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1.
Summary. The effect of dietary sulfur amino acids on the taurine content of rat blood and tissues was investigated. Three types of
diet were prepared for this study: a low-taurine diet (LTD), normal taurine diet (NTD; LTD + 0.5% Met), and high-taurine diet
(HTD; LTD + 0.5% Met + 3% taurine). These diets had no differing effect on the growth of the rats. The concentration of taurine
in the blood from the HTD- and NTD-fed rats was respectively 1,200% and 200% more than that from LTD-. In such rat tissues
as the liver, the taurine content was significantly affected by dietary sulfur amino acids, resulting in a higher content
with HTD and lower content with LTD. However, little or no effect on taurine content was apparent in the heart or eye. The
activity for taurine uptake by the small intestine was not affected by dietary sulfur amino acids. The expression level of
taurine transporter mRNA was altered only in the kidney under these dietary conditions: a higher expression level with LTD
and lower expression level with HTD.
Received January 8, 2002 Accepted January 18, 2002 Published online August 20, 2002
Authors' address: Dr. Hideo Satsu, Laboratory of Food Chemistry, Department of Applied Biological Chemistry, Graduate School of Agricultural
and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan, Fax: +81-3-5841-8026 E-mail: asatsu@mail.ecc.u-tokyo.ac.jp
Abbreviations: HTD, high-taurine diet; NTD, normal taurine diet; LTD, low-taurine diet; TAUT, taurine transporter; CSA, cysteine sulfinate;
CDO, cysteine dioxygenase; CSAD, cysteine sulfinate decarboxylase; PBS, phosphate-buffered saline; DIDS, 4,4′-diisothiocyanostilbene-2′,2′-disulfonic
acid 相似文献
2.
Summary. Eight analogs 4a-7a and 4b-7b of philanthotoxin (PhTX) from wasp venom and nephilatoxin-8 (NPTX-8) from spider venom whose tyrosine or asparagine linker
is replaced by squaryl (sq) amino acid or 4-amino squaryl (4-asq) amino acid have been synthesized in an efficient manner
via coupling of N-acyl squaryl amino acid intermediate 19 or 26 with the corresponding polyamine part. Preliminary bioassay using crickets revealed that the analogs substituted by glutamate-type
squaryl amino acid-containing NPTX 7a and 7b showed more potent paralytic activities than that of NPTX-8.
Received April 25, 2002 Accepted June 21, 2002 Published online December 18, 2002
Acknowledgement This work was supported by a grant from Research for the Future Program from the Japan Society for the Promotion of Science
(JSPS).
Authors' address: Yasufumi Ohfune, Graduate School of Science, Osaka City University, Sugimoto, Osaka 558-8585, Japan, Fax: +81-6-6605-3153,
E-mail: ohfune@sci.osaka-cu.ac.jp 相似文献
3.
Summary. Alterations in hepatic metabolism of S-amino acids were monitored over one week in male rats treated with a single dose of
ethanol (3 g/kg, ip). Methionine and S-adenosylhomocysteine concentrations were increased rapidly, but S-adenosylmethionine,
cysteine, and glutathione (GSH) decreased following ethanol administration. Activities of methionine adenosyltransferase,
cystathionine γ-lyase and cystathionine β-synthase were all inhibited. γ-Glutamylcysteine synthetase activity was increased from t = 8 hr, but GSH level did not return to control for 24 hr. Hepatic
hypotaurine and taurine levels were elevated immediately, but reduced below control in 18 hr. Changes in serum and urinary
taurine levels were consistent with results observed in liver. Cysteine dioxygenase activity was increased rapidly, but declined
from t = 24 hr. The results show that a single dose of ethanol induces profound changes in hepatic S-amino acid metabolism,
some of which persist for several days. Ethanol not only inhibits the cysteine synthesis but suppresses the cysteine availability
further by enhancing its irreversible catabolism to taurine, which would play a significant role in the depletion of hepatic
GSH.
Received April 26, 2002 Accepted June 12, 2002 Published online October 14, 2002
Authors' address: Young C. Kim, Ph.D., Professor of Toxicology, College of Pharmacy, Seoul National University, San 56-1 Shinrim-Dong, Kwanak-Ku,
Seoul, Korea, Fax: +82-2-872-1795, E-mail: youckim@snu.ac.kr
Abbreviations: CβS, cystathionine β-synthase; CDC, cysteine sulfinate decarboxylase; CDO, cysteine dioxygenase; CγL, cystathionine γ-lyase; GCS, γ-Glutamylcysteine synthetase; GSH, glutathione; MAT, methionine adenosyltransferase; SAH, S-adenosylhomocysteine; SAM, S-adenosylmethionine. 相似文献
4.
