- Noncovalently Functionalized Commodity Polymers as Tailor-Made Additives for Stereoselective Crystallization
-
Stereoselective inhibition of the nucleation and crystal growth of one enantiomer aided by “tailor-made” polymeric additives is an efficient method to obtain enantiopure compounds. However, the conventional preparation of polymeric additives from chiral monomers are laborious and limited in structures, which impedes their rapid optimization and applicability. Herein, we report a “plug-and-play” strategy to facilitate synthesis by using commercially available achiral polymers as the platform to attach various chiral small molecules as the recognition side-chains through non-covalent interactions. A library of supramolecular polymers made up of two vinyl polymers and six small molecules were applied with seeds in the selective crystallization of seven racemates in different solvents. They showed good to excellent stereoselectivity in yielding crystals with high enantiomeric purities in conglomerates and racemic compound forming systems. This convenient, low-cost modular synthesis strategy of polymeric additives will allow for high-efficient, economical resolution of various racemates on different scales.
- Wan, Xinhua,Wang, Zhaoxu,Ye, Xichong,Zhang, Jie
-
supporting information
p. 20243 - 20248
(2021/08/09)
-
- Direct monitoring of biocatalytic deacetylation of amino acid substrates by1H NMR reveals fine details of substrate specificity
-
Amino acids are key synthetic building blocks that can be prepared in an enantiopure form by biocatalytic methods. We show that thel-selective ornithine deacetylase ArgE catalyses hydrolysis of a wide-range ofN-acyl-amino acid substrates. This activity was revealed by1H NMR spectroscopy that monitored the appearance of the well resolved signal of the acetate product. Furthermore, the assay was used to probe the subtle structural selectivity of the biocatalyst using a substrate that could adopt different rotameric conformations.
- De Cesare, Silvia,McKenna, Catherine A.,Mulholland, Nicholas,Murray, Lorna,Bella, Juraj,Campopiano, Dominic J.
-
supporting information
p. 4904 - 4909
(2021/06/16)
-
- A method of synthesizing L - asparagine (by machine translation)
-
The invention provides a method of synthesizing L - asparagine, the main technical means is to L - aspartic acid as the raw material, first to the reaction in the cauldron the pump enters methanol, then open the reaction kettle, input L - aspartic acid, cooling, subsequently drop adds the chlorination sulfoxide, generating L - aspartic acid methyl ester hydrochloride, then will be of the L - aspartic acid methyl ester hydrochloride into a reaction kettle, then to the reaction in the cauldron the pump enters the ammonia, to obtain the L - asparagine, the method generating L - aspartic acid methyl ester hydrochloride intermediate product, the intermediate product is stable structure, safe and non-toxic, for subsequent operation processing, reaction process only needs to have the participation of ammonia water, reactant complex, the small influence of the product, the method of the invention recovery of the methanol up to 99.5 - 99.9%, not only improving the intermediate the purity of the product, and also avoids the pollution of methanol, L - asparagine is finished effective content of 80 - 85%, moisture content is 15 - 18%, yield and moisture content are higher than the amount of the existing products, the method of the invention is suitable for industrial production. (by machine translation)
- -
-
Page/Page column 4-6
(2019/05/08)
-
- Self-Reporting Inhibitors: A Single Crystallization Process To Obtain Two Optically Pure Enantiomers
-
Collection of two optically pure enantiomers in a single crystallization process can significantly increase the chiral separation efficiency but this is difficult to realize. Now a self-reporting strategy is presented for visualizing the crystallization process by a dyed self-assembled inhibitor made from the copolymers with tri(ethylene glycol)-grafting polymethylsiloxane as the main chain and poly(N6-methacryloyl-l-lysine) as side chains. When applied with seeds together for the fractional crystallization of conglomerates, the inhibitors can label the formation of the secondary crystals and guide the complete separation process of two enantiomers with colorless crystals as the first product and red crystals as the second. This method leads to high optical purity of d/l-Asn?H2O (99.9 % ee for d-crystals and 99.5 % for l-crystals) in a single crystallization process. It requires a small amount of additives and shows excellent recyclability.
- Ye, Xichong,Cui, Jiaxi,Li, Bowen,Li, Na,Zhang, Jie,Wan, Xinhua
-
p. 8120 - 8124
(2018/06/29)
-
- β-Cyclodextrin Functionalized Nanoporous Graphene Oxides for Efficient Resolution of Asparagine Enantiomers
-
Efficient resolution of racemic mixture has long been an attractive but challenging subject since Pasteur separated tartrate enantiomers in 19th century. Graphene oxide (GO) could be flexibly functionalized by using a variety of chiral host molecules and therefore, was expected to show excellent enantioselective resolution performance. However, this combination with efficient enantioselective resolution capability has been scarcely demonstrated. Here, nanoporous graphene oxides were produced and then covalently functionalized by using a chiral host material-β-cyclodextrin (β-CD). This chiral GO displayed enantioselective affinity toward the l-enantiomers of amino acids. In particular, >99 % of l-asparagine (Asn) was captured in a racemic solution of Asn while the adsorption of d-enantiomer was not observed. This remarkable resolution performance was subsequently modelled by using an attach-pull-release dynamic method. We expect this preliminary concept could be expanded to other chiral host molecules and be employed to current membrane separation technologies and finally show practical use for many other racemates.
