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1.
Elimination,Replacement and Isomerization Reactions by Intact Cells Containing Tyrosine Phenol Lyase
Hitoshi Enei Hiroshi Matsui Shinji Okumura Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(11):1869-1876
Tyrosine phenol lyase catalyzes a series of α,β-elimination, β-replacement and racemization reactions. These reactions were studied with intact cells of Erwinia herbicola ATCC 21434 containing tyrosine phenol lyase.Various aromatic amino acids were synthesized from l-serine and phenol, pyrocatechol, resorcinol or pyrogallol by the replacement reaction using the intact cells. l(d)-Tyrosine, 3,4-dihydroxyphenyl-l(d)-alanine (l(d)-dopa), l(d)-serine, l-cysteine, l-cystine and S-methyl-l-cysteine were degraded to pyruvate and ammonia by the elimination reaction. These amino acids could be used as substrate, together with phenol or pyrocatechol, to synthesize l-tyrosine or l-dopa via the replacement reaction by intact cells. l-Serine and d-serine were the best amino acid substrates for the synthesis of l-tyrosine or l-dopa. l-Tyrosine and l-dopa synthesized from d-serine and phenol or pyrocatechol were confirmed to be entirely l-form after isolation and identification of these products. The isomerization of d-tyrosine to l-tyrosine was also catalyzed by intact cells.Thus, l-tyrosine or l-dopa could be synthesized from dl-serine and phenol or pyrocatechol by intact cells of Erwinia herbicola containing tyrosine phenol lyase. 相似文献
2.
Nobuyoshi Esaki Hidehiko Tanaka Edith Wilson Miles Kenji Soda 《Bioscience, biotechnology, and biochemistry》2013,77(12):2861-2864
The α2β2 complex of tryptophan synthase from Escherichia coli catalyzes β-replacement reactions of l-serine and its derivatives (e.g., β-chloro-l-alanine and O-methyl-Dl-serine) with various alkanethiols. The products from thiobenzyl alcohol and ethanethiol were isolated to demonstrate the enzymatic synthesis of the corresponding S-substituted l-cysteines. Reactivities of various S-substituent donors were examined, and thiols such as thiobenzyl alcohol, 1-propanethiol and 1-butanethiol were found to be much more efficient substituent donors than the physiological substrate, indole. In addition, tryptophan synthase catalyzes β-replacement reactions of l-threonine with thiols to form the corresponding S-substituted β-methylcysteines, which are also produced by β-addition reactions of l-vinylglycine with thiols. These enzymatic reactions facilitate the synthesis of various sulfur-containing amino acids. 相似文献
3.
Hidehiko Kumagai Hideyuki Suzuki Hiroki Shigematsu Tatsurokuro Tochikura 《Bioscience, biotechnology, and biochemistry》2013,77(9):2481-2487
An enzyme that catalyzes the synthesis of S-carboxymethyl- l-cysteine from 3-chloro- l-alanine (3-Cl-Ala) and thioglycolic acid was found in Escherichia coli W3110 and was designated as S- carboxymethyl-l-cysteine synthase. It was purified from the cell-free extract to electrophoretic homogeneity and was crystallized. The enzyme has a molecular weight of 84,000 and gave one band corresponding to a molecular weight of 37,000 on SDS-polyacrylamide gel electrophoresis. The purified enzyme catalyzed the β-replacement reactions between 3-CI-AIa and various thiol compounds. The apparent Km values for 3-Cl-Ala and thioglycolic acid were 40 mM and 15.4 mM. The enzyme showed very low activity as to the α,β-elimination reaction with 3-Cl-Ala and l-serine. It was not inactivated on the incubation with 3-Cl-Ala. The absorption spectrum of the enzyme shows a maximum at 412 nm, indicating that it contains pyridoxal phosphate as a cofactor. The N-terminal amino acid sequence was determined and the corresponding sequence was detected in the protein sequence data bank, but no homogeneous sequence was found. 相似文献
4.
