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1.
《Bioscience, biotechnology, and biochemistry》2013,77(6):1598-1600
A maltose phosphorylase (EC 2.4.1.8; MPase) showed novel acceptor specificity and transferred the glucosyl moiety of maltose not only to sugars but also to various acceptors having alcoholic OH groups. Salicyl alcohol acted as acceptor for MPase from Enterococcus hirae, and the product, salicyl-O-α-D-glucopyranoside (α-SalGlc) was identified. The yield based on supplied salicyl alcohol was 86% (mol/mol). 相似文献
2.
Melanie Zaparty Dominik Esser Susanne Gertig Patrick Haferkamp Theresa Kouril Andrea Manica Trong K. Pham Julia Reimann Kerstin Schreiber Pawel Sierocinski Daniela Teichmann Marleen van Wolferen Mathias von Jan Patricia Wieloch Sonja V. Albers Arnold J. M. Driessen Hans-Peter Klenk Christa Schleper Dietmar Schomburg John van der Oost Phillip C. Wright Bettina Siebers 《Extremophiles : life under extreme conditions》2010,14(1):119-142
3.
The extremely thermophilic, obligately aerobic bacterium Sulfolobus solfataricus forms the tetrapyrrole precursor, -aminolevulinic acid (ALA), from glutamate by the tRNA-dependent five-carbon pathway. This pathway has been previously shown to occur in plants, algae, and most prokaryotes with the exception of the -group of proteobacteria (purple bacteria). An alternative mode of ALA formation by condensation of glycine and succinyl-CoA occurs in animals, yeasts, fungi, and the -proteobacteria. Sulfolobus and several other thermophilic, sulfur-dependent bacteria, have been variously placed within a subgroup of archaea (archaebacteria) named crenarchaeotes, or have been proposed to comprise a distinct prokaryotic group designated eocytes. On the basis of ribosomal structure and certain other criteria, eocytes have been proposed as predecessors of the nuclear-cytoplasmic descent line of eukaryotes. Because aplastidic eukaryotes differ from most prokaryotes in their mode of ALA formation, and in view of the proposed affiliation of eocytes to eukaryotes, it was of interest to determine how eocytes form ALA. Sulfolobus extracts were able to incorporate label from [1-14C]glutamate, but not from [2-14C]glycine, into ALA. Glutamate incorporation was abolished by preincubation of the extract with RNase. Sulfolobus extracts contained glutamate-1-semialdehyde aminotransferase activity, which is indicative of the five-carbon pathway. Growth of Sulfolobus was inhibited by gabaculine, a mechanism-based inhibitor of glutamate-1-semialdehyde aminotransferase, an enzyme of the five-carbon ALA biosynthetic pathway. These results indicate that Sulfolobus uses the five-carbon pathway for ALA formation.Abbreviations AHA
4-amino-5-hexynoic acid
- ALA
-aminolevulinic acid, Gabaculine, 3-amino-2,3-dihydrobenzoic acid
- GSA
glutamate 1-semialdehyde 相似文献
4.
Christa Schleper Richard Röder Tatjana Singer Wolfram Zillig 《Molecular genetics and genomics : MGG》1994,243(1):91-96
Three phenotypically stable mutants of the extremely thermophilic archaeon Sulfolobus solfataricus have been isolated by screening for β-galactosidase negative colonies on plates with X-Gal (5-bromo-4-chloro-3-indolyl-(3-d-galactopyranoside). From one of these mutants an insertion element, designated ISC1217, was isolated and characterized. Sequence analysis of ISC1217 and of the regions adjacent to the insertion site in the β-galactosidase gene revealed features typical of a transposable element: ISC1217 contained terminal inverted repeats and was flanked by a direct repeat of 6 bp. The 1147 by sequence contained an open reading frame encoding a putative protein of 354 amino acid residues and, overlapping this, two smaller open reading frames on the opposite strand. There were approximately 8 copies of the insertion element in the S. solfataricus genome. ISC1217 did not cross-hybridize with DNA of other Sulfolobus species. All three independently isolated β-galactosidase mutants of S. solfataricus arose by transposition of ISC1217 or a related element. 相似文献
5.