- Qie, Fengxiang,Guo, Jiahui,Tu, Bin,Zhao, Xing,Zhang, Yuchun,Yan, Yong
-
supporting information
p. 2812 - 2817
(2018/09/12)
-
- Colony-wise Analysis of a Theonella swinhoei Marine Sponge with a Yellow Interior Permitted the Isolation of Theonellamide i
-
There are several examples of marine organisms whose metabolic profiles differ among conspecifics inhabiting the same region. We have analyzed the metabolic profile of each colony of a Theonella swinhoei marine sponge with a yellow interior and noticed the patchy distribution of one metabolite. This compound was isolated and its structure was studied by a combination of spectrometric analyses and chemical degradation, showing it to be a congener in the theonellamide class of bicyclic peptides. Theonellamides had previously been isolated by us only from T. swinhoei with a white interior and not from those with a yellow interior.
- Fukuhara, Kazuya,Takada, Kentaro,Watanabe, Ryuichi,Suzuki, Toshiyuki,Okada, Shigeru,Matsunaga, Shigeki
-
p. 2595 - 2599
(2018/12/13)
-
- Preparation and purification method of amino acid compound
-
The invention relates to the field of industrial organic synthesis, in particular to a preparation and purification method of an amino acid compound. The method comprises the following steps that (1)alpha-amino nitrile compounds or hydantoin compounds or mixtures thereof are heated to react to obtain alpha-amino acid salt under the condition that volatile alkali and a suitable solvent exist; (2)after the alpha-amino acid salt obtained in step (1) is distilled, the alpha-amino acid salt is recrystallized in an organic solvent to obtain the alpha-amino acid compound. According to the method, reaction conditions are mild, materials can be recycled, and introduction of metal ions and use of ammonium carbonate salt are avoided, so that post-treatment is simple and no waste salt is generated.
- -
-
Paragraph 0060; 0061; 0062; 0063
(2018/06/21)
-
- Chromatographic Resolution of α-Amino Acids by (R)-(3,3'-Halogen Substituted-1,1'-binaphthyl)-20-crown-6 Stationary Phase in HPLC
-
Three new chiral stationary phases (CSPs) for high-performance liquid chromatography were prepared from R-(3,3'-halogen substituted-1,1'-binaphthyl)-20-crown-6 (halogen = Cl, Br and I). The experimental results showed that R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6 (CSP-1) possesses more prominent enantioselectivity than the two other halogen-substituted crown ether derivatives. All twenty-one α-amino acids have different degrees of separation on R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6-based CSP-1 at room temperature. The enantioselectivity of CSP-1 is also better than those of some commercial R-(1,1'-binaphthyl)-20-crown-6 derivatives. Both the separation factors (α) and the resolution (Rs) are better than those of commercial crown ether-based CSPs [CROWNPAK CR(+) from Daicel] under the same conditions for asparagine, threonine, proline, arginine, serine, histidine and valine, which cannot be separated by commercial CR(+). This study proves the commercial usefulness of the R-(3,3'-dibromo-1,1'-binaphthyl)-20-crown-6 chiral stationary phase.
- Wu, Peng,Wu, Yuping,Zhang, Junhui,Lu, Zhenyu,Zhang, Mei,Chen, Xuexian,Yuan, Liming
-
supporting information
p. 1037 - 1042
(2017/07/25)
-
- Degradation of complexons derived from succinic acid under UV radiation
-
The destruction of complexons derived from succinic acid under the action of UV radiation was studied. IR spectroscopy, thin-layer paper chromatography, and complexometric titration were used to determine the destruction products of these complexons. It was found that the complexons decompose under UV irradiation substantially more easily than ethylenediaminetetraacetic acid does, and the products of their decomposition can undergo a biological utilization under natural conditions. The data obtained in the study make it possible to choose, instead of ethylenediaminetetraacetic acid, ligands that will be nearly fully destructible in the light without deteriorating the ecology.
- Smirnova,Khizhnyak,Nikol’skii,Khalyapina, Ya. M.,Pakhomov
-
p. 507 - 511
(2017/08/02)
-
- Influence of the amino acid side chain on peptide bond hydrolysis catalyzed by a dimeric Zr(iv)-substituted Keggin type polyoxometalate
-
Peptide bond hydrolysis of 18 different dipeptides, divided into four groups depending on the nature of the amino acid side chain, by the dimeric Zr(iv)-substituted Keggin type polyoxometalate (POM) (Et2NH2)8[{α-PW11O39Zr-(μ-OH)(H2O)}2]·7H2O (1) was studied by means of kinetic experiments and 1H/13C NMR spectroscopy. The observed rate constants highly depend on the bulkiness and chemical nature of the X amino acid side chain. X-Ser and X-Thr dipeptides showed increased reactivity due to intramolecular nucleophilic attack of the hydroxyl group in the side chain on the amide carbon, resulting in a reactive ester intermediate. A similar effect in which the amino acid side chain acted as an internal nucleophile was observed for the hydrolysis of Gly-Asp. Interestingly, in the presence of 1 deamidation of Gly-Asn and Gly-Gln into Gly-Asp and Gly-Glu was observed. Dipeptides containing positively charged amino acid side chains were hydrolyzed at higher rates due to electrostatic interactions between the negatively charged POM surface and positive amino acid side chains.
