Synthesis translocation and

HARTMANN, T., EHMKE, A., EILERT, U., VON BORSTEL, K., THEURING, C., Sites of synthesis, translocation and accumulation of pyrrolizidine alkaloid N-oxides in Senecio vulgaris L Planta, 1989,177,98-107. 

Hartmann, T., A. Ehmke, U. Eilert, K. von Borstel, and C. Theuring, Sites of synthesis, translocation, and accumulation of pyrrolizidine alkaloid V-oxides in Senecio vulgaris L., Planta, 177, 98-107 (1989). 

Hartmann T, Witte L, Oprach F, Toppel G (1986) Reinvestigation of the alkaloid composition of Atropa belladonna plants, root cultures, and cell suspension. Planta Med 52 390-395 Hartmann T, Ehmke A, EUert U, v Borstel K, Theuring C (1989) Sites of synthesis, translocation and accumulation of pyrroUzidine alkaloid V-oxides in Senecio vulgaris. Planta 177 98-107 Hashimoto T, Yamada Y (1994) Alkaloid biogenesis molecular aspects. Aim Rev Plant Mol Biol 45 257-285... 

Change of an alkaloid spectrum in a plant organ during its development often indicates at least one phenomenon de novo synthesis, translocation, and degradation (e.g., tabersonine and the pair dehydroaspidospermidine-vincadifformine on page 217). 

Fig. 8.4 Outline of the main events in protein synthesis initiation, elongation, translocation and termination. AUG is an initiation codon on the mRNA it codes for Af-fomiylmelhionine and initiates the formation of the 70S rihosome. UAG is a termination codon it does not code for any amino acid and brings about termination of protein synthesis.

Puromycin, made by the mold Streptomyces al-boniger, is one of the best-understood inhibitory antibiotics. Its structure is very similar to the 3 end of an aminoacyl-tRNA, enabling it to bind to the ribosomal A site and participate in peptide bond formation, producing peptidyl-puromycin (Fig. 27-31). However, because puromycin resembles only the 3 end of the tRNA, it does not engage in translocation and dissociates from the ribosome shortly after it is linked to the carboxyl terminus of the peptide. This prematurely terminates polypeptide synthesis. 

A unique feature of the F/V/A-ATPases is that they are rotary molecular motor enzymes. This has been shown by experiment for members of the F-and V-ATPase subfamilies and is generally assumed to be true for the closely related A-ATPases as well. The two enzymatic processes, ATP synthesis/hydrolysis and ion translocation, are coupled via a rotational motion of a central domain of the complex (the rotor) relative to a static domain (the stator). The A-, F-, and V-ATPases represent the smallest rotary motors found in the living cell so far. Most of what we know about the structure and mechanism of these microscopic energy converters comes from studies conducted with the F-ATPase. In the following review, current structural knowledge for all three members of the family of F-, V-,... 

SANDER, H., HARTMANN, T., Site of synthesis, metabolism and translocation of senecionine N-oxide in cultured roots of Senecio erucifolius. Plant Cell Tissue Organ Cult., 1989,18, 19-32. 

DCCD inhibits proton translocation through the F subunit of the ATP synthase. Thus, the value of A/xh increases to a point where proton translocation, and hence electron transport, becomes thermodynamically unfavorable. In addition, DCCD inactivates the ATP synthesis function of the ATP synthase. The uncoupler. 2,4-dinitrophenol, renders the inner mitochondrial membrane permeable to protons, leading to a decrease in the value of A/jih< and restoration of electron transport. However, 2,4-dinitrophenol cannot restore the activity of the DCCD-treated ATP synthase. 

The processes of prepropolypeptide synthesis, translocation, proteolytic processing and non-proteolytic modification can be enzymatically defined. These definitions are continuing to be developed and clarified. There are limited reports on insect neuropeptide processing (101.102. but these investigations should increase rapidly with the identification of precursor sequences via molecular genetics. The identification of processing enzymes, both proteolytic and non-proteolytic, will further open whole new areas for exploration. 

Brand, M. D., 1977, The stoichiometric relationships between electron transport, proton translocation and adenosine triphosphate synthesis and hydrolysis in mitochondria, Biochem. Soc. Trans. 5 1615nl620. 

The carrier protein facilitating Pj and phosphate ester transport is of particular interest in leaves in connection with carbon processing - i.e., the synthesis, transport and degradation of carbohydrate, all of which occur in the cytosol [51]. This metabolite carrier, called the phosphate translocator, is a polypeptide with a molecular mass of 29 kDa and is a major component of the inner envelope membrane [52,53]. The phosphate translocator mediates the counter-transport of 3-PGA, DHAP and Pj. The rate of Pj transport alone is three orders of magnitude lower than with simultaneous DHAP or 3-PGA counter-transport [54]. Consequently operation of the phosphate translocator keeps the total amount of esterified phosphate and Pj constant inside the chloroplast. Significantly, the carrier is specific for the divalent anion of phosphate. 

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