Della Corte L Crichton RR Duburs G Nolan K Tipton KF Tirzitis G Ward RJ 《Amino acids》2002,23(4):367-379
Summary. Despite the multitude of evidence for the beneficial effects of taurine supplementation in a variety of disease, the underlying
modifying action of taurine with respect to either molecular or biochemical mechanisms is almost totally unknown. We have
assessed the development of taurine analogues, particularly where there has been substitution at the suphonate or amine group.
Such substitutions allow the investigator to probe the relationship between structure and function of the taurine molecule.
In addition such studies should help to ascertain taurine's point of interaction with the effector molecule. These results
will prepare the way for the development of the second generation of taurine analogues.
Received January 2, 2002 Accepted January 28, 2002 Published online August 30, 2002
Acknowledgements This research has been funded by the COST Chemistry programmes COST D8 “Chemistry of Metals in Medicine” and D-13 “New Molecules
for Human Health Care”. All of the authors are members of the Working Group D13/0011/00 “Investigation of mechanisms underlying
the pharmacological actions of taurine upon cell apoptosis and calcium homeostasis”.
Authors' address: Dr. R.J. Ward, Unite de Biochimie, Catholic Universite de Louvain, Place Louis Pasteur 1, B-1348 Louvain-la-Neuve, Belgium,
E-mail: ward@bioc.ucl.ac.be 相似文献
5.
Summary. The effect of taurine (Tau) and taurine chloramine (Tau-Cl) on the production of TNF-α, IL-1β, and IL-6 by peripheral blood mononuclear cells of healthy volunteers was examined. Cells were stimulated with bacterial
lipopolysaccharide (LPS) in the presence of either Tau or Tau-Cl. After 24 h culture the cytokine concentrations were measured
in both culture supernatants (secreted) and cell lysates (cell-associated) using ELISA. In LPS-stimulated cells Tau-Cl inhibited
both the secreted and cell-associated IL-1β and IL-6, while exerted dual effect on TNF-α production: raising it slightly at low and reducing at higher concentration. By contrast, Tau had no significant effect on
the cytokine production. These results indicate that Tau-Cl modulates synthesis of pro-inflammatory cytokines, and therefore
it may play a role in the initiation and propagation of immune response.
Received November 29, 2001 Accepted January 18, 2002 Published online August 30, 2002
Acknowledgments This research was supported by grants from the State Committee for Scientific Research of Poland (No 4 P05B 01018) and the
Institute of Rheumatology (No I/14). The Institute of Rheumatology is supported by a core grant from the State Committee for
Scientific Research of Poland.
Authors' address: Ewa Kontny, Ph.D., Department of Pathophysiology and Immunology, Institute of Rheumatology, Spartanska 1, 02-637 Warsaw,
Poland, E-mail: zpatiir@warman.com.pl
Abbreviations: Tau, taurine; Tau-Cl, taurine chloramine; LPS, lipopolysaccharide; TNF-α, tumor necrosis factor-α; IL-1β, interleukin 1β; IL-6, interleukin 6; PBMC, peripheral blood mononuclear cells 相似文献
6.
Effect of ischemia,calcium depletion and repletion,acidosis and hypoxia on cellular taurine content 总被引:2,自引:0,他引:2
Summary. Occlusion of the left main coronary artery led to a time-dependent release of taurine from the heart. Upon reperfusion, there
was a second phase of taurine release, which exceeded the amount of taurine that exited the heart during the 45 min ischemic
insult. To obtain information on the mechanism underlying the release of taurine, three variables were examined, acidosis,
hypoxia and calcium overload. It was found that large amounts of taurine also leave the cell during the calcium paradox, a
condition induced by perfusing the heart with calcium containing buffer following a period of calcium free perfusion. However,
little taurine effluxes the hearts exposed to buffer whose pH was lowered to 6.6. Isolated neonatal cardiomyocytes subjected
to chemical hypoxia also lost large amounts of taurine. However, the amount of taurine leaving the cells appeared to be correlated
with the intracellular sodium concentration, [Na+]i. The data suggest that taurine efflux is regulated by [Na+]i and cellular osmolality, but not by cellular pH.