- Ly, Hong Giang T.,Absillis, Gregory,Parac-Vogt, Tatjana N.
-
p. 976 - 984
(2016/02/19)
-
- Enantiospecific C-H Activation Using Ruthenium Nanocatalysts
-
The activation of C-H bonds has revolutionized modern synthetic chemistry. However, no general strategy for enantiospecific C-H activation has been developed to date. We herein report an enantiospecific C-H activation reaction followed by deuterium incorporation at stereogenic centers. Mechanistic studies suggest that the selectivity for the α-position of the directing heteroatom results from a four-membered dimetallacycle as the key intermediate. This work paves the way to novel molecular chemistry on nanoparticles.
- Taglang, Céline,Martínez-Prieto, Luis Miguel,Del Rosal, Iker,Maron, Laurent,Poteau, Romuald,Philippot, Karine,Chaudret, Bruno,Perato, Serge,Sam Lone, Ana?s,Puente, Céline,Dugave, Christophe,Rousseau, Bernard,Pieters, Grégory
-
supporting information
p. 10474 - 10477
(2015/09/02)
-
- Microseiramide from the freshwater cyanobacterium Microseira sp. UIC 10445
-
Abstract Microseiramide (1), a cyclic heptapeptide, was isolated from a sample of the freshwater cyanobacterium Microseira sp. UIC 10445 collected in a shallow lake in Northern Indiana. Taxonomic identification of UIC 10445 was performed by a combination of morphological and phylogenetic characterization. Phylogenetic analysis revealed that UIC 10445 was a member of the recently described genus Microseira, which is phylogenetically distinct from the morphologically similar genera, Moorea and Lyngbya. The planar structure of microseiramide (1) was determined by extensive 1D and 2D NMR experiments as well as HRESIMS analysis. The absolute configurations of amino acid residues were determined using acid hydrolysis followed by the advanced Marfey's analysis. Microseiramide (1) is the first cyclic peptide reported from a Microseira sp., and the structure of microseiramide (1) is distinct from the previously known metabolites from cyanobacteria of the genera Moorea and Lyngbya.
- Luo, Shangwen,Krunic, Aleksej,Chlipala, George E.,Orjala, Jimmy
-
-
- Chemical evolution of simple amino acids to asparagine under discharge onto the primitive hydrosphere: Simulation experiments using contact glow discharge
-
Asparagine is an important amino acid for abiotic polypeptide synthesis. In simulation experiments, it was obtained in 3.0% yield (based on the amount of consumed alanine) from alanine (100 mM) and formamide (200 mM) by contact glow discharge (Harada discharge) onto aqueous solutions. The present results suggest that asparagine could be abiotically synthesized from simple amino acids under possible primitive earth conditions.
- Munegumi, Toratane
-
p. 1208 - 1215
(2015/02/19)
-
- A mild removal of Fmoc group using sodium azide
-
A mild method for effectively removing the fluorenylmethoxycarbonyl (Fmoc) group using sodium azide was developed. Without base, sodium azide completely deprotected Nα-Fmoc-amino acids in hours. The solvent-dependent conditions were carefully studied and then optimized by screening different sodium azide amounts and reaction temperatures. A variety of Fmoc-protected amino acids containing residues masked with different protecting groups were efficiently and selectively deprotected by the optimized reaction. Finally, a biologically significant hexapeptide, angiotensin IV, was successfully synthesized by solid phase peptide synthesis using the developed sodium azide method for all Fmoc removals. The base-free condition provides a complement method for Fmoc deprotection in peptide chemistry and modern organic synthesis. Graphical Abstract: [Figure not available: see fulltext.]
- Chen, Chun-Chi,Rajagopal, Basker,Liu, Xuan Yu,Chen, Kuan Lin,Tyan, Yu-Chang,Lin, Fui,Lin, Po-Chiao
-
p. 367 - 374
(2014/03/21)
-
- SEPARATING AGENT AND MANUFACTURING METHOD THEREOF
-
An embodiment of the present invention is a separating agent wherein a group represented by a chemical formula of: or a group represented by a chemical formula of: is introduced on a surface thereof.
- -
-
Paragraph 0067; 0068; 0069; 0070; 0071; 0072; 0087; 0088
(2015/01/07)
-
- Facile synthesis of α-hydroxy carboxylic acids from the corresponding α-amino acids
-
An effective and improved procedure is developed for the synthesis of α-hydroxy carboxylic acids by treatment of the corresponding protonated α-amino acid with tert-butyl nitrite in 1,4-dioxane-water. The amino moiety must be protonated and located α to a carboxylic acid function in order to undergo initial diazotization and successive hydroxylation, since neither β-amino acids nor acid derivatives such as esters and amides undergo hydroxylations. The method is successfully applied for the synthesis of 18 proteinogenic amino acids.