Tomoyoshi Iwatsubo Kiyoshi Sekiguchi Kunio Kurata Tomio Tada Kenji Iki Hiroki Nakagawa 《Bioscience, biotechnology, and biochemistry》2013,77(6):1243-1244
β-Chloro-l-alanine was catalytically converted to pyruvate, ammonia and chloride by α-aminoisobutyrate (AIB) decomposing enzyme (α, β elimination), which was synchronously inactivated. There was a linear relationship between α, β elimination and inactivation. With apoenzyme, neither α, β elimination nor inactivation occurred. These facts suggest that α, β elimination is dependent on pyridoxal 5′-phosphate, and inactivation cooperates with α, β elimination (syncatalytic inactivation). But it seemed that d-form of β-chloroalanine was not a substrate for AIB decomposing enzyme, because just half amount of β-chloro-dl-alanine was decomposed to pyruvate by the enzyme.An identical active site for each of following three reactions were shown by the fact that AIB decomposing activity, transamination activity and α, β elimination activity were lost in parallel. From a kinetic study, the affinity of the enzyme toward β-chloro-l-alanine was shown to be higher than that toward AIB or l-alanine. The turnover number, about 8,000, of α, β elimination during the inactivation of one mol of the enzyme was much larger than that of d-amino acid transaminase or alanine racemase. 相似文献
5.
Yoshikazu Izumi Hiroshi Morita Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1327-1333
7-Keto-8-aminopelargonic acid synthetase (KAPA synthetase) which catalyzes the formation of KAPA from pimelyl CoA and l-alanine, and is involved in biotin biosynthesis, was partially purified from a cell-free extract of Bacillus sphaericus by a procedure involving ammonium sulfate fraction ation, protamine treatment, and DEAE-cellulose column chromatography. The reaction product was bioautographically confirmed to be KAPA. Some properties of the enzyme were also investigated. Among the amino acids, only l-alanine was active as a substrate, condensing with pimelyl CoA, The reaction required pyridoxal phosphate but the other vitamin B6 compounds were inert. Typical inhibitors of pyridoxal phosphate enzymes showed marked inhibition to the reaction. Various amino acids such as l-cysteine, glycine, d-alanine, l-serine, l-histidine, and d-histidine were also found to be inhibitory. 相似文献
6.
Hidehiko Kumagai Nobukazu Kashima Hiroshi Torii Hideaki Yamada Hitoshi Enei Shinji Okumuea 《Bioscience, biotechnology, and biochemistry》2013,77(3):472-482
Crystalline tyrosine phenol lyase was prepared from the cell extract of Erwinia herbicola grown in a medium supplemented with l-tyrosine. The crystalline enzyme was homogeneous by the criteria of ultracentrifugation and acrylamide gel electrophoresis. The molecular weight was determined to be approximately 259,000. The crystalline enzyme catalyzed the conversion of l-tyrosine into phenol, pyruvate and ammonia, in the presence of added pyridoxal phosphate. The enzyme also catalyzed pyruvate formation from d-tyrosine, S-methyl-l-cysteine, 3, 4-dihydroxyphenyl-l-alanine, l- and d-serine, and l- and d-cysteine, but at lower rates than from l-tyrosine. l-Phenyl-alanine, l-alanine, phenol and pyrocatechol inhibited pyruvate formation from l-tyrosine.Crystalline tyrosine phenol lyase from Erwinia herbicola is inactive in the absence of added pyridoxal phosphate. Binding of pyridoxal phosphate to the apoenzyme is accompanied by pronounced increase in absorbance at 340 and 425 mμ. The amount of pyridoxal phosphate bound to the apoenzyme was determined by equilibrium dialysis to be 2 moles per mole of enzyme. Addition of the substrate, l-tyrosine, or the competitive inhibitors, l-alanine and l-phenyl-alanine, to the holoenzyme causes appearance of a new absorption peak near 500 mμ which disappears as the substrate is decomposed but remains unchanged in the presence of the inhibitor. 相似文献
7.
Kyoko Noda 《Bioscience, biotechnology, and biochemistry》2017,81(2):343-349
Pyrrolothiazolate formed by the Maillard reaction between l-cysteine and d-glucose has a pyrrolothiazole skeleton as a chromophore. We searched for a Maillard pigment having a pyrrolooxazole skeleton formed from l-threonine or l-serine instead of l-cysteine in the presence of d-glucose. As a result, two novel yellow pigments, named pyrrolooxazolates A and B, were isolated from model solutions of the Maillard reaction containing l-threonine and d-glucose, and l-serine and d-glucose, respectively, and identified as (2R,3S,7aS)-2,3,7,7a-tetrahydro-6-hydroxy-2,5,7a-trimethyl-7-oxo-pyrrolo[2,1-b]oxazole-3-calboxylic acid and (3S,7aS)-2,3,7,7a-tetrahydro-6-hydroxy-5,7a-dimethyl-7-oxo-pyrrolo[2,1-b]oxazole-3-calboxylic acid by instrumental analyses. These compounds were pyrrolooxazole derivatives carrying a carboxy group, and showed the absorption maxima at 300–360 nm under acidic and neutral conditions and at 320–390 nm under alkaline conditions. 相似文献
8.
