L-glycine and L-cysteine, exhibit strong inhibition of partial purified PPO of wild pear. The concentration of L-glycine inhibiting PPO activity by 50% (IC ) was 0.8 and 0.5 mM for catechol oxidation and 50 0.75 and 0.5 mM for pyrogallol oxidation at pH 5 and 7, respectively. IC for L-cysteine calculated, 0.6 and 0.35 50 for catechol oxidation and 0.55 and 0.75 mM for pyrogallol oxidation at pH...

To study the fate of L-cysteine and amino acid homeostasis in liver after the inhibition of the trans-sulfuration pathway, rats were treated with propargylglycine (PPG). At 4 h after the administration of PPG, liver cystathionase (EC 4.4.1.1) activity was undetectable, L-cystathionine levels were significantly higher, L-cysteine was unchanged and GSH concentration was significantly lower than v...

Glycerol-stabilised cell extracts of Streptomyces clavuligerus contain an enzyme activity which synthesises ACV from the individual amino acids L-a-aminoadipic acid, t-cysteine and L-valine. Enzyme activity was optimum in reaction mixtures containing 1 mM ATP together with an ATP regenerating system. The ACV synthetase enzyme formed ACV analogs when provided with Lcarboxymethylcysteine in place...

purpose: evaluation of humoral and cellular immune responses of naturally infected dogs against type i (rcpb) (recombinant cycsteine proteinase b), and ii (rcpa) (recombinant cycsteine proteinase a) recombinant cysteine proteinases and c-terminal extension (cte) of leishmania infantum (l. infantum). materials and methods: in this study, fourteen infected dogs (7 with symptoms, 7 asymptomatics)...

Volatile sulfur compounds are key flavor compounds in several cheese types. To better understand the metabolism of sulfur-containing amino acids, which certainly plays a key role in the release of volatile sulfur compounds, we searched the genome database of Lactobacillus casei ATCC 334 for genes encoding putative homologs of enzymes known to degrade cysteine, cystathionine, and methionine. The...

Unger, Leon (University of Illinois, Urbana), and R. D. DeMoss. Metabolism of a proline analogue, l-thiazolidine-4-carboxylic acid, by Escherichia coli. J. Bacteriol. 91:1564-1569. 1966.-Resting cells of Escherichia coli K-12, pregrown in a proline- and thioproline-free medium, oxidize the proline analogue, l-thiazolidine-4-carboxylic acid (l-thioproline), without a lag with the consumption of ...

Among amino acids, cysteine has been widely studied, becoming a standard for molecular self-assembly experiments, because its mercapto group (–SH) allows the formation of self-assembled monolayers (SAMs) on metal surfaces. Dissociative electron attachment (DEA) on L-cysteine SAMs is investigated utilizing a time-of-flight mass spectrometer coupled with a low-energy electron gun. The results sho...

Tryptophanase from Bacillus alvei exhibited the expected spectrum of pyridoxal-5'-phosphate-dependent reactions. It exhibited l-serine dehydratase, S-alkyl-cysteine lyase, and cysteine desulfhydrase activities, as well as the classic tryptophanase reactions (all beta elimination reactions). It also acted as a tryptophan synthetase (beta replacement reactions) using indole plus l-serine or l-cys...

System L amino acid transporters have been shown to be responsible for cellular uptake of S-nitroso-L-cysteine (l-CSNO). In this study, we examined the characteristics of L-CSNO uptake in Xenopus laevis oocytes expressing system L transporters and found that uptake increased only when both 4F2 heavy chain (4F2HC) and either L-type amino acid transporter 1 (LAT1) or LAT2 light chain were coexpre...

The adsorption/desorption behaviour of the thiol/disulfide redox couple, cysteine/cystine, was monitored at a Au(1 1 1) single crystal electrode. The monolayers were formed electrochemically from 0.1 M KClO4 and 0.1 M NaOH solutions containing either the thiol or the disulfide. Distinct features in the adsorption potential were noted. An adsorption peak was observed in the cyclic voltammograms ...