- Stuhr-Hansen, Nicolai,Padrah, Shahrokh,Str?mgaard, Kristian
-
supporting information
p. 4149 - 4151
(2015/02/02)
-
- Cystomanamides: Structure and biosynthetic pathway of a family of glycosylated lipopeptides from myxobacteria
-
Cystomanamides A-D were isolated as novel natural product scaffolds from Cystobacter fuscus MCy9118, and their structures were established by spectroscopic techniques including 2D NMR, LC-SPE-NMR/-MS, and HR-MS. The cystomanamides contain β-hydroxy amino acids along with 3-amino-9-methyldecanoic acid that is N-glycosylated in cystomanamide C and D. The gene cluster for cystomanamide biosynthesis was identified by gene disruption as PKS/NRPS hybrid incorporating an iso-fatty acid as starter unit and including a reductive amination step at the interface of the PKS and NRPS modules.
- Etzbach, Lena,Plaza, Alberto,Garcia, Ronald,Baumann, Sascha,Mueller, Rolf
-
supporting information
p. 2414 - 2417
(2014/05/20)
-
- SEPARATING AGENT FOR CHROMATOGRAPHY
-
A separating agent for chromatography is provided that is useful for the separation of specific compounds, e.g., for the optical resolution of amino acids. This separating agent for chromatography provides a higher productivity and contains a crown ether-like cyclic structure and optically active binaphthyl. This separating agent for chromatography containing a crown ether-like cyclic structure and optically active binaphthyl is provided by introducing a substitution group for binding to carrier into a specific commercially available 1,1′-binaphthyl derivative that has substituents at the 2, 2′, 3, and 3′ positions, then introducing a crown ether-like cyclic structure, and subsequently chemically bonding the binaphthyl derivative to the carrier through the substitution group for binding to carrier.
- -
-
Paragraph 0074; 0075
(2013/08/15)
-
- Microbial enantioselective removal of the N-benzyloxycarbonyl amino protecting group
-
In order to deprotect N-carbobenzoxy-l-aminoacids (Cbz-AA) and related compounds, a series of microorganisms was selected from soil by enrichment cultures with Cbz-l-Glu as sole nitrogen source. A lyophilized whole-cell preparation of two Arthrobacter sp. strains grown on Cbz-Glu or Cbz-Gly exhibited a high cleavage activity. The conditions of hydrolysis have been optimized and a quantitative enantioselective deprotection of several Cbz-dl-amino acids was obtained, as well as the deprotection of N-carbamoylester derivatives of several synthetic amino compounds. The preparation of Cbz-d-allylglycine and l-allylglycine in high yield and high optical purity is described as an application of this method.
- Maurs, Michele,Acher, Francine,Azerad, Robert
-
-
- Cytotoxic cyclic depsipeptides from the Australian marine sponge Neamphius huxleyi
-
Three new cyclic depsipeptides, neamphamides B (2), C (3), and D (4), were isolated from the Australian sponge Neamphius huxleyi. The planar structural characterization of these molecules was elucidated using 2D NMR experiments and ESI-FTICR-MSn. Their configurations were determined by Marfey's method and J-based NMR analysis. These new metabolites inhibited the growth of human cell lines (A549, HeLa, LNCaP, PC3, and NFF) with IC50 values ranging from 88 to 370 nM. However, neamphamide D causes A549 cell proliferation at subcytotoxic doses and should be treated cautiously as a cytotoxic compound.
- Tran, Trong D.,Pham, Ngoc B.,Fechner, Gregory,Zencak, Dusan,Vu, Hoan T.,Hooper, John N.A.,Quinn, Ronald J.
-
p. 2200 - 2208
(2013/02/25)
-
- An efficient route to both enantiomers of allo-threonine by simultaneous amino acid racemase-catalyzed isomerization of threonine and crystallization
-
We present an efficient method for the production of D- and L-allo-threonine (allo-Thr) with very high purity by enzymatic isomerization of L- or D-threonine (Thr) and simultaneous crystallization. Isomerization of Thr to allo-Thr is catalyzed by a purified amino acid racemase (AArac12996) from Pseudomonas putida NBRC12996, which can easily be obtained from a recombinant E. coli strain by secretion into the medium and subsequent anion exchange chromatography. Crystallization of D- and L-allo-Thr was performed in a repetitive batch mode over a period of up to 55 days at 30 °C. Total amounts of 30.8 g D-allo-Thr and 32.4 g L-allo-Thr were obtained with a very good diastereomeric excess of deD-allo>99.2% and de L-allo>98.4%, respectively, and in good yields (D-allo-Thr: 83%, L-allo-Thr: 79%). The enzyme's remarkable high stability under process conditions resulted in enzyme specific yields of 2.56 g D-allo-Thr per mg AArac12996 and 1.62 g L-allo-Thr per mg AArac12996. In contrast to chemical multi-step syntheses of allo-Thr, our process consists of only one enzyme-catalyzed reaction step with simultaneous product crystallization. The process is performed under low energy consumption (30 °C, atmospheric pressure) in water and avoids the use and production of any toxic or harmful compounds. Recovery of the enantiomerically pure products is performed by simple filtration which reduces downstream processing significantly compared to chromatographic methods which are usually applied. Copyright
- Wuerges, Kerstin,MacKfeld, Ursula,Pohl, Martina,Luetz, Stephan,Wilhelm, Susanne,Wiechert, Wolfgang,Kubitzki, Tina
-
experimental part
p. 2431 - 2438
(2011/11/06)
-
