Cysteine aminoethylated

Refs. 21, 22, 155. Abbreviations AHV, a-amino-(3-hydroxyvaleric acid Horn, L-homoserine AEG, (3 -(2-aminoethyl)-L-cysteine ppc, phosphoenolpymvate carboxylase the strain improvement largely depends on the transduction technology sensitive resistant —, auxotroph or deficient , leaky auxotroph +, prototrophic revertant. Table 7. Amino Acid Production from Hydrocarbons ... 

Abbreviations Horn, homoserine AEG, 3 -(2-aminoethyl)-L-cysteine resistant —, auxotroph. ... 

S., Simultaneous determination of urinary cystathionine, lanthionine, S-(2-aminoethyl)-L-cysteine and their cyclic compounds using liquid chromatography-mass spectrometry with atmospheric pressure chemical ionization, /. Chromatogr. B, 698, 301, 1997. 

In this laboratory, we also include the metal ion chelators EDTA (ethylene diamine tetraacetic acid binds, e.g., Mg2 1 -ions) and EGTA (ethylene glycol-bis(2-aminoethyl)-Al,iV,iV/,iV/,-tetraacetic acid binds, e.g., Ca2+-ions) in our lysis buffers. These agents help prevent phosphatase action (by the metal ion-dependent phosphatase PP2C, which is not inhibited by microcystin-LR), metal (Ca2+) dependent proteinases, and protein kinases, which require divalent cations such as Mg2 1 (and, in some cases, also Ca2+). We also use a mix of proteinase inhibitors that inhibit a broad range of proteolytic enzymes, including serine and cysteine proteinases. 

Thiolsulfonate-containing compounds can react with thiols with release of the sulfonate end of the molecule to yield disulfide derivatives. The modification reagent 2-aminoethyl-2 -aminoethanethiolsulfonate, or AEAETS, reacts with a sulfhydryl with release taurine (2-aminoethanesulfonate) to form a 2-aminoethyl-dithiol derivative (Figure 1.94). AEAETS can be used to block cysteine residues in proteins and form derivatives containing positively charged amines. 

Noteworthy is the labelling of so-called peptide nucleic acids (PNAs). These constitute a class of synthetic macromolecules where the deoxyribose phosphate backbone of DNA is replaced by the pseudo-peptide A/-(2-aminoethyl)glycyl backbone, while retaining the nucleobases of DNA [270,271]. PNAs have been labelled at a terminal cysteine-site using A/-(4-[ F]fluorobenzyl)-2-bromoaceta-mide [272-274], a reagent belonging to another class of thiol-selective reagents. 

Lugli, J. Gaziola, S.A. Azevedo, R.A. Effects of calcium, S-adenosylmethio-nine, S-(2-aminoethyl)-L-cysteine, methionine, valine and salt concentration on rice aspartate kinase isoenzymes. Plant Sci., 150, 51-58 (2000)... 

S-(2-Aminoethyl)-L-cysteine (AEC), H2N-CH2-CH2-S-CH2-CH(NH2)-COOH, a lysine analog, acts as a false feedback inhibitor on aspartokinase, which produces aspartylphosphate from aspartate. The inhibitor simulates, for aspartokinase, the absence of lysine and threonine, and as a consequence the AEC insensitive mutant is no longer inhibited by lysine and threonine. The result was a yield increase from 0 to 16 g L 1. 

Abz was combined with a broad variety of non-fluorescent acceptors such as p-nitrobenzyl for leucine aminopeptidase (Carmel et al., 1977), pNA for trypsin (Bratanova and Petkov, 1987), 4-ni-trophenylalanine [Phe(NC>2)] for HIV protease (Toth and Marshall, 1990), and V-(2,4-di n itrophenyl) ethylenediamine (EDDnp) for thermolysin and trypsin (Nishino et al., 1992). Lecaille et al. (2003) described a FRET quench assay based on a specific substrate for cathepsin K labeled with Abz and EDDnp. This substrate is not cleaved by the other Cl cysteine cathepsins and serine proteases in contrast to methoxycoumarin (Mca)-based substrates described earlier (Aibe et al., 1996 Xia et al., 1999) and merely covered the non-primed site of the scissile bond. The 5-[(2-aminoethyl)amino] naphthalene-l-sulfonic acid (EDANS) compound is a second example of a fluorescence donor historically used for many FRET quench-based protease assays, e.g., in combination with tryptophan as a quencher in an ECE activity assay (Von Geldren et al., 1991). The FRET-1 example in Table 2.2 shows the typical dynamic range that can be achieved with an EDANS/DABCYL-based assay. 

The opposite approach, namely, the creation of additional lysine-like sites for cleavage by trypsin has been used in the conversion of cysteine bonds to /S-( -aminoethyl)-cysteine residues by reaction of the thiol groups with jS-bromoethylamine (Lindley, 1959). Enzymatic degradation of such modified proteins, e.g., reduced and /3-aminoethylated insulin, by the ac-... 

Bonds formed by cysteinyl residues can be made susceptible to tryptic action when the thiol group of the cysteine side chains is reacted with i8-bromoethylamine (Bindley, 1956). The resulting ( -( -aminoethyl)-cysteinyl side chains provide the specificity requirements necessary for tryptic action. One methylene carbon of the lysyl side chain is replaced by a sulfur atom in thioether linkage. Bonds formed by the carboxyl group of this derivative are susceptible to tryptic action. Reduction of... 

Crafting a new breakpoint. Ethyleneimine reacts with cysteine side chains in proteins to form -aminoethyl derivatives. The peptide bonds on the carboxyl side of these modified cysteine residues are susceptible to hydrolysis by trypsin. Why ... 

C4H10CfNO2S methyl L-cysteine hydrochloride 18598-63-5 25.00 1.2321 2 4080 C4H12N20 N-aminoethyl ethanolamine 111-41-1 0.00 1.2186 2... 

Di(j8-carboxy-j8-aminoethyl)-3-amino-4-hydroxyphenylthio-arsinite is obtained by the int(a ac tion of 3-annno-4-hydroxyphenyl-arsinic acid and cysteine hydrochloride it crystallises in line, matted needles,... 

Several specialized silica-based functionalized platinum scavengers such as N-acetyl-L-cysteine, 2-aminoethyl sulfide, 2-mercaptoethyl ethyl sulfide, 3-mercapto-propyl ethyl sulfide, pentaerythritol 2-mercaptoacetate ethyl sulfide and triamine ethyl sulfide amide, developed by Strem Chemicals, are also available. These scavengers are highly stable and available in pure forms, which successfully scavenge platinum metal ions in batch processes. 

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