In vitro synthesis

Very Htfle data are available regarding effects of anaboHc steroid implants on the Hpid metaboHsm in growing mminants. Lipogenic enzyme activity and fatty acid synthesis in vitro were elevated in subcutaneous adipose tissue from bulls implanted with estradiol (44), which may account for the increase in fat content of carcasses reported in some studies. TBA implants have no effect on Hpogenesis in intact heifers, and only tend to reduce Hpogenic enzyme activities in ovariectomized heifers (45). 

Sirover, MA, Loeb LA. 1976. Infidelity of DNA synthesis in vitro Screening for potential metal mutagens or carcinogens. Science 194 1434-1436. 

Enzymatic synthesis in vitro (outside cells) via biosynthetic pathways... 

Chemical synthesis in vitro (in test tubes) via non-biosynthetic pathways catalyzed by an isolated enzyme... 

ARCAs are incorporated into RNA exclusively in the correct orientation to an extent that is similar to the standard cap (see previously), which makes them potentially useful compounds in terms of increasing translational efficiency when incorporated into RNA. Similarly, they should be effective for inhibiting protein synthesis as free analogs. To test the influence of the ARCAs on protein synthesis in vitro, we use the microccocal nuclease treated rabbit reticulocyte lysate system (RRL system) optimized for cap-dependent translation (Cai et al., 1999). Highly cap-dependent translation is achieved at 100 mM potassium acetate and 1.4 mM magnesium chloride. 

Tadayoni, B.M., Friden, P.M., Walus, L.R., and Musso, G.F. (1993) Synthesis in vitro kinetics, and in vivo studies on protein conjugates of AZT Evaluation as a transport system to increase brain delivery. Bioconjugate Chem. 4, 139-145. 

Gasperi-Campani, Anna, Luigi Barbieri, Enzo Lorenzoni, Lucio Montanaro, Simonetta Sperti, Eugenio Bonetti, and Fiorenzo Stirpe. "Modeccin, the Toxin of Adenia digitata Purification, Toxicity and Inhibition of Protein Synthesis In Vitro." Biochemical Journal 174 (1978) 491-96. 

Independently, if these cytokines can exert their bone resorption functions without RANKL, they all stimulate the production of RANKL for stromal/OB cells, and conversely RANKL is able to increase IL-1 and TNF-a synthesis in vitro. To complicate this scenario, these systems of cytokines connect with the network of systemic hormones, such as PTH, PTH-related protein (PTHrP), vitamin D3, estrogens, androgens, glucocorticoids, and T4, since the hormones regulate the production of many of these cytokines by stromal/OB cells (Manolagas et al. 1995 Bellido et al. 1995 Lakatos et al. 1997). 

In other studies, mast cells have been shown to be abundant in the marrow of osteoporotic patients, and heparin, which is contained within the secretory granules of connective tissue (peritoneal)-type mast cells, has been shown to enhance bone resorption and to inhibit bone-cell replication and collagen synthesis in vitro [130]. Moreover, heparin is known to bind growth factors such as fibroblast growth factor and may therefore be important in limiting their availability [134], Taken together, these various studies suggest a possible involvement of mast cells in the homeostasis of bone, but much more work is needed before any definitive conclusions can be drawn. 

PtCl2(Me2N(CH2)3PPh2)2] terminates DNA synthesis in vitro more efficiently than cisplatin (136). 

Assays for DNA Effects DNA damage and repair unscheduled DNA synthesis in vitro / ... 

It is interesting to note that serine peptidases can, under special conditions in vitro, catalyze the reverse reaction, namely the formation of a peptide bond (Fig. 3.4). The overall mechanism of peptide-bond synthesis by peptidases is represented by the reverse sequence f-a in Fig. 3.3. The nucleophilic amino group of an amino acid residue competes with H20 and reacts with the acyl-enzyme intermediate to form a new peptide bond (Steps d-c in Fig. 3.3). This mechanism is not relevant to the in vivo biosynthesis of proteins but has proved useful for preparative peptide synthesis in vitro [17]. An interesting application of the peptidase-catalyzed peptide synthesis is the enzymatic conversion of porcine insulin to human insulin [18][19]. 