- Structure, mechanism, and substrate profile for Sco3058: The closest bacterial homologue to human renal dipeptidase
-
Human renal dipeptidase, an enzyme associated with glutathione metabolism and the hydrolysis of β-lactams, is similar in sequence to a cluster of ~400 microbial proteins currently annotated as nonspecific dipeptidases within the amidohydrolase superfamily. The closest homologue to the human renal dipeptidase from a fully sequenced microbe is Sco3058 from Streptomyces coelicolor. Dipeptide substrates of Sco3058 were identified by screening a comprehensive series of L-Xaa-L-Xaa, L-Xaa-D-Xaa, and D-Xaa-L-Xaa dipeptide libraries. The substrate specificity profile shows that Sco3058 hydrolyzes a broad range of dipeptides with a marked preference for an L-amino acid at the N-terminus and a D-amino acid at the C-terminus. The best substrate identified was L-Arg-D-Asp (kcat/Km = 7.6 x 105 M -1 s-1). The three-dimensional structure of Sco3058 was determined in the absence and presence of the inhibitors citrate and a phosphinate mimic of L-Ala-D-Asp. The enzyme folds as a (β/α)8 barrel, and two zinc ions are bound in the active site. Site-directed mutagenesis was used to probe the importance of specific residues that have direct interactions with the substrate analogues in the active site (Asp-22, His-150, Arg-223, and Asp-320). The solvent viscosity and kinetic effects of D2O indicate that substrate binding is relatively sticky and that proton transfers do not occurr during the rate-limiting step. A bell-shaped pH-rate profile for kcat and kcat/Km indicated that one group needs to be deprotonated and a second group must be protonated for optimal turnover. Computational docking of high-energy intermediate forms of L/D-Ala-L/D-Ala to the three-dimensional structure of Sco3058 identified the structural determinants for the stereochemical preferences for substrate binding and turnover.
- Cummings, Jennifer A.,Nguyen, Tinh T.,Fedorov, Alexander A.,Kolb, Peter,Xu, Chengfu,Fedorov, Elena V.,Shoichet, Brian K.,Barondeau, David P.,Almo, Steven C.,Raushel, Frank M.
-
experimental part
p. 611 - 622
(2011/01/04)
-
- A conserved glutamate controls the commitment to acyl-adenylate formation in asparagine synthetase
-
Inhibitor docking studies have implicated a conserved glutamate residue (Glu-348) as a general base in the synthetase active site of the enzyme asparagine synthetase B from Escherichia coli (AS-B). We now report steady-state kinetic, isotope transfer, and positional isotope exchange experiments for a series of site-directed AS-B mutants in which Glu-348 is substituted by conservative amino acid replacements. We find that formation of the β-aspartyl-AMP intermediate, and therefore the eventual production of asparagine, is dependent on the presence of a carboxylate side chain at this position in the synthetase active site. In addition, Glu-348 may also play a role in mediating the conformational changes needed to (i) coordinate, albeit weakly, the glutaminase and synthetase activities of the enzyme and (ii) establish the structural integrity of the intramolecular tunnel along which ammonia is translocated. The importance of Glu-348 in mediating acyl-adenylate formation contrasts with the functional role of the cognate residues in β-lactam synthetase (BLS) and carbapenam synthetase (CPS) (Tyr-348 and Tyr-345, respectively), which both likely evolved from asparagine synthetase. Given the similarity of the chemistry catalyzed by AS-B, BLS, and CPS, our work highlights the difficulty of predicting the functional outcome of single site mutations on enzymes that catalyze almost identical chemical transformations.
- Meyer, Megan E.,Gutierrez, Jemy A.,Raushel, Frank M.,Richards, Nigel G. J.
-
experimental part
p. 9391 - 9401
(2011/11/28)
-
- Purification, characterization, molecular cloning, and expression of a new aminoacylase from streptomyces mobaraensis that can hydrolyze N-(Middle/Long)-chain-fatty-acyl-L-amino acids as well as N-Short-chain-acyl-L- amino acids
-
We report here on the purification, characterization, molecular cloning, and expression of a new aminoacylase, initially isolated from the supernatant of Streptomyces mobaraensis (Sm-AA). Purified wild-type Sm-AA was found to be a monomeric protein with a molecular mass of 55 kDa. The cloned gene of Sm-AA contained an ORF of 1,383 bp, encoding a polypeptide of 460 amino acids. A BLAST search revealed that Sm-AA belongs to the peptidase M20 family, with identities to a hypothetical protein from Streptomyces pristinaespiralis, a putative peptidase from Streptomyces avermitilis, peptidase M20 from Frankia sp., succinyl-diaminopimelate desuccinylase from Hemophilus influenzae, and aminoacylase-1 from porcine kidney at 89, 88, 67, 29, and 25% respectively. The Sm-AA gene was subcloned into an expression vector, pSH19, and was expressed in Streptomyces lividans TK24. The amount of the recombi- nant Sm-AA expressed in the S. lividans cells was approximately 42-fold higher than that of Sm-AA found in the supernatant of S. mobaraensis. Sm-AA showed high hydrolytic activity towards various N-acetyl-L-amino acids and N-(middle/long)-chain-fatty-acyl-L- amino acids, with a preference for the acyl derivatives of L-Met, L-Ala, L-Cys, etc. with an optimum pH and temperature for reaction of about 7.5 and 50 °C (at pH 7.5).