Received November 15, 2001 Accepted January 15, 2002 Published online October 3, 2002
Acknowledgements This study was supported with a grant from the Taisho Pharmaceutical Company.
Authors' address: Dr. Stephen W. Schaffer, Department of Pharmacology, University of South Alabama, School of Medicine, Mobile, Alabama, U.S.A.,
E-mail: sschaffe@jaguarl.usouthal.edu 相似文献
7.
Chronic taurine supplementation ameliorates oxidative stress and Na+ K+ ATPase impairment in the retina of diabetic rats 总被引:5,自引:0,他引:5
Di Leo MA Santini SA Cercone S Lepore D Gentiloni Silveri N Caputo S Greco AV Giardina B Franconi F Ghirlanda G 《Amino acids》2002,23(4):401-406
Summary. This study evaluates the effect of 4 months supplementation with 2% and 5% taurine (w/w) on the retina of diabetic rats.
In non-diabetic rats, taurine does not modify glycemia, body weight, retinal conjugated dienes (CD), lipid hydroperoxide (LP),
and Na+K+ATPase activity. In diabetic rat, at 2, 4, 8, 16 weeks following the onset of diabetes, retinal CD and LP are significantly
and progressively increased, while pump activity is gradually and significantly reduced. In taurine supplemented diabetic
rats, glycemia is not affected but lipid peroxidation is significantly decreased. Finally, taurine preserves ATPase activity
being 5% more effective than 2% taurine. We conclude that taurine supplementation ameliorates biochemical retinal abnormalities
caused by diabetes, thereby suggesting that taurine may have a role in the prevention of retinal changes in diabetes.
Received November 26, 2001 Accepted January 10, 2002 Published online October 3, 2002
Authors' address: Prof. Flavia Franconi, Department of Pharmacology, University of Sassari, Via Muroni 23a, I-07100 Sassari, Italy, Fax: 39-79228715,
E-mail: franconi@ssmain.uniss.it 相似文献
8.
Dietary taurine enhances cholesterol degradation and reduces serum and liver cholesterol concentrations in rats fed a high-cholesterol diet 总被引:1,自引:0,他引:1
Summary. The effect of taurine on hypercholesterolemia induced by feeding a high-cholesterol (HC) diet (10 g/kg) to rats was examined.
When taurine was supplemented to HC for 2 wk, serum total cholesterol significantly decreased and serum HDL-cholesterol increased
compared with the HC diet group. In the hypercholesterolemic rats fed the HC diet, the excretion of fecal bile acids and hepatic
cholesterol 7α-hydroxylase (CYP7A1) activity and its mRNA level increased significantly, and the supplementation of taurine further enhanced
these indexes, indicating an increase in cholesterol degradation. Agarose gel electrophoresis revealed that, in hypercholesterolemic
rats fed the HC diet, the serum level of the heavier VLDL increased significantly, but taurine repressed this increase and
normalized this pattern. Significant correlations were observed between the time-dependent increase of CYP7A1 gene expression
and the decrease of blood cholesterol concentration in rats fed the HC diet supplemented with taurine. These results suggest
that the hypocholesterolemic effects of taurine observed in the hypocholesterolemic rats fed the HC diet were mainly due to
the enhancement of cholesterol degradation and the excretion of bile acid.
Received December 4, 2001 Accepted January 2, 2002 Published online September 10, 2002
Acknowledgment This work was supported by a grant of Taisho Pharmaceutical Co., Ltd (Japan). We thank J. I. Gordon for their generous gifts
of cDNAs.
Authors' address: Dr. Hidehiko Yokogoshi, School of Food and Nutritional Sciences, The University of Shizuoka, Shizuoka 4228526, Japan, E-mail:
yokogosi@u-shizuoka-ken.ac.jp 相似文献
9.
Kontny E Wojtecka-ŁUkasik E Rell-Bakalarska K Dziewczopolski W Maśliński W Maślinski S 《Amino acids》2002,23(4):415-418
Summary. Taurine (Tau), a dominant free amino acid present in neutrophil cytoplasm, serves as a scavenger for hypochlorous acid (HOCl)
released during these cells activation. The resulting taurine chloramine (Tau-Cl) exerts potent anti-inflammatory properties.