The specific activity of a recombinant β-glucosidase from Sulfolobus solfataricus for isoflavones was: daidzin > glycitin > genistin > malonyl genistin > malonyl daidzin > malonyl glycitin. The hydrolytic
activity of this enzyme for daidzin was highest at pH 5.5 and 90°C with a half-life of 18 h, a K
m of 0.5 mM, and a k
cat of 2532 s−1. The enzyme converted 1 mM daidzin to 1 mM daidzein after 1 h with a molar yield of 100% and a productivity of 1 mM h−1. Among β-glucosidases, that from S. solfataricus
β had the highest thermostability, k
cat, k
cat/K
m, conversion yield, and productivity in the hydrolysis of daidzin. 相似文献
6.
Birgit M?rtens Salim Manoharadas David Hasen?hrl Lukas Zeichen Udo Bl?si 《Nucleic acids research》2014,42(4):2505-2511
The translation initiation factor aIF2 of the crenarchaeon Sulfolobus solfataricus (Sso) recruits initiator tRNA to the ribosome and stabilizes mRNAs by binding via the γ-subunit to their 5′-triphosphate end. It has been hypothesized that the latter occurs predominantly during unfavorable growth conditions, and that aIF2 or aIF2-γ is released on relief of nutrient stress to enable in particular anew translation of leaderless mRNAs. As leaderless mRNAs are prevalent in Sso and aIF2-γ bound to the 5′-end of a leaderless RNA inhibited ribosome binding in vitro, we aimed at elucidating the mechanism underlying aIF2/aIF2-γ recycling from mRNAs. We have identified a protein termed Trf (translation recovery factor) that co-purified with trimeric aIF2 during outgrowth of cells from prolonged stationary phase. Subsequent in vitro studies revealed that Trf triggers the release of trimeric aIF2 from RNA, and that Trf directly interacts with the aIF2-γ subunit. The importance of Trf is further underscored by an impaired protein synthesis during outgrowth from stationary phase in a Sso trf deletion mutant. 相似文献
7.
Steviol is a diterpene isolated from the plant Stevia rebaudiana that has a potential role as an antihyperglycemic agent by stimulating insulin secretion from pancreatic beta cells and also has significant potential to diminish the renal clearance of anionic drugs and their metabolites. In this study, the lacS gene, which encodes a thermostable β-glycosidase (SSbgly) enzyme from the extremely thermoacidophillic archaeon Sulfolobus solfataricus, was cloned and expressed in E. coli Rossetta BL21(DE3)pLyS using lactose as an inducer. Through fermentation, SSbgly was expressed as a 61 kDa protein with activity of 24.3 U/mg and the OD600 of 23 was reached after 18 h induction with 10 mM lactose. Purified protein was obtained by Ni-Sepharose chromatography with a yield of 92.3%. SSbgly hydrolyzed steviol glycosides to produce steviol with a yield of 99.2%. The optimum conditions for steviol production were 50 U/ml SSbgly and 90 mg/ml Ste at 75 °C as determined by the response surface method. 相似文献
8.
Haferkamp P Kutschki S Treichel J Hemeda H Sewczyk K Hoffmann D Zaparty M Siebers B 《Biochemical Society transactions》2011,39(1):77-81
Within the SulfoSYS (Sulfolobus Systems Biology) project, the effect of temperature on a metabolic network is investigated at the systems level. Sulfolobus solfataricus utilizes an unusual branched ED (Entner-Doudoroff) pathway for sugar degradation that is promiscuous for glucose and galactose. In the course of metabolic pathway reconstruction, a glucose dehydrogenase isoenzyme (GDH-2, SSO3204) was identified. GDH-2 exhibits high similarity to the previously characterized GDH-1 (SSO3003, 61% amino acid identity), but possesses different enzymatic properties, particularly regarding substrate specificity and catalytic efficiency. In contrast with GDH-1, which exhibits broad substrate specificity for C5 and C6 sugars, GDH-2 is absolutely specific for glucose. The comparison of kinetic parameters suggests that GDH-2 might represent the major player in glucose catabolism via the branched ED pathway, whereas GDH-1 might have a dominant role in galactose degradation via the same pathway as well as in different sugar-degradation pathways. 相似文献
9.