- Koreishi, Mayuko,Nakatani, Yasuyuki,Ooi, Manami,Imanaka, Hiroyuki,Imamura, Koreyoshi,Nakanishi, Kazuhiro
-
experimental part
p. 1940 - 1947
(2010/07/02)
-
- Synthesis of pyrimidines and triazines in ice: Implications for the prebiotic chemistry of nucleobases
-
Herein, we report the efficient synthesis of RNA bases and func-tionalized s-triazines from 0.1 M urea solutions in water after subjection to freeze-thaw cycles for three weeks. The icy solution was under a reductive, methane-based atmosphere, which was s
- Menor-Salvan, Cesar,Ruiz-Bermejo, Dra. Marta,Guzman, Marcelo I.,Osuna-Esteban, Susana,Veintemillas-Verdaguer, Sabino
-
experimental part
p. 4411 - 4418
(2009/12/07)
-
- Method for the production of high-level soluble human recombinant interferon alpha in e. coli and vectors useful for such a production
-
Method for the production of high-level soluble human recombinant interferon alpha protein (rhuIFNα) in E. coli and vectors useful for such a production. Said method comprises the steps of: (1) Transforming an E. coli selected in the group consisting of E. coli protease deficient host strains, and E. coli reductase deficient host strains, with a recombinant expression vector comprising the sequence encoding the glutathione-S-transferase (GST), a junction sequence including a recognition site for a specific protease and a sequence able to encode an interferon alpha (IFN alpha) protein under the control of an inducible promoter, said vector encoding a GST-IFN alpha fusion protein (2) Expressing said interferon alpha protein in conditions comprising the induction of the expression with 0.1 mM-0.5 mM IPTG and a growth temperature of 25° and/or 37°C, depending on said E. coli strain and (3) Isolating the expressed IFN alpha protein.
- -
-
-
- Growth Hormone Secretagogue Receptor 1A Ligands
-
The present invention relates to new growth hormone secretagogue receptor 1A (GHS-R 1A) ligands, and pharmaceutical compositions comprising any of the new GHS-R1 A ligands. The ligands are suitable for a wide range of applications, and thus the present invention also relates to use of the GHS-R1 A ligands according to the present invention in the manufacture of a medicament for the treatment of an individual in need thereof. In another aspect, the present invention relates to a method of treatment of an individual in need thereof, comprising administering to said individual one or more of the GHS-R1A ligands disclosed herein, such as e.g. for treatment of cancer cachexia.
- -
-
-
- Cyclic depsipeptides, ichthyopeptins A and B, from Microcystis ichthyoblabe
-
Bioassay-guided isolation of antiviral compounds from the cultured cyanobacterium Microcystis ichthyoblabe provided two novel cyclic depsipeptides, ichthyopeptins A (1) and B (2). Their structures were determined by 1D ( 1H and 13C) and 2D (COSY, TOCSY, ROESY, HMQC, and HMBC) NMR spectra, ESIMS-MS, and amino acid analysis. The fraction containing both cyclic depsipeptides exhibited antiviral activity against influenza A virus with an IC50 value of 12.5 μg/mL.
- Zainuddin, Elmi N.,Mentel, Renate,Wray, Victor,Jansen, Rolf,Nimtz, Manfred,Lalk, Michael,Mundt, Sabine
-
p. 1084 - 1088
(2008/02/13)
-
- Compositions, kits, and methods relating to the human FEZ1 gene, a novel tumor suppressor gene
-
The invention relates to isolated polynucleotides homologous with a portion of one strand of the human tumor suppressor gene, FEZ1, and to the tumor suppressor protein encoded thereby, Fez1. The polynucleotides are useful, for example, as probes, primers, portions of expression vectors, and the like. The invention also includes diagnostic, therapeutic, cell proliferation enhancement, and screening methods which involve these polynucleotides and protein. The invention further includes kits useful for performing the methods of the invention.
- -
-
-
- Preparation of D-amino acids by enzymatic kinetic resolution using a mutant of penicillin-G acylase from E. coli
-
We have demonstrated for the first time that d-glutamine (d-Gln) and d-glutamic acid (d-Glu) can be efficiently obtained in high ee (97% and 90%, respectively) by enzymatic kinetic resolution of d,l-Gln and d,l-Glu. This was achieved by enantioselective conversion of the l-enantiomers to their N-phenylacetyl derivatives in aqueous solution, using a mutant of penicillin-G acylase (PGA) from E. coli and phenylacetic acid methylester as the acyl donor. Kinetic modeling studies suggest that the high ee values obtained are both due to a strong enantiopreference for the l-amino acid in the deacylation step of the covalent enzyme intermediate, as well as to completeness of conversion that is transiently obtained as a result of the distinct preference of the mutant PGA for phenylacetic acid methylester over the N-phenylacetyl-l-amino acid product. For the other amino acids tested (Asn, Asp, and Ser), the highest ee values that were obtained for the remaining d-enantiomer are moderate (50-80%) because of lower enantioselectivity in the enzyme deacylation step and due to less complete conversion of the l-amino acid caused by competition for the active site between the acyl donor and the N-phenylacetyl-l-amino acid that is produced. The results demonstrate that the mutated PGA has great potential for the production of optically active D-amino acids by kinetic resolution.