In the present study we tested the hypothesis that the formation of Tau-Cl is impaired in neutrophils isolated from rheumatoid
arthritis (RA) patients. The inhibition of zymosan-triggered chemiluminescence in the presence of exogenous Tau was used for
indirect measurement of Tau-Cl generation. The chemiluminescence of neutrophils isolated from peripheral blood (PB) of healthy
volunteers and RA patients was inhibited by Tau with similar potency. By contrast, synovial fluid (SF) neutrophils of these
patients were significantly less sensitive for Tau-mediated inhibition. Therefore, our data indicate impaired generation of
Tau-Cl in neutrophils isolated from SF of RA patients.
Received November 29, 2001 Accepted January 9, 2002 Published online August 30, 2002
Acknowledgements This work was supported by grants from the State Committee for Scientific Research of Poland (No. P05A 104 19) and the Institute
of Rheumatology. The Institute of Rheumatology is supported by a core grant from the State Committee for Scientific Research
of Poland.
Authors' address: Ewa Kontny, Ph.D, Department of Pathophysiology and Immunology, Institute of Rheumatology, Spartanska 1, 02-637 Warsaw, Poland,
E-mail: zpatiir@warman.com.pl
Abbreviations: Tau, taurine; Tau-Cl, taurine chloramine; PB, peripheral blood; SF, synovial fluid; RA, rheumatoid arthritis 相似文献
10.
Summary. Oral taurine treatment has been studied extensively as a hypotensive agent. Several rat models of hypertension have been
used to prove that dietary taurine supplementation can alleviate high blood pressure, among other cardiovascular problems.
Experimental models mentioned in this review are the spontaneously hypertensive rat, the DOCA-salt rat, the Dahl-S rat, the
renovascular hypertensive rat, the hyperinsulinemic rat and the ethanol-treated rat. The beneficial effects of taurine were
also demonstrated in studies involving human subjects suffering essential hypertension. Taurine supplementation of 6 g/day
for as little as 7 days resulted in measurable decreases in blood pressure in these patients. In both rat and human studies,
the effects of taurine appeared to be dependent on the modulation of an overactive sympathetic system. However, taurine has
positive effects on other types of cardiovascular problems and thus may act through more than one mechanism.
Received January 8, 2002 Accepted January 18, 2002 Published online August 20, 2002
Acknowledgement The Taisho Pharmaceutical Co. of Tokyo, Japan, is thanked for their financial support to the senior author.
Authors' address: Dr. John B. Lombardini, Department of Pharmacology, Texas Tech University Health Sciences Center, Lubbock, U.S.A., E-mail:
jbarry. lombardini@ttmc.ttuhsc.edu 相似文献
11.
Summary. Sulfate and taurine are major end products of sulfur-containing amino acid metabolism in mammals including humans, and they
are excreted in urine. Average excretions (μmol/mg of creatinine) in the morning urine of 58 female college students were: total (free plus ester) sulfate (a), 12.53
± 3.85; free sulfate, 11.57 ± 3.69; taurine, 0.78 ± 0.53. Ratio of total sulfate and taurine was 10 : 0.6. Regression lines
obtained by plotting total sulfate, free sulfate, or total sulfate plus taurine against urea have shown that the former excretions
are significantly correlated with urea excretion. Excretion of total sulfate at zero point of urea excretion (b) was 5.30,
which corresponded to 42.3% of average excretion (12.53) and was assumed to be derived from dietary sulfate. The difference
7.23 (a − b) seemed to be derived from sulfur-containing amino acids. It was pointed out that the difference of average sulfate
excretion and sulfate excretion at zero urea excretion, namely a − b, was appropriate for the metabolic index of sulfur-containing
amino acids of the group examined. As free sulfate constituted 92.3% of total sulfate, excretion of ester sulfate was at a
constant level, and that of taurine was not significantly correlated with urea excretion, the value of free sulfate corresponding
to the value a − b of total sulfate mentioned above seemed to be a reliable and convenient index in the assessment of sulfur-containing
amino acid metabolism.
Received December 3, 2001 Accepted January 2, 2002 Published online August 30, 2002
Authors' address: Dr. Toshihiko Ubuka, Department of Clinical Nutrition, Kawasaki University of Medical Welfare, Kurashiki Okayama, 701-0193
Japan, E-mail: ubukatos@mw.kawasaki-m.ac.jp 相似文献
12.