Yohji Ezure 《Bioscience, biotechnology, and biochemistry》2013,77(7):2159-2165
A transglycosylation reaction with moranoline (1-deoxynojirimycin) was carried out with α-cyclodextrin as the glucose donor and Bacillus macerans amylase as cyclodextrin glycosyltransferase [EC 2.4.1.19]. The resultant transglycosylation products were hydrolyzed by glucoamylase [EC 3.2.1.3] from Rhizopus niveus. The hydrolyzate (the transglycosylation product of the lowest molecular weight) was isolated and the structure was found by physico-chemical methods to be 4-O-α-d-glucopyranosyl-moranoline. 相似文献
10.
Ginsenoside compound K (C-K) is attracting a lot of interest because of its biological and pharmaceutical activities, including hepatoprotective, antitumor, anti-wrinkling, and anti-skin aging activities. C-K has been used as the principal ingredient in skin care products. For the effective application of ginseng extracts to the manufacture of cosmetics, the PPD-type ginsenosides in ginseng extracts should be converted to C-K by enzymatic conversion. For increased yield of C-K from the protopanaxadiol (PPD)-type ginsenosides in red-ginseng extract (RGE), the α-l-arabinofuranoside-hydrolyzing α-l-arabinofuranosidase from Caldicellulosiruptor saccharolyticus (CS-abf) was used along with the β-d-glucopyranoside/α-l-arabinopyranoside-hydrolyzing β-glycosidase from Sulfolobus solfataricus (SS-bgly) because SS-bgly showed very low hydrolytic activity on the α-l-arabinofuranoside linkage in ginsenosides. The optimal reaction conditions for C-K production were as follows: pH 6.0, 80°C, 2 U/mL SS-bgly, 3 U/mL CS-abf, and 7.5 g/L PPD-type ginsenosides in RGE. Under these optimized conditions, SS-bgly supplemented with CS-abf produced 4.2 g/L C-K from 7.5 g/L PPD-type ginsenosides in 12 h without other ginsenosides, with a molar yield of 100% and a productivity of 348 mg/L/h. To the best of our knowledge, this is the highest concentration and productivity of C-K from ginseng extract ever published in literature. 相似文献
11.
Beatrice Cobucci-Ponzano Vincenzo Aurilia Gennaro Riccio Bernard Henrissat Pedro M. Coutinho Andrea Strazzulli Anna Padula Maria Michela Corsaro Giuseppina Pieretti Gabriella Pocsfalvi Immacolata Fiume Raffaele Cannio Mosè Rossi Marco Moracci 《The Journal of biological chemistry》2010,285(27):20691-20703
Carbohydrate active enzymes (CAZymes) are a large class of enzymes, which build and breakdown the complex carbohydrates of the cell. On the basis of their amino acid sequences they are classified in families and clans that show conserved catalytic mechanism, structure, and active site residues, but may vary in substrate specificity. We report here the identification and the detailed molecular characterization of a novel glycoside hydrolase encoded from the gene sso1353 of the hyperthermophilic archaeon Sulfolobus solfataricus. This enzyme hydrolyzes aryl β-gluco- and β-xylosides and the observation of transxylosylation reactions products demonstrates that SSO1353 operates via a retaining reaction mechanism. The catalytic nucleophile (Glu-335) was identified through trapping of the 2-deoxy-2-fluoroglucosyl enzyme intermediate and subsequent peptide mapping, while the general acid/base was identified as Asp-462 through detailed mechanistic analysis of a mutant at that position, including azide rescue experiments. SSO1353 has detectable homologs of unknown specificity among Archaea, Bacteria, and Eukarya and shows distant similarity to the non-lysosomal bile acid β-glucosidase GBA2 also known as glucocerebrosidase. On the basis of our findings we propose that SSO1353 and its homologs are classified in a new CAZy family, named GH116, which so far includes β-glucosidases (EC 3.2.1.21), β-xylosidases (EC 3.2.1.37), and glucocerebrosidases (EC 3.2.1.45) as known enzyme activities. 相似文献
12.
