabilization of protoplasts by substances released from lysed cells. The structured model can be used to estimate the effects of several process alternatives, as shown in a simulation of a process for recovery of site-linked enzymes from yeast. 

The isoenzymes of phosphoglycerate kinase (PGK, EC 2.7.2.3) from barley leaves have been purified in this laboratory and used to raise antisera (1). These antisera were used to isolate the wheat cDNAs, specific for each isoenzyme, which have since been sequenced (2 ). The derived amino acid sequences have been used to build models for the structures of both isoenzymes on an Evans and Sutherland graphics station. The co-ordinates obtained from the x-ray crystallographic studies of the yeast structure, which have been deposited in the Brookhaven protein data bank, have been used as a template (3). 

FIGURE 2 The models for the chloroplast and cytoplasmic isoenzymes superimposed on the yeast structure. 

Page 1176 (Figure 28 11) is adapted from crystallographic coordinates deposited with the Protein Data Bank PDB ID 6TNA Sussman J L Holbrook S R Warrant R W Church G M Kim S H Crystal Structure of Yeast Phenylalanine tRNA I Crystallographic Refinement / Mol Biol 1978 126 607 (1978)... 

Campbell, J.W., Watson, H.C., Hodgson, G.I. Structure of yeast phosphoglycerate mutase. Nature 250 301-303, 1974. 

Lebioda, L., Stec, B., Brewer, J.M. The structure of yeast enolase at 2.5 A resolution. An 8-fold p + a barrel with a novel ppoa(pa)6 topology. /. Biol. Chem. 

Steitz, T.A., et al. High resolution x-ray structure of yeast hexokinase, an allosteric protein exhibiting a non-symmetric arrangement of subunits. 

Xia, Z.-X., et al. Three-dimensional structure of flavocy-tochrome bz from baker s yeast at 3.0 A resolution. Proe. Natl. Aead. Sei. USA 84 2629-2633, 1987. 

Figure 9.3 Comparison of the consensus nucleotide sequence of the TATA box (a) and the sequences of the DNA fragments used in the crystal structure determinations of the TATA box-binding proteins from yeast (b) and the plant Arabidopsis thaliana (c).

Figure 9.12 Schematic diagram of the structure of the heterodimeric yeast transcription factor Mat a2-Mat al bound to DNA. Both Mat o2 and Mat al are homeodomains containing the helix-turn-helix motif. The first helix in this motif is colored blue and the second, the recognition helix, is red. (a) The assumed structure of the Mat al homeodomain in the absence of DNA, based on Its sequence similarity to other homeodomains of known structure, (b) The structure of the Mat o2 homeodomain. The C-terminal tail (dotted) is flexible in the monomer and has no defined structure, (c) The structure of the Mat a 1-Mat a2-DNA complex. The C-terminal domain of Mat a2 (yellow) folds into an a helix (4) in the complex and interacts with the first two helices of Mat a2, to form a heterodimer that binds to DNA. (Adapted from B.J. Andrews and M.S. Donoviel, Science 270 251-253, 1995.)...

Parraga, G., et al. Zinc-dependent structure of a single-finger domain of yeast ADRl. Science 241 1489-1492, 1988. 

FIGURE 10.18 A model for the structure of the a-factor transport protein in the yeast plasma membrane. Gene duplication has yielded a protein with two identical halves, each half containing six transmembrane helical segments and an ATP-binding site. Like the yeast a-factor transporter, the multidrug transporter is postulated to have 12 transmembrane helices and 2 ATP-binding sites. 

FIGURE 12.34 A general diagram for the structure of tRNA. The positions of invariant bases as well as bases that seldom vary are shown in color. The numbering system is based on yeast tRNA R = purine Y= pyrimidine. Dotted lines denote sites in the D loop and variable loop regions where varying numbers of nucleotides are found in different tRNAs. 

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