S. Benzaria, H. Pelicano, R. Johnson, G. Maury, J. L. Imbach, A. M. Aubertin, G. Obert, G. Gosselin, Synthesis, in vitro Antiviral Evaluation, and Stability Studies of Bis(S-acyl-2-thioethyl) Ester Derivatives of 9-[2-(Phosphonomethoxy)ethyl]adenine (PMEA) as Potential PMEA Prodrugs with Improved Oral Bioavailability , J. Med. Chem. 1996, 39, 4958-4965. 

Easton N, Fry J, O Shea E, Watkins A, Kingston S, et al. 2003. Synthesis, in vitro formation, and behavioural effects of glutathione regioisomers of alpha-methyldopamine with relevance to MDA and MDMA (ecstasy). Brain Res 987 144-154. 

NT451 Ollson, E., A. Holth, E. Kumlin, L. NT462 Bohlin, and I. Wahlberg. Structure-related inhibiting activity of some tobacco cembranoids on the prostaglandin synthesis in vitro. Planta Med 1993 59(4) 293-295. 

Bilgin N, Ehrenberg M, Claesens F, Pahverk H (1998) Measurement of rate of protein synthesis in vitro. 

Usdin, K. and Woodford, K.J. (1995) CGG repeats associated with DNA instability and chromosome fragility form structures that block DNA synthesis in vitro. Nucl Acids Res 23 4202-4209. 

In one study, 2-nitropropane induced unscheduled DNA synthesis in vitro in hepatocytes from three of six people. In human peripheral lymphocytes, 2-nitropropane induced sister chromatid exchanges and chromosomal aberrations in the presence of an exogenous metabolic system. 

Ribosomes were discovered by electron micros-copists examining the structure of the endoplasmic reticulum using ultrathin sectioning techniques. Their presence in cells was established by 1956, and the name ribosome was proposed in 1957. At first it was difficult to study protein synthesis in vitro using isolated ribosomes. No net synthesis could be detected until Hoagland and associates measured the rate of incorporation of 14C-labeled amino acids into protein.26 This sensitive method permitted measurement of very small amounts of protein synthesis in cell-free preparations from rat liver and paved the way toward studies with ribosomes themselves. 

These observations are consistent with the conclusion that auxin treatment leads to the synthesis of BS cellulase, which then accumulates in smooth ER vesicles. There is direct evidence that the synthesis occurs in rough ER vesicles (11). Cellulase activity was shown (25) to increase in RNA-rich pea microsomes, provided these were isolated from auxin-treated tissue, when the preparations were incubated with ingredients necessary for carrying out protein synthesis in vitro. Messenger RNA (mRNA) from these microsomes has been translated in a different ribo-somal system and shown to synthesize BS cellulase protein (II). Thus, it is legitimate to use the term "induction to apply to the ability of auxin to evoke the appearance of mRNA for BS cellulase. 

Mundy, J., Hejgaard, J., Hansen, A., Hallgren, L., Jprgensen, K. Munck, L. (1986). Differential synthesis in vitro of barley aleurone and starchy endosperm proteins. Plant Physiology 81, 630-6. 

Talib, S., and J.E. Hearst. 1983. Initiation of RNA synthesis in vitro by vesicular stomatitis virus Single internal initiation in the presence of aurintricarboxylic acid and vanadyl ribonucleoside complexes. Nucleic Acids Res 11 7031. 

In more recent investigations, the assumed multienzyme involved in cyclosporin A biosynthesis could be isolated from T. inflatum. A partially purified enzyme fraction was indeed capable of forming enzyme-substrate complexes by thioester linkage. Although de novo synthesis (in vitro) of cyclosporin A has not yet been achieved, the formation of a partial sequence, namely, the diketopiperazine cyclo(DAla-MeLeu), from D-alanine and L-leucine was observed under consumption of ATP and S-adenosyl-L-methio-nine [25]. 

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