- Carboni, Chiara,Kierkels, Hans G. T.,Gardossi, Lucia,Tamiola, Kamil,Janssen, Dick B.,Quaedflieg, Peter J. L. M.
-
p. 245 - 251
(2007/10/03)
-
- Cancer-linked gene as target for chemotherapy
-
Cancer-linked gene sequences, and derived amino acid sequences, are disclosed along with processes for assaying potential antitumor agents based on their modulation of the expression of these cancer-linked genes. Also disclosed are antibodies that react with the disclosed polypeptides and methods of using the antibodies to treat cancerous conditions, such as by using the antibody to target cancerous cells in vivo for purposes of delivering therapeutic agents thereto. Also described are methods of diagnosing using the gene sequences.
- -
-
-
- Epad, an oocyte specific protein
-
The present invention is directed to a human egg specific protein (ePAD), antibodies specific for the human egg specific protein and the use of the ePAD protein to identify antagonists of ePAD activity. Antagonists of ePAD activity are anticipated to have utility as female contraceptive agents.
- -
-
-
- Chicken growth hormone releasing hormone receptor
-
The present invention relates to chicken growth hormone releasing hormone (GHRH), its corresponding receptor, and nucleic acid sequences encoding these proteins. More particularly the present invention is directed to the use of the chicken GHRH hormone and its corresponding GHRH receptor to enhance the production of larger, leaner chickens and other avian species used for meat production.
- -
-
-
- CIS-ELEMENT REGULATING TRANSCRIPTION, TRANSCRIPTIONAL REGULATORY FACTOR BINDING SPECIFICALLY THERETO AND USE OF THE SAME
-
The present invention provides a novel fructose responsive transcription control cis-element and a transcriptional regulatory factor that interacts therewith, a non-human animal having them transferred or inactivated, a diagnostic method for genetic susceptibility to a metabolic disorder using them, and a screening method for a prophylactic or therapeutic drug for a metabolic disorder using them.
- -
-
-
- Small peptides having apoptotic activities and their applications
-
The present invention relates to nine residue peptides (M32-40) from flavivirus M ectodomain able to modulate specifically the apoptotic activity of diverse flavivirus, to pharmaceutical composition comprising the same and their use for the treatment and/or the prevention of flavivirus-linked infections and cancers.
- -
-
-
- Novel protein and use thereof
-
A novel gene likely inhibiting the onset and progress of cancer. A protein having an amino acid sequence which is the same or substantially the same as the amino acid sequence represented by SEQ ID NO:4 or its salt; a polynucleotide encoding the same; and medicinal use, etc. thereof are provided.
- -
-
-
- Interleukin-2:remodeling and glycoconjugation of interleukin-2
-
The invention includes methods and compositions for remodeling a peptide molecule, including the addition or deletion of one or more glycosyl groups to a peptide, and/or the addition of a modifying group to a peptide.
- -
-
-
- Process for producing alpha 2,3/ alpha 2,8-sialyltransferase and sialic acid-containing complex sugar
-
The present invention can provide a process for producing a protein having α2,3/α2,8-sialyltransferase activity using a transformant comprising a DNA encoding a protein having α2,3/α2,8-sialyltransferase activity derived from a microorganism belonging to the genus Pasteurella and a process for producing a sialic acid-containing complex carbohydrate using a transformant capable of producing a protein having α2,3/α2,8-sialyltransferase activity derived from a microorganism.
- -
-
-
- Novel enoyl reductases and methods of use thereof
-
The present provides structurally related enzymes that act as enoyl reductases. These enoyl reductases share a common amino acid consensus sequence, and bind a flavin cofactor. One particular enoyl reductase provided, FabK, catalyzes the identical reaction as the NADH-dependent enoyl-ACP reductase, FabI. Nucleic acids encoding the enoyl reductases, the enoyl reductases, and anitbodies for the enoyl reductases are also included. Methods are also provides for identifying agents that can act to prevent and/or treat bacterial infections.
- -
-
-
- Cancer-linked gene as target for chemotherapy
-
Cancer-linked gene sequences, and derived amino acid sequences, are disclosed along with processes for assaying potential antitumor agents based on their modulation of the expression of these cancer-linked genes. Also disclosed are antibodies that react with the disclosed polypeptides and methods of using the antibodies to treat cancerous conditions, such as by using the antibody to target cancerous cells in vivo for purposes of delivering therapeutic agents thereto. Also described are methods of diagnosing using the gene sequences.
- -
-
-
- Method for evaluating and affecting male fertility
-
A 22 kD sperm protein, SP22, correlates with fertility and predicts fertility in males. The protein can be assayed to detect decreases in fertility resulting from exposure to toxicants and pollutants which are known or suspected to decrease fertility. In an antibody is generated to this protein, the antibody recognition by sperm in an epididymal sperm sample or ejaculate would reflect the fertility of the sample. This antibody can be used as a contraceptive to inactivate sperm, screen for toxicity, select animals for artificial insemination, and select men for assisted reproductive technologies. The protein itself can be inactivated by gene knockout, which is another approach to contraception, or the protein can be added to sperm from infertile men to make fertility techniques more feasible.