Yoshikazu Izumi Kuninori Sato Yoshiki Tani Koichi Ogata 《Bioscience, biotechnology, and biochemistry》2013,77(6):1335-1340
The 7-keto-8-aminopelargonic acid (KAPA) synthetase activities of cell-free extracts from various bacteria were investigated. The experiments on the substrate specificity of KAPA synthetase, using crude cell-free extracts from bacteria having high enzyme activity, showed that l-serine and pyruvic acid could replace l-alanine, but that, when the enzyme was partially purified, these compounds were not effective. Many kinds of amino acids such as l-cysteine, l-serine, d-alanine, glycine, d-histidine, and l-histidine, inhibited the enzyme activity. This inhibition was found to be competitive with l-alanine. Pyridoxal 5′-phosphate, which is a cofactor of the enzyme, also inhibited the enzyme activity at high concentrations. The repression of KAPA synthetase by biotin occurred in Bacillus subtilis and B. sphaericus but not in Micrococcus roseus and Pseudomonas fluorescens, even at a concentration of 1000 mµg per ml of biotin. 相似文献
9.
Hajime Yoshida Keizo Hanada Hisakazu Ohsawa Hidehiko Kumagai Hideaki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(4):1035-1042
Biosynthetic threonine deaminase was purified to an apparent homogeneous state from the cell extract of Proteus morganii, with an overall yield of 7.5%. The enzyme had a s020,w of 10.0 S, and the molecular weight was calculated to be approximately, 228,000. The molecular weight of a subunit of the enzyme was estimated to be 58,000 by sodium dodecyl sulfate gel electrophoresis. The enzyme seemed to have a tetrameric structure consisting of identical subunits. The enzyme had a marked yellow color with an absorption maximum at 415 nm and contained 2 mol of pyridoxal 5′-phosphate per mol. The threonine deaminase catalyzed the deamination of l-threonine, l-serine, l-cysteine and β-chloro-l-alanine. Km values for l-threonine and l-serine were 3.2 and 7.1 mm, respectively. The enzyme was not activated by AMP, ADP and ATP, but was inhibited by l-isoleucine. The Ki for l-isoleucine was 1.17 mm, and the inhibition was not recovered by l-valine. Treatment with mercuric chloride effectively protected the enzyme from inhibition by l-isoleucine. 相似文献
10.
Sonoe Ochiai Yanagi Masako Kito Maria A. M. Galeazzi 《Bioscience, biotechnology, and biochemistry》2013,77(10):2561-2563
The acylated, amidated and esterified derivatives of N-acetylglucosaminyl-α(1 → 4)-N-acetylmuramyl tri- and tetrapeptide were synthesized and examined as to their protective effect on pseudomonal infection in the mouse and pyrogenicity in the rabbit. Modifications of the terminal end function of the peptide moieties in their molecules caused enhancement of resistance to pseudomonal infection and reduction of pyrogenicity. Among the compounds tested, sodium N-acetylglucosaminyl-β(1 → 4)-N-acetylmuramyl-l-alanyl-d-isoglutaminyl-(l)-stearoyl-(d)-meso-2,6-diaminopimelic acid-(d)-amide and sodium N-acetylglucosaminyl-β(1 → 4)-N-acetylmuramyl-l-alanyl-d-isoglutaminyl-(l)-stearoyl-(d)-meso-2,6-diaminopimelic acid-(d)-amide-(l)-d-alanine were found to be advantageous and conceivably worthwhile for further investigation as immunobiologically active compounds. 相似文献
11.