Contursi P Jensen S Aucelli T Rossi M Bartolucci S She Q 《Extremophiles : life under extreme conditions》2006,10(6):615-627
The Sulfolobus spindle virus, SSV2, encodes a tyrosine integrase which furthers provirus formation in host chromosomes. Consistently with the prediction made during sequence analysis, integration was found to occur in the downstream half of the tRNAGly (CCC) gene. In this paper we report the findings of a comparative study of SSV2 physiology in the natural host, Sulfolobus islandicus REY15/4, versus the foreign host, Sulfolobus solfataricus, and provide evidence of differently regulated SSV2 life cycles in the two hosts. In fact, whereas a significant induction of SSV2 replication takes place during the growth of the natural host REY15/4, the cellular content of SSV2 DNA remains fairly low throughout the incubation of the foreign host. The accumulation of episomal DNA in the former case cannot be traced to decreased packaging activity because of a simultaneous increase in the virus titre in the medium. In addition, the interaction between SSV2 and its natural host is characterized by the concurrence of host growth inhibition and the induction of viral DNA replication. When this virus–host interaction was investigated using S. islandicus REY15A, a strain which is closely related to the natural host, it was found that the SSV2 replication process was induced in the same way as in the natural host REY15/4. 相似文献
13.
NM Martucci A Lamberti L Vitagliano P Cantiello I Ruggiero P Arcari M Masullo 《Extremophiles : life under extreme conditions》2012,16(5):743-749
Guanosine tetra-phosphate (ppGpp), also known as "magic spot I", is a key molecule in the stringent control of most eubacteria and some eukarya. Here, we show that ppGpp affects the functional and molecular properties of the archaeal elongation factor 1α from Sulfolobus solfataricus (SsEF-1α). Indeed, ppGpp inhibited archaeal protein synthesis in vitro, even though the concentration required to get inhibition was higher than that required for the eubacterial and eukaryal systems. Regarding the partial reactions catalysed by SsEF-1α the effect produced by ppGpp on the affinity for aa-tRNA was lower than that measured in the presence of GTP but higher than that for GDP. Magic spot I was also able to bind SsEF-1α with an intermediate affinity in comparison to that displayed by GDP and GTP. Furthermore, ppGpp inhibited the intrinsic GTPase of SsEF-1α with a competitive behaviour. Finally, the binding of ppGpp to SsEF-1α rendered the elongation factor more resistant to heat treatment and the analysis of the molecular model of the complex between SsEF-1α and ppGpp suggests that this stabilisation arises from the charge optimisation on the surface of the protein. 相似文献
14.
Seiya Chiba Tokuji Shimomura Keiko Hatakeyama 《Bioscience, biotechnology, and biochemistry》2013,77(3):591-596
The transglucosylation reaction of buckwheat α-glucosidase was examined under the coexistence of 2-deoxy-d-glucose and maltose. As the transglucosylation products, two kinds of new disaccharide were chromatographically isolated in a crystalline form (hemihydrate). It was confirmed that these disaccharides were 3-O-α-d-glucopyranosyl-2-deoxy-d-glucose ([α]d + 132°, mp 130 ~ 132°C, mp of ±-heptaacetate 151 ~ 152°C) and 4-O-±-d-glucopyranosyl-2-deoxy-d-glucose ([±]d + 136°, mp 168 ~ 170°C), respectively. The principal product formed in the enzyme reaction was 3-O-±-d-glucopyranosyl-2-deoxy-d-glucose. 相似文献
15.
《Bioscience, biotechnology, and biochemistry》2013,77(8):1258-1261
The transglycosylation reaction was done with a β-galactanase from Penicillium citrinum. The regioselectivity in the transglycosylation reaction was studied using soy bean arabinogalactan as a donor and mono- or disaccharide derivatives containing β-galactosyl residue as acceptors. We also synthesized oligosaccharides containing Galβ1→4Gal sequence such as Galβ1→4Galβ1→4Glc, Galβ1→4Galβ1→3GlcNAc, Galβ1→4Galβ1→4GlcNAc, Galβ1→4Galβ1→6GlcNAc, and Galβ1→4Galβ1→3GalNAc for use in the total synthesis of complex sugar chains. 相似文献
16.