Summary. This study investigates the relationship between changes in plasma sodium and changes in amino acid levels in a patient with
post-traumatic sepsis and prolonged critical illness. Ninety-two consecutive measurements were performed at regular intervals
over a period of many weeks; these consisted in the determination of full amino-acidograms, plasma sodium and complementary
variables. A unique, highly significant inverse correlation between taurine and plasma sodium was found (r2 = 0.48, p < 0.001). All other amino acids were unrelated, or much more weakly related, to sodium. Taurine was also strongly
and directly related to phosphoethanolamine, glutamate and aspartate. Changes in sodium and in levels of these amino acids
explained up to 86% of the variability of taurine. Besides, levels of these amino acids maintained a high degree of co-variation,
remaining reciprocally related one to each other, directly, with r2 ranging between 0.33 and 0.59 (p < 0.001 for all). There were similar findings for β-alanine, which however was measured inconsistently. These data provide gross clinical evidence of a specific link binding
plasma sodium and taurine levels, and may be consistent with occurrence of opposite and interdependent shifts of sodium and
taurine between intravascular and extravascular space, to maintain osmoregulation. Co-variation of taurine with the other
amino acids may be related to the same phenomenon, and/or to similarities in transport systems and chemical structure, or
true metabolic interactions.
Received April 16, 2002 Accepted June 19, 2002 Published online November 14, 2002
RID="*"
ID="*" Presented at the 7th International Congress on Amino Acids and Proteins, Vienna (Austria), August 6–10, 2001.
Acknowledgements The authors acknowledge the kind assistance of Mr. Maurizio Cianfanelli, from the Catholic University School of Medicine,
Rome, Italy.
Authors' address: Dr. Carlo Chiarla, Via Augusto Tebaldi, 19, I-00168 Roma, Italy, E-mail: carlo.chiarla@rm.unicatt.it 相似文献
13.
Summary. 2H-Pyran-2-ones 1 were transformed with various hydrazines into (E)- or (Z)-α,β-didehydro-α-amino acid (DDAA) derivatives 4 (and 7) containing a highly substituted pyrazolyl moiety attached at the β-position. With heterocyclic hydrazines, the products 4 were accompanied also by decarboxylated enamines E-6. In order to separate (E/Z)-mixtures of acids, they were transformed to the corresponding methyl esters 9 and 10 by the application of diazomethane. Catalytic hydrogenation under high pressures with Pd/C as a catalyst resulted in the formation
of racemic alanine derivatives 11.
Received January 29, 2002 Accepted May 27, 2002 Published online December 18, 2002
RID="*"
ID="*" Dedicated with deep respect to Professor Waldemar Adam on the occasion of his 65th birthday.
Acknowledgements We thank the Ministry of Education, Science and Sport of the Republic of Slovenia for the financial support (P0-0503-103).
Dr. B. Kralj and Dr. D. Žigon (Center for Mass Spectroscopy, “Jožef Stefan” Institute, Ljubljana, Slovenia) are gratefully
acknowledged for the mass measurements.
Authors' address: Prof. Marijan Kočevar, Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana,
Slovenia, E-mail: marijan.kocevar@uni-lj.si 相似文献
14.
Summary. Asymmetric synthesis of all four stereoisomers of 6-methylpipecolic acids with high enantiomeric purity via iterative AD
reaction, starting from 1,6-heptadiene, has been described.
Received March 25, 2002 Accepted June 15, 2002 Published online January 30, 2003
Authors' address: Hiroki Takahata, Faculty of Pharmaceutical Sciences, Tohoku Pharmaceutical University, Sendai 981-8558, Japan, E-mail: takahata@tohoku-pharm.ac.jp
RID="*"
ID="*" The stereo-configurations of 8 and 9 in Fig. 3 and 12 in Fig. 4 show only major isomers.
RID="**"
ID="**" The absolute configurations of 11 and 14 相似文献
15.
