Precursors processes

Steiner DF et al The new enzymology of precursor processing en-doproteases. J Biol Ghem 1992 267 23435. 

Up to now, the pectinolytic enzymes of E. chrysanthemi that have been detected were extracellular secreted enzymes (PelA, B, C, D, E, L, exo-Peh and PemA), periplasmic (exo-Pel), or cytoplasmic (OGL) proteins (1, 5). In contrast, PemB is an outer membrane pectinolytic enzyme. To our knowledge it is the first pectinase characterised as a membrane protein. We presented several lines of evidence showing that PemB is a lipoprotein (i) Its N-terminal sequence has the characteristics of lipoprotein signal sequences, (ii) PemB is synthesised as a high molecular weight precursor processed into a lower molecular weight mature form, (iii) Palmitate, the most prevalent fatty acid in bacterial lipoproteins (12), is incorporated into PemB. 

Wagner SL, Munoz B. Modulation of amyloid B-protein precursor processing as a means of retarding progression of Alzheimer s disease. J Clin Invest 1999 104 1329-1332. 

An overview of the precursors, process chemistry, and relative advantages and disadvantages of the three principal methods of inorganic electronic thin film preparation is shown in Table 2.1. Generally, sol-gel methods offer the greatest control over the nature of the solution precursor species, but they have involved... 

If the process is a new design, the experience requirement may be satisfied by bringing in a person from a sister plant or from a similar or precursor process. In addition, at least one member of the team must be knowledgeable in the hazard analysis methodology being used (see note at the end of Section 1.0). 

I. Murase, T. Ohnishi, T. Noguchi, and M. Hirooka, Highly conducting poly(phenylene vinylene) derivatives via soluble precursor process, Synth. Met., 17 639-644, 1987. 

Heinemeyer, W., Fischer, M., Krimmer, T., Stachon, U., and Wolf, D. H. The active sites of the eukaryotic 20S proteasome and their involvement in subunit precursor processing. J. Biol. Chem. 1997, 272, 25200— 25209. 

This same increase in the number of isomers with molecular weight also applies to the other molecular types present. Since the molecular weights of the molecules found in petroleum can vary from that of methane (CH4 molecular weight = 16) to several thousand (Speight, 1999, and references cited therein), it is clear that the heavier nonvolatile fractions can contain virtually unlimited numbers of molecules. However, in reality the number of molecules in any specified fraction is limited by the nature of the precursors of petroleum, their chemical structures, and the physical conditions that are prevalent during the maturation (conversion of the precursors) processes. 

The option "Modify precursor" (Process menu) permits you to modify the position of the atoms in any precursor on the synthesis tree. It has been introduced because, when the program disconnects a molecule, partially overlapping atoms may appear, or the precursor generated may come up in an impossible conformation. 

Though in competition with other analytical techniques, CE has proven its potential and necessity to be used for the characterization of small-molecule pharmaceuticals. Due to the versatility of the system, CE can be applied for the determination of physicochemical properties, identification, purity and stability analysis, and cleaning verification of the drug substance, its precursors, process chemicals, the drug product, and its excipients. 

Hybrid Inorganic/Organic Polymers with Nanoscale Building Blocks Precursors, Processing, Properties and Applications , K.-H. Haas and K. Rose, Rev. Adv. Mater. Sci. 5, 47-52 (2003). 

In precursor processing, shelf life is rarely a problem as noncovalent bonding interactions between molecules and solvent content define processability. Furthermore, atomic mixing and multimetallic compounds are readily accessible as will be amply demonstrated below. Thus, there is recent interest in developing oxide precursors for processing... 

McCormick J., Lim I. and Nichols R. (1999) Neuropeptide precursor processing detected by triple immunolabeling. Cell Tissue Res. 297, 197-202. 

An aminopeptidase activity has been demonstrated to cleave the N-terminal Arg residue from bovine /3-lipotropin [49]. This activity appears to be specific for basic residues, but is blocked by the presence of proline residues on the carboxyl side of the N-terminal arginine [22]. However, it is not yet clear whether this aminopeptidase is involved in precursor processing in situ. 

Translation of presecretory proteins Post-translational precursor processing Removal of the signal peptide sequence Signal peptidase activity... 

Nicot A, Bidard JN, Kitabgi P, Lhiaubet AM, Masuo Y, Palkovits M, Rostene W, Berod A (1995a) Neurotensin and neuromedin N brain levels after fornix transsection evidence for an efficient neurotensin precursor processing in subicular neurons. Brain Res 702 279-283. 

Steinee, D. F. (2002). The prohormone convertases and precursor processing in protein biosynthesis. In Dalbey, R. E., Sigman, D. S. (Eds.), The enzymes co-and post-translational proteolysis of proteins, Vol. XXII. Academic, San Diego. 

These materials are extremely hard and wear resistant up to high temperatures (800 °C) and are used as high-speed cutting tools. They contain finely dispersed (l-3 J,m size) particles ofW, Ti, or Ta carbides (primarily WC) in a cobalt binder matrix (70 97.5% carbide). The direction of further development here is to produce and compound increasingly fine particulates, for example, by use of chemical precursor processes. ... 

An important application of the polymerized alkoxide precursor process is the formation of silica gels, carried out in water-ethyl alcohol solutions to which tetraethylorthosilicate Tetraethylorthosilicate TEOS, is added. A small amount of a mineral acid such as HCl or HNO3 serves as a catalyst for the reaction that involves the formation of hydroxy-orthosilicate intermediate. 

Rockwell NC, Krysan DJ, Komiyama T, Fuller RS. Precursor processing by Kex2/Furin proteases. Chem. Rev. 2002 102 4525-4548. 

Figure 28.23. Transfer RNA Precursor Processing. The conversion of a yeast tRNA precursor into a mature tRNA requires the removal of a 14-nucleotide intron (yellow), the cleavage of a 5 leader (green), and the removal of UU and the attachment of CCA at the 3 end (red). In addition, several bases are modified.

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