Kenji Sakai Takashi Tachki Hidehiko Kumagai Tatsurokuro Tochkura 《Bioscience, biotechnology, and biochemistry》2013,77(9):2287-2293
Two β-d-glucosidases were purified to homogeneity from Bifidobacterium breve 203: one ( β-d-glucosidase I; molecular weight, 96,000) showed reactivity toward p-nitrophenyl (p-NP) β-d-fucoside, 74% of that to p-NP β-d-glucoside, and the other ( β-dglucosidase II; molecular weight, 450,000) did not. They also differed in their thermal and pH stabilities. Laminaribiose, cellobiose and gentiobiose were hydrolyzed by β-d-glucosidase I, with 53%, 34% and 3% of the reactivity in the case of p-NP β-d-glucoside, and by β-dglucosidase II, with 53%, 6% and 107% of the reactivity. The reaction of β-dglucosidase I with p-NP β-dfucoside was enhanced by the addition of glucose and other monosaccharides to the reaction mixture, whereas that with p-NP β-dglucoside was not affected. The activity of β-dglucosidase II with p-NP β-dglucoside was inhibited by glucose. 相似文献
12.
The electrophoretically homogeneous glucomannan isolated from konjac flour was composed of d-glucose and d-mannose residues in the approximate ratio of 1: 1.6. Controlled acid hydrolysis gave 4-O-β-d-mannopyranosyl-d-mannose, 4-O-β-d-mannopyranosyl-d-glucoseT 4-O-β-d-glucopyranosyl-d-glucose(cellobiose), 4-O-β-d-glucopyranosyl-d-mannose(epicellobiose), O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-glucopyranosyl- (1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose, O-β-d-mannopyranosyl-(1→4)-O-β-d-glucopy- ranosyl-(1→4)-d-mannose and O-β-d-glucopyranosyl-(1→4)-O-β-d-glucopyranosyl-(1→4)-d-mannose. 相似文献
13.
Substrate Specificity of Thermostable D-Alanine-D-alanine ligase from Thermotoga maritima ATCC 43589
《Bioscience, biotechnology, and biochemistry》2013,77(11):2790-2792
D-Alanine-D-alanine ligase (Ddl) and its mutants maintain the biosynthesis of peptidoglycan, and the substrate specificity of Ddls partially affects the resistance mechanism of vancomycin-resistant enterococci. Through investigation of Ddls, Ddl from Thermotoga maritima ATCC 43589 showed novel characteristics, vis. thermostability up to 90 °C and broad substrate specificity toward 15 D-amino acids, particularly D-alanine, D-cysteine, and D-serine, in that order. 相似文献
14.
Kimio Sugiyama Yasuo Kushima Keiichiro Muramatsu 《Bioscience, biotechnology, and biochemistry》2013,77(11):2897-2899
l-Methionine γ-lyase (EC 4.4.1.11) catalyzes α,β-elimination of l-2-amino-3-(N-methylamino)propionic acid and l-2-amino-3-(N-hydroxyethylamino)propionic acid to yield pyruvate, ammonia, and the corresponding amines. These amino acids also undergo the enzymatic β-replacement reaction with thiols to produce the corresponding S-substituted cysteines. Thus, l-methionine γ-lyase cleaves a C-N bond in addition to C-S, C-Se, and C-O bonds at the β position of amino acids by elimination and replacement reactions. A linear relationship between the reactivity, (log(Vmax/Km) and the pKa value of the conjugated acid of the leaving group has been found for Se-methyl-l-selenocysteine, S-methyl-l-cysteine, and O-methyl-l-serine. However, l-2-amino-3-(N-methylamino)propionic acid has shown lower reactivity than that expected from the pKa value of methylammonium ions. 相似文献
15.
Fumio Yagi Kenjiro Tadera Akira Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(10):2985-2990
transglucosylation by a β-d-glucosidase from cycad seeds. These azoxyglycosides, named neocycasin H, I, and J, were identified as O-β-d-glucopyranosyl-(1→4)-O-β-d-glucopyranosyl-(l→3)-O-β-d-glucopyranoside of methylazoxymethanol (MAM), O-β-d-glucopyranosyl-(1→3)-[O-β-d-glucopyranosyl-(1→6)]-O-β-d-glucopyranoside of MAM, and O-β-d-glucopyranosyl-(1→3)-[O-β-d-xylopyranosyl-(1→6)]-O-β-d-glucopyranoside of MAM, respectively. On the basis of their structures, the mechanism of the formation of these neocycasins is also discussed. 相似文献
16.