Summary. Hepatocyte preparations highly enriched in cells from either the periportal or the perivenous zone of the liver acinus were
prepared using a digitonin/collagenase perfusion method. Five enzymes of cysteine metabolism were assayed in both periportal
and perivenous preparations. The ratios of periportal to perivenous activity were 0.76, 0.60, 0.81, 1.62, and 1.01 for cysteine
dioxygenase, cysteinesulfinate decarboxylase, γ-glutamylcysteine synthetase, cystathionase, and asparate (cysteinesulfinate) aminotransferase, respectively. Only cysteinesulfinate
decarboxylase activity was significantly different between periportal and perivenous cells. In incubations with 2 mmol/L [35S]cysteine, total cysteine catabolism ([35S]taurine plus [35S]sulfate) between periportal and perivenous cells was not different, which is consistent with the observation of similar
cysteine dioxygenase activity across the hepatic acinus. Consistent with the lower cysteinesulfinate decarboxylase activity
in periportal cells, 16% of the total catabolism of [35S]cysteine in periportal cells resulted in taurine synthesis compared to 28% in perivenous cells. A lower rate of [35S]glutathione synthesis was observed in periportal cells compared to perivenous cells, but γ-glutamylcysteine synthetase activity was not significantly different between perivenous and periportal cells. Cysteinesulfnate
decarboxylase can be added to the list of enzymes whose activities are markedly enriched in perivenous cells.
Received January 15, 2002 Accepted February 4, 2002 Published online September 4, 2002
Acknowledgements This work was supported by the National Research Initiative Competitive Grants Program/United States Department of Agriculture
Competitive Research Grant 02-37200-7583.
Authors' address: Dr. Martha H. Stipanuk, Division of Nutritional Sciences, 227 Savage Hall, Cornell University, Ithaca, NY 14853-6301, U.S.A.,
E-mail: mhs6@cornell.edu 相似文献
16.
Farriol M Venereo Y Rosselló J Gomez P Palao R Orta X Segovia-Silvestre T 《Amino acids》2002,23(4):441-445
Summary. This study determines the effects of taurine (Tau) on phagocytosis of polymorphonuclear neutrophils (PMN) isolated from normal
subjects (n = 41) and severely burned patients (n = 20). Phagocytosis was measured by nitroblue of tetrazolium (NBT) reduction
in samples with and without latex bead stimulation. Taurine was added at doses of 0.2, 0.4, 0.8 and 1.6 mM to stimulated samples.
In control cells there were statistically significant increases in phagocytosis after addition of Tau 0.8 mM and 1.6 mM to
as compared to samples without Tau addition (295 ± 23% and 330 ± 35% vs. 248 ± 18%; mean ± S.E.; p < 0.05). A statistically
significant increase in phagocytosis was observed in cells from the burned population after addition of Tau 1.6 mM (288 ±
38% vs. 198 ± 13%; mean ± S.E.; p < 0.05). No changes in phagocytosis were found in cells from a subgroup of burn patients
(n = 13) followed over 7, 15 and 21 days. These results indicate that taurine supplementation in vitro at doses of 0.8 to
1.6 mM improves the phagocytic capacity of neutrophils in healthy subjects and in patients with severe burn injury, mainly
when neutrophil function is unaltered.
Received December 17, 2001 Accepted January 17, 2002 Published online August 30, 2002
Authors' address: Dr. Mireia Farriol, Centre d'Investigacions Bioquímicas i Biología Molecular (CIBBIM), Hospital General Vall d'Hebron Passeig
Vall d'Hebron 119-129, E-08035 Barcelona, Spain, Fax: 34-93-2746831, E-mail: farriol@hg.vhebron.es 相似文献
17.
Summary. The 14-residue peptaibol antibiotic trichovirin I 4A of the structure Ac-Aib-L-Asn-L-Leu-Aib-L-Pro-L-Ala-L-Val-Aib-L-Pro-Aib-L-Leu-Aib-L-Pro-L-Leuol
(Aib = α-aminoisobutyric acid, Leuol = leucinol) was synthesized by stepwise conventional solution phase synthesis using the Z/OtBu(OMe) strategy and HOBt/EDC as coupling reagents. Intermediates were fully characterized and the identity of the synthetic
peptide with the component 4A of the natural, microheterogeneous peptide mixture was proven by electrospray mass spectrometry,
HPLC, and bioassay.
Received March 25, 2002 Accepted June 14, 2002 Published online December 18, 2002
RID="*"
ID="*" Dedicated to Prof. Dr. Günther Jung. Tübingen University, on the occasion of his 65th anniversary.