- -
-
-
- Assays for screening compounds which interact with cation channel proteins, mutant prokaryotic cation channel proteins, and uses thereof
-
Assays for screeing potential drugs or agents that can interact and potentially bind to cation channel proteins, and potentially have uses in treating conditions related to the function of cation channel proteins is provided, along with prokaryotic cation channel proteins mutated to mimic eukaryotic cation channels, which can then be used in assays of the present invention.
- -
-
-
- Enzymes derived from thermophilic organisms that function as a chromosomal replicase, preparation and use thereof
-
The present invention relates to an isolated DNA molecule from a thermophilic bacterium which encodes a DNA polymerase III-type enzyme subunit. Also encompassed by the present invention are host cells and expression system including the heterologous DNA molecule of the present invention, as well as isolated replication enzyme subunits encoded by such DNA molecules. Also disclosed is a method of producing a recombinant thermostable DNA polymerase III-type enzyme, or subunit thereof, from a thermophilic bacterium, which is carried out by transforming a host cell with at least one heterologous DNA molecule of the present invention under conditions suitable for expression of the DNA polymerase III-type enzyme, or subunit thereof, and then isolating the DNA polymerase III-type enzyme, or subunit thereof.
- -
-
-
- ENZYME FOR CLEAVAGE OF THE ANCHOR REGION OF SURFACE PROTEINS FROM GRAM POSITIVE BACTERIA
-
The invention relates to an enzyme which cleaves surface proteins of gram-positive bacteria, to methods of detecting the enzyme, and methods of isolating the enzyme. In particular, the enzyme is isolated from a group A Streptococcus, and cleaves at the sequence LPXTGX (SEQ ID NO:1). A method for screening putative inhibitors of the enzyme which cleaves the anchor region of surface proteins from gram positive bacteria is also disclosed.
- -
-
-
- Phosphopeptide antigens associated with MHC molecules
-
The present invention describes novel tumor-specific phosphorylated peptides, nucleic acids encoding those peptides, and antibodies generated against said peptides. The genes, peptides, and antibodies described herein may be used as diagnostic indicators of the presence of cancer and/or used in therapeutics to treat cancer.
- -
-
-
- Peptides of IL-2 and derivatives thereof
-
The present invention relates to new peptides of IL-2, and derivatives thereof and their use as therapeutic agents.
- -
-
-
- EGF receptor epitope peptides and uses thereof
-
The present invention relates generally to growth factor receptor epitope peptides, particularly EGF family receptor epitope peptides. The invention also relates to the use of the receptor peptides in generating antibodies which have anti-tumor or anti-cancer activity or in stimulating an immunological response. The invention further relates to antibodies specifically directed against the receptor peptides. Methods for generating an immune response and for treatment of tumors and cancer are also provided.
- -
-
-
- Multi-functional chimeric hematopoietic receptor agonists
-
Disclosed are novel multi-functional chimeric hematopoietic receptor agonist proteins, DNAs which encode the multi-functional chimeric hematopoietic receptor agonist proteins, methods of making the multi-functional chimeric hematopoietic receptor agonist proetiens and methods of using the multi-functional chimeric hematopoietic receptor agonist proteins.
- -
-
-
- Resolution of DL-racemic mixtures
-
The present invention relates to a process for the resolution of DL-racemic mixtures of compounds which crystalize in the form of a conglumerate. Both, the D and L-enantiomers are obtained according to the invention in a industrially feasable process by adding chiral enantioselective polymers to the supersaturated solution of the racemat to inhibit crystalization of one enantiomer. Next a DL-racemic mixture of said compound is suspended in about twice the amount of the crystallized enantiomer. Consequently, the opposite enantiomer could be recovered by said suspension by physical separation.
- -
-
Page column 7-8
(2008/06/13)
-
- Kinetic mechanism of asparagine synthetase from Vibrio cholerae
-
Asparagine synthetase B (AsnB) catalyzes the formation of asparagine in an ATP-dependent reaction using glutamine or ammonia as a nitrogen source. To obtain a better understanding of the catalytic mechanism of this enzyme, we report the cloning, expression, and kinetic analysis of the glutamine- and ammonia-dependent activities of AsnB from Vibrio cholerae. Initial velocity, product inhibition, and dead-end inhibition studies were utilized in the construction of a model for the kinetic mechanism of the ammonia- and glutamine-dependent activities. The reaction sequence begins with the ordered addition of ATP and aspartate. Pyrophosphate is released, followed by the addition of ammonia and the release of asparagine and AMP. Glutamine is simultaneously hydrolyzed at a second site and the ammonia intermediate diffuses through an interdomain protein tunnel from the site of production to the site of utilization. The data were also consistent with the dead-end binding of asparagine to the glutamine binding site and PPi with free enzyme. The rate of hydrolysis of glutamine is largely independent of the activation of aspartate and thus the reaction rates at the two active sites are essentially uncoupled from one another.
- Fresquet, Vicente,Thoden, James B.,Holden, Hazel M.,Raushel, Frank M.
-
-