Michael Riis Hansen Kristine Steen Jensen Mads Skytte Rasmussen Stig Christoffersen Anders Kadziola Kaj Frank Jensen 《Extremophiles : life under extreme conditions》2014,18(1):179-187
Two open reading frames in the genome of Sulfolobus solfataricus (SSO2341 and SSO2424) were cloned and expressed in E. coli. The protein products were purified and their enzymatic activity characterized. Although SSO2341 was annotated as a gene (gpT-1) encoding a 6-oxopurine phosphoribosyltransferase (PRTase), the protein product turned out to be a PRTase highly specific for adenine and we suggest that the reading frame should be renamed apT. The other reading frame SSO2424 (gpT-2) proved to be a true 6-oxopurine PRTase active with hypoxanthine, xanthine and guanine as substrates, and we suggest that the gene should be renamed gpT. Both enzymes exhibited unusual profiles of activity versus pH. The adenine PRTase showed the highest activity at pH 7.5–8.5, but had a distinct peak of activity also at pH 4.5. The 6-oxo PRTase showed maximal activity with hypoxanthine and guanine around pH 4.5, while maximal activity with xanthine was observed at pH 7.5. We discuss likely reasons why SSO2341 in S. solfataricus and similar open reading frames in other Crenarchaeota could not be identified as genes encoding APRTase. 相似文献
17.
Giuseppe Perugino Pierpaolo Falcicchio Maria Michela Corsaro Ikuo Matsui Michelangelo Parrilli Mose’ Rossi 《Biocatalysis and Biotransformation》2013,31(1-2):23-29
The β-glycosidase from the hyperthermophilic Archaeon Pyrococcus horikoshii (Phoβ-gly) is a monomeric enzyme with wide substrate specificity belonging to family 1 of glycoside hydrolases classification. Inspection of the three-dimensional structure of the enzyme, recently resolved, showed that Phoβ-gly is membrane bound and that the residues putatively involved in the catalytic activity are Glu155 and Glu324 working as the general acid/base and the nucleophile of the reaction, respectively. We show here that mutation of the latter completely eliminated the activity of the enzyme and that it could be reactivated in the presence of sodium formate. Analysis of the products obtained in the presence of sodium formate buffer pH 4.0 at 75°C showed that the Glu324Gly mutant acts as a hyperthermophilic glycosynthase. 相似文献
18.
Reza Fathi Kenneth J. Nawoschik Melissa Zavoda Alan F. Cook 《Nucleosides, nucleotides & nucleic acids》2013,32(10-11):1907-1920
Abstract A wide range of 2′,5′-dideoxy-nucleosides, including 6- substituted purine, pyrazolo[3,4-d]pyrimidine and 1-deazapurine derivatives, has been enzymatically prepared using purine nucleoside phosphorylase. Specificity towards cleavage by bacterial versus mammalian purine nucleoside phosphorylase was evaluated. 相似文献
19.
Previously, we reported from the Sulfolobus solfataricus open reading frame (ORF) SSO2517 the cloning, overexpression and characterization of an esterase belonging to the hormone-sensitive lipase (HSL) family and apparently having a deletion at the N-terminus, which we named SSoNDelta. Searching the recently reported Sulfolobus acidocaldarius genome by sequence alignment, using SSO2517 as a query, allowed identity of a putative esterase (ORF SAC1105) sharing high sequence similarity (82%) with SSO2517. This esterase displays an N-terminus and total length similar to other known esterases of the HSL family. Analysis of the upstream DNA sequence of SS02517 revealed the possibility of expressing a longer version of the protein with an extended N-terminus; however, no clear translation signal consistent with a longer protein version was detected. This new version of SSO2517 was cloned, over-expressed, purified and characterized. The resulting protein, named SSoNDeltalong, was 15-fold more active with the substrate p-nitrophenyl hexanoate than SSoNDelta. Furthermore, SSoNDeltalong and SSoNDelta displayed different substrate specificities for triacylglycerols. These results and the phylogenetic relationship between S. solfataricus and S. acidocaldarius suggest a common origin of SSO2517 and SAC1105 from an ancestral gene, followed by divergent evolution. Alternatively, a yet-to-be discovered mechanism of translation that directs the expression of SSoNDeltalong under specific metabolic conditions could be hypothesized. 相似文献
20.
A. I. Zinchenko V. N. Barai S. B. Bokut N. V. Dudchik E. I. Kvasyuk I. A. Mikhailopulo 《Biotechnology letters》1991,13(2):87-90
Summary The title compound was prepared by a two step enzymatic procedure consisting of DNA hydrolysis to the mixture of 2-deoxynucleosides followed by a transdeoxyribosilation of exogenous adenine. 相似文献