Authors' address: Prof. Dr. Hans Brückner, Interdisciplinary Research Center, Institute of Nutritional Science, Department of Food Sciences,
Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26, D-35392 Giessen, Germany, Fax: +49-641-99-39149, E-mail: hans.brueckner@ernaehrung.uni-giessen.de
Abbreviations: Amino acids are abbreviated according to three-letter-nomenclature; Aib, α-aminoisobutyric acid (2-methylalanine); Iva (isovaline, 2-ethylalanine); Leuol, L-leucinol [(S)-2-amino-4-methyl-1-pentanol]; AAA, amino acid analysis; EI-MS, electron impact mass spectrometry; ESI-MS, electrospray ionization
mass spectrometry; HPLC, high performance liquid chromatography; Z, benzyloxycarbonyl; Fmoc, 9-fluorenylmethyoxycarbonyl;
OtBu, tertiary butoxy (tert-butylester); OMe, methoxy (methyl ester); OBzl, benzyloxy (benzyl ester); TDM, N,N,N′,N′-tetramethyl-4,4′-diamino-diphenylmethane
(Arnold's base); for other abbreviations see Experimental. 相似文献
18.
We describe the effects of trehalose on spawn storage in a home freezer (average temperature, −16°C) where edible fungi usually
do not survive. When the mycelia of Lentinula edodes were stored in a freezer for 3 days, the survival rate of mycelia cultivated on 2% glucose medium was 30%, whereas those
on media containing 2% and 5% trehalose were 50% and 60%, respectively. Addition of trehalose to the culture was more effective
in Pleurotus ostreatus. These results suggest that trehalose played the role of a stress protectant against freezing, because the mycelia cultured
on a trehalose medium grew more rapidly and produced more fruiting bodies compared to those cultured on glucose.
Received: February 6, 2002 / Accepted: October 1, 2002
Acknowledgments This work was partially supported by a Grant in Aid for Scientific Research (c) (2) No. 12660156 from the Japan Society for
the Promotion of Science. We also gratefully acknowledge a grant from Hokuto Foundation for the Promotion of Biological Science.
Correspondence to:T. Terashita 相似文献
19.
González-Hernández JC Aguilera-Aguirre L Pérez-Vázquez V Ramírez J Clemente-Guerrero M Cortés-Rojo C Saavedra-Molina A 《Amino acids》2003,24(1-2):163-169
Summary. We studied the role of the D-amino acids (D-aa) D-serine, D-alanine, D-methionine, D-aspartate, D-tyrosine and D-arginine
on rat liver mitochondria. The stability of D-amino acids, mitochondrial swelling, transmembrane potential and oxygen consumption
were studied under oxidative stress conditions in rat liver mitochondria. In the presence of glutamate-malate all D-aas salts
increased mitochondrial swelling, while in the presence of succinate plus rotenone only D-ala, D-arg and D-ser, induced mitochondrial
swelling. The transmembrane potential (ΔΨ) was decreased in the presence of 1 μM Ca2+. The D-aas inhibited oxygen consumption in state 3. The D-aa studied exerted effects on mitochondria via an increase of free
radicals production.
Received January 15, 2002 Accepted April 14, 2002 Published online September 4, 2002
Acknowledgements The authors appreciated the partial economical support from Mexican grants of CONACYT (to A.S.-M. during its sabbatical)
and CIC-UMSNH (2.5) and critical readings from Rafael álvarez-González.
Authors' address: Alfredo Saavedra-Molina, Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo,
Edificio B-3. C.U., Morelia, Mich. 58030. México, Fax: 52-443-326-5788, E-mail: saavedra@zeus.umich.mx 相似文献
20.
Three aryl alcohol oxidases (AAOs; EC 1.1.3.7) I, II, and III from the culture filtrate of a strain of white-rot fungus Pleurotus ostreatus were purified by multistep chromatography. Each of the purified AAOs I, II, and III had the same molecular masses of 70 kDa
and 72 kDa on gel filtration chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively. Their
optimum temperature was 40°C, but their optimum pHs differed slightly. The N-terminal amino acid sequence of AAOs I, II, and
III was determined to be Ala-Asp-Lys-Asp-Tyr-Ile-Val-Val-Gly-Ala, which showed significant similarity to those of Pleurotus eryngii (80% identity) and Pleurotus ostreatus Florida (60% identity).
Received: May 30, 2002 / Accepted: July 10, 2002
Acknowledgment This work was supported in part by a Grant-in-Aid for the Encouragement of Young Scientists (no. 12760117) from the Ministry
of Education, Culture, Sports, Science and Technology, Japan.
Correspondence to:K. Okamoto 相似文献