Fumio Hishinuma Kazuo Izaki Hajime Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(13):2050-2058
l-Alanine adding enzymes from Bacillus subtilis and Bacillus cereus which catalyzed l-alanine incorporation into UDPMurNAc were partially purified and the properties of the enzymes were examined. The enzyme from B. subtilis was markedly stimulated by reducing agents including 2-mercaptoethanol, dithiothreitol, glutathione and cysteine. Mn2+ and Mg2+ activated l-alanine adding activity and their optimal concentrations were 2 to 5 mm and 10 mm, respectively. The optimum pH was 9.5 and the Km for l-alanine was 1.8×10?4m. l-Alanine adding reaction was strongly inhibited by p-chloromercuribenzoate and N-ethyl-maleimide. Among glycine, l- and d-amino acids and glycine derivatives, glycine was the most effective inhibitor of the l-alanine adding reaction. The enzyme from B. cereus was more resistant to glycine than that from B. subtilis. Glycine was incorporated into UDPMurNAc in place of l-alanine, and the Ki for glycine was 4.2×l0?3m with the enzyme from B. subtilis. From these data, the growth inhibition of bacteria by glycine is discussed. 相似文献
17.
Fumio Hishinuma Kazuo Izaki Hajime Takahashi 《Bioscience, biotechnology, and biochemistry》2013,77(11):1577-1586
Growth of various microorganisms in media containing high concentrations of glycine or d-amino acids was examined. Susceptibilities to glycine or d-amino acids differed among microorganisms, and the differences in susceptibility have no direct relation with Gram staining, morphological forms, and aerobic or anaerobic nature of the organisms. Certain glycine-resistant bacteria tested, which included Bacillus cereus, Staphylococcus aureus and Serratia marcescens, exhibited relatively high oxidative activities towards glycine. The inhibition of the growth of Escherichia coli by either glycine or d-amino acids, which included d-threonine, d-alanine and d-lysine, was reversed by l-alanine, partialy by l-serine, and not by l-lysine or l-threonine. These results suggest that the growth inhibition of microorganisms by d-amino acids was similar to that by glycine. The incorporation of l-alanine into E. coli cells which were preincubated with glycine was less than those of preincubated without glycine. Particularly, the incorporation into the cell wall fraction was most susceptible to glycine. An additive effect of penicillin and glycine was observed in the inhibition of cell wall biosynthesis as determined by the intracellular accumulation of N-acetylamino sugar compounds. 相似文献
18.
Koya Kawano Kazuki Sakai Hiroji Sato Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):1999-2002
During an examination of components contributing to the bitter taste of asparagus bottom cut (Asparagus officinalis L.), two new furostanol saponins were isolated from roots extractives. Their chemical structures were established as 5β-furostane-3β,22,26 triol-3-O-β-d-glucopyranosyl (1→2)-β-d-glucopyranoside 26-O-β-d-glucopyranoside and 5β-furostane-3β,22,26 triol-3-O-β-d-glucopyranosyl (1→2) [β-d-xylopyranoxyl (1→4)]-β-d-glucopyranoside 26-O-β-d-glucopyranoside respectively. 相似文献
19.
A glucomannan isolated from konjac flour was hydrolyzed with commercially available crude and purified cellulases. The following oligosaccharides were isolated from the hydrolyzate and identified: (a) 4-O-β-d-mannopyranosyl-d-monnose (b) 4-O-β-d-mannopyranosyl-d-glucose (c) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose (d) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (e) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose (f) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (g) O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-glucose (h) 4-O-β-d-glucopyranosyl-d-glucose(cellobiose) (i) 4-O-β-d-glucopyranosyl-d-mannose (epicellobiose) (j) O-β-d-glucopyranosyl-(1→4)-O-β-d-mannopyranosyl-(1→4)-d-mannose. Of these saccharides, (h), (i) and (j) were isolated from the hydrolyzate by purified cellulase, while (g) was isolated from the hydrolyzate by crude cellulase. The others were all present in the hydrolyzates both by crude and by purified cellulases. 相似文献
20.
Rubusoside derivatives by transgalactosylation of various β-galactosidases were isolated and their structures were analyzed. Escherichia coli β-galactosidase produced mainly 13-O-β-d-glucosyl-19-O-[β-d-galactosyl-(1→6)-β-d-glucosyl]-steviol (RGal-2). Bacillus circulans β-galactosidase produced mainly 13-O-β-d-glucosyl-19-O-[β-d-galactosyl-(1→4)-β-d-glucosyl]-steviol (RGal-1a) in the early stage of the reaction and then produced 13-O-[β-d-galactosyl-(1→4)-β-d-glucosyl]-19-O-β-d-glucosyl-steviol (RGal-1b). With decreasing the amount of these products (RGal-1a and RGal-1b), RGal-2 was